Orr v. United States ( 2023 )


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  •         In the United States Court of Federal Claims
    No. 18-1894L
    Filed: May 2, 2023
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    ELIZABETH ORR, et al.,                        *
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    Plaintiffs,                 *
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    v.
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    UNITED STATES,                                *
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    Defendant.                  *
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    Brian K. Matise, Burg Simpson Eldredge Hersh & Jardine, P.C., Englewood, CO
    for plaintiffs. With him were Nelson Boyle and Emily Lubarsky Quinn, Burg Simpson
    Eldredge Hersh & Jardine, P.C., Englewood, CO.
    Brian R. Herman, Trial Attorney, Environment and Natural Resources Division,
    Natural Resources Section, United States Department of Justice, Washington, DC, for
    defendant. With him were Zachary T. West, and Frank J. Singer, Trial Attorneys,
    Environment and Natural Resources Division, Natural Resources Section, Jean E.
    Williams, Deputy Assistant Attorney General, Environment & Natural Resources
    Division, Natural Resources Section; and Todd S. Kim, Assistant Attorney General,
    Environment & Natural Resources Division. Bryan Wilson, Attorney-Advisor, Office of
    the Field Solicitor, United States Department of the Interior, Billings, MT, of counsel.
    OPINION
    HORN, J.
    Plaintiffs Elizabeth Orr, Howard Carman, and Lena Carman timely filed a complaint
    in which they assert “claims for taking of their real and personal property entitling them to
    just compensation under the Fifth Amendment to the United States Constitution” against
    the United States. During the month of September 2013, all plaintiffs were owners of real
    property in Larimer County, Colorado, on the Big Thompson River and within the Big
    Thompson River Canyon. Plaintiffs’ properties were located downstream of Olympus
    Dam, which is in Estes Park, Colorado and which is operated by the East Colorado Area
    Office of the United States Bureau of Reclamation, an agency of the United States
    Department of the Interior. Olympus Dam impounds Lake Estes and, as part of the Bureau
    of Reclamation’s Colorado-Big Thompson River (C-BT) Project, Olympus Dam releases
    water from Lake Estes downstream into the Big Thompson River through five radial gates
    located on a spillway.
    Between approximately September 9 and September 16, 2013, area around Estes
    Park, Colorado experienced heavy rainfall and consequential flooding. Plaintiffs allege
    that the Bureau of Reclamation’s operation of Olympus Dam during the September 2013
    storm resulted in the plaintiffs losing “substantially all of their homes, the business owned
    by the Carmans, and their personal property,” as well as “large sections of the land and
    riverfront property owned by Plaintiffs,” which was “displaced or permanently removed
    when it was washed away in the floodwaters released by the Bureau of Reclamation.”
    Plaintiffs’ complaint alleges that “Defendant, through its agents and employees at
    the Bureau of Reclamation, made a conscious decision to release water from the
    Olympus Dam in such quantity as to create a probability, if not a certainty, that Plaintiffs’
    real property, homes, business, and personal property would be destroyed.” Plaintiffs
    further state in their complaint that defendant’s decision to increase releases from
    Olympus Dam was “due to its concern for the integrity of the dam and the greater public
    good in preserving the dam and preventing the possible loss of lives if the dam broke
    versus Plaintiffs’ property.” Moreover, plaintiffs argue that damage to plaintiffs’ property
    “would not have occurred but for the Defendant’s actions,” and that the damage was the
    “foreseeable result of the Defendant’s actions, including the Defendant’s intentional
    discharge of water from the dam.” Plaintiffs claim entitlement to “the fair market value of
    their property that was taken, the fair value of the time they were dispossessed from their
    property, the actual cost to repair and replace the property that can be repaired and
    replaced; the fair lost market value in their properties due to the flooding,” as well as “pre
    and post-judgment interest as allowed by law,” plaintiffs’ “reasonable costs, litigation
    expenses, and attorney and witness fees,” “all other damages and compensation to which
    they [plaintiffs] are legally entitled,” and “such other and further relief as equity and justice
    may allow or require.” (alterations added). Plaintiffs’ complaint asserts one cause of
    action, “Inverse Condemnation,” in which plaintiffs include the claims of Ms. Orr, Mr.
    Carman, and Mrs. Carman. (capitalization and emphasis in original).
    In response to plaintiffs’ complaint, defendant filed a motion to dismiss plaintiffs’
    complaint pursuant to Rule 12(b)(6) (2018) of the Rules of the Court of Federal Claims.
    After briefing, the court denied defendant’s motion to dismiss on the ground that
    “discovery is necessary to determine whether plaintiffs’ allegations demonstrate a taking,
    and, therefore, plaintiffs should be given the opportunity to develop facts in support of
    their claims.” Orr v. United States, 
    145 Fed. Cl. 140
    , 158 (2019). Following the denial of
    defendant’s motion to dismiss, the parties conducted extensive discovery proceedings.
    After the close of discovery, the court held a trial lasting nine days. After reviewing the
    exhibits entered into the record and the testimony offered by the witnesses at trial, among
    whom were the three plaintiffs, the court makes the following findings of fact.
    2
    FINDINGS OF FACT
    Olympus Dam and Lake Estes, which Olympus Dam impounds,1 are located on
    the Big Thompson River in Estes Park, Colorado. The United States Bureau of
    Reclamation owns and operates Olympus Dam as part of the Bureau of Reclamation’s
    C-BT Project, which the parties stipulated “is a water diversion and storage project that
    brings water from the west slope of the continental divide to the east slope, for agricultural,
    municipal, industrial, and hydroelectric generation purposes.” The parties further
    stipulated that the C-BT Project serves, without limitation, two purposes: “(1) transferring
    water from Colorado’s Western Slope to its Eastern Slope for use by the Northern
    Colorado Water Conservancy District (‘NCWCD’) [Northern Water]; and (2) the
    generation of electricity marketed by the Western Area Power Administration (‘WAPA’).”2
    (alteration added).
    According to a Senate Report, dated June 15, 1937, titled “Synopsis of Report on
    Colorado-Big Thompson Project, Plan of Development and Cost Estimate Prepared by
    the Bureau of Reclamation, Department of the Interior,” (capitalization in original), the C-
    BT Project has five purposes:
    1. To preserve the vest and future rights in irrigation.
    2. To preserve the fishing and recreational facilities and the scenic
    attractions of Grand Lake, the Colorado River, and the Rocky Mountain
    National Park.
    3. To preserve the present surface elevations of the water in Grand Lake
    and to prevent a variation in these elevations greater than their normal
    fluctuation.
    4. To so conserve and make use of these waters for irrigation, power,
    industrial development, and other purposes, as to create the greatest
    benefits.
    5. To maintain conditions of river flow for the benefit of domestic and
    sanitary uses of this water.
    The record before the court includes the Standard Operating Procedures of
    Olympus Dam, Estes Powerplant, and Lake Estes, dated April 2005, which were in effect
    at the time of the September 2013 storm. The Standard Operating Procedures provide,
    under the heading “PURPOSE OF THE PROJECT,” in relevant part: “The primary
    purpose of the Project is to provide supplementary water to 720,000 acres of irrigated
    1 Witnesses at trial consistently testified that Olympus Dam “impounds” the Lake Estes
    reservoir, and the parties also use that term in their briefs.
    2 Tim Miller, a hydrologist for the Bureau of Reclamation, described in his testimony that
    the WAPA is a hydropower wholesaler which markets to customers the power generated
    by the Bureau’s C-BT facilities.
    3
    land in northeast Colorado. The secondary purpose is to utilize the power potential of the
    water as it drops 2,800 feet between the Alva B. Adams Tunnel and the foothills storage
    system.” (capitalization and emphasis in original).
    Upstream of Olympus Dam in the C-BT Project is the Adams Tunnel, which the
    parties stipulated “brings water from the C-BT’s west slope facilities” through the
    mountains of the continental divide “to the east slope, depositing water in the East Portal
    Reservoir.” The maximum flow of Adams Tunnel is 550 cubic feet per second (cfs).3
    According to the testimony of Carlos Lora, a hydrologic engineer and water scheduler in
    the Water Resources Group of the East Colorado Area Office of the Bureau of
    Reclamation, United States Department of the Interior, the flow of Adams Tunnel is
    measured at the East Portal Reservoir. According to the testimony of James VanShaar,
    who was the head of the Water Resources Group in the East Colorado Area Office of the
    Bureau of Reclamation, United States Department of the Interior, during the September
    2013 storm, once the water from Adams Tunnel is deposited in the East Portal Reservoir,
    “[a]lmost all of it goes into the Marys Lake Powerplant,” which has a capacity of
    approximately eight megawatts. (alteration added). From Marys Lake Powerplant, water
    passes into Marys Lake and through the Estes Powerplant. Estes Powerplant has a
    capacity of 45 megawatts, divided between three 15-megawatt units. The water leaving
    Estes Powerplant then flows into Lake Estes alongside the Big Thompson River.
    Olympus Dam impounds Lake Estes. The parties stipulated that water comes into
    the Lake Estes reservoir through “the Estes Power Plant, the Big Thompson River above
    Lake Estes, Fish Creek, other smaller creeks and natural inflows, and rainfall over the
    reservoir.” The parties further stipulated that water leaves the Lake Estes reservoir “(1)
    through one or more of the five spillway gates into the Big Thompson River; (2) through
    a small slide gate into the Big Thompson River; and (3) through the Olympus Tunnel.”
    Water that leaves Lake Estes through the spillway gates or the slide gate of Olympus
    Dam enters the Big Thompson River, in the Big Thompson River Canyon, “below” or
    downstream from Olympus Dam. Water that leaves Lake Estes through the Olympus
    Tunnel enters another portion of the C-BT Project but, as the parties stipulated, may “re-
    enter the Big Thompson River near the mouth of the Big Thompson River Canyon,”
    downstream of plaintiffs’ properties. According to the parties’ stipulations, “[i]n most
    normal operating circumstances, and absent appropriate state authorization, natural
    runoff into the C-BT is not project water” belonging to the Bureau of Reclamation, and,
    therefore, “the majority of water in Lake Estes is C-BT water.” (alteration added).
    According to the parties’ joint stipulations, water that passes through Olympus
    Dam flows into the Big Thompson River, and joins a tributary downstream, the North Fork
    Big Thompson River at the confluence at Drake, Colorado, within the Big Thompson River
    Canyon. According to the testimony of James VanShaar and a diagram of the C-BT
    Project admitted as a joint exhibit at trial, when the Big Thompson River reaches the
    mouth of the Big Thompson River Canyon, a portion of the water passes through the City
    of Loveland Powerplant, also identified as the Idylwilde Powerplant, before rejoining the
    3 Two abbreviations of “cubic feet per second” appear throughout this Opinion, “cfs” and
    “ft3/s.” The abbreviations “ft3/s” or “ft3” (cubic feet) appear only in quotations.
    4
    Big Thompson River immediately thereafter. Downstream of the Idylwilde Powerplant, a
    portion of the water in the Big Thompson River is diverted through the Big Thompson
    Tunnel and the Dille Diversion Dam to flow through the Big Thompson Powerplant, while
    the majority of the water continues to flow in the Big Thompson River. Mr. VanShaar
    testified that the Big Thompson River is typically “a very small river, barely more than
    what they would call a creek in other parts of the country,” with an average flow of between
    50 and 75 cfs, and shallow enough that, in most places, “you could walk across it.”
    According to the testimony of Anthony Curtis, chief of the Resource Division at the
    East Colorado Area Office of the Bureau of Reclamation, United States Department of
    the Interior, the majority of the water in facilities in the Eastern Slope portion of the C-BT
    comes from the Western Slope via the Adams Tunnel, and rights to most of that water
    are held by Northern Water. In the Eastern Slope facilities of the C-BT Project, water
    travels downstream in the direction of what Mr. Curtis described as the “terminus
    reservoirs” of Carter Lake and Horsetooth Reservoir, from which reservoirs it is delivered
    to the constituents of the project.
    Water that leaves Lake Estes through the Olympus Tunnel typically travels through
    the Bureau of Reclamation’s Pole Hill Powerplant. The Pole Hill Powerplant has a
    capacity of 35 megawatts. In the event that the Pole Hill Powerplant is taken offline, the
    Bureau can redivert water though a Rediversion Structure in Little Hells Canyon,
    Colorado. According to the testimony of Mr. VanShaar, water that is rediverted through
    Little Hells Canyon enters the North Fork of the Little Thompson River and then the
    Rattlesnake Canal and Tunnel. Mr. VanShaar also testified that “some small amount less
    than 550 cfs can be rediverted at the rediversion structure.” According to the testimony of
    Ralph Beall, facility manager of the C-BT Project at the Bureau of Reclamation, United
    States Department of the Interior, the Rediversion Structure is “made out of timbers,
    perhaps six-inch by six-inch, and they [the water] go through some gates that go into the
    afterbay of Pole Hill.” (alteration added). Water which is not rediverted away from the Pole
    Hill Powerplant travels through the Pole Hill Powerplant and into the Pole Hill afterbay,
    which, according to the testimony of Mr. Beall, “has a very small levee, to push that water
    through the siphon into Pinewood Reservoir.” Mr. VanShaar indicated that whether the
    water passes through the Pole Hill Powerplant or is rediverted through Little Hells
    Canyon, however, the water ultimately flows into the Pinewood Reservoir and the Flatiron
    Powerplant. The Flatiron Powerplant has three generators, two with 45-megawatt
    capacities, and one with a ten-megawatt capacity. Some of the water which passes
    through the Flatiron Powerplant is diverted to Carter Lake, one of the C-BT’s two terminal
    reservoirs, while the remainder of the water continues flowing into the Charles Hansen
    Feeder Canal. The Charles Hansen Feeder Canal carries water to the Big Thompson
    Powerplant at the mouth of the Big Thompson River Canyon or to the Horsetooth
    Reservoir, according to the testimony of Mr. Beall and Mr. VanShaar.
    According to Mr. VanShaar, most of the water in the C-BT Project ultimately
    passes through a three-flow system known as the Trifurcation at the mouth of the Big
    Thompson River Canyon. The water which re-enters the Big Thompson River continues
    flowing south as far as Boulder, Colorado. The Trifurcation was described by Mr. Beall as
    “different ways that we [the Bureau] can move water through Big Thompson Powerplant”
    5
    after passing through the rest of the upstream C-BT system. (alteration added). First, Mr.
    Beall testified, water which is not sent through the Olympus Tunnel, but stays in the Big
    Thompson River is skimmed4 “at a diversion called Dille Tunnel, which is at the Narrows
    a couple miles upstream of the power plant,” and from there the water flows into the 930
    Section of the Charles Hansen Feeder Canal and on to the Big Thompson Powerplant.
    Second, according to Mr. Beall, water may pass through the Olympus Tunnel and the
    Pole Hill Powerplant, Pinewood Reservoir and Flatiron Powerplant, Carter Lake and then
    into the 930 Section of the Charles Hansen Feeder Canal, which leads to the Big
    Thompson Powerplant. Third, water in the 930 Section, rather than flowing into the Big
    Thompson Powerplant, can instead flow north into another section of the Charles Hansen
    Feeder Canal, the 550 Section, and from there flow into Horsetooth Reservoir, according
    to Mr. Beall’s testimony.
    The parties stipulated that Olympus Dam is composed of “an earthen embankment
    portion [of the dam], with crest elevation 7,481 feet above sea level, and a concrete gravity
    dam featuring a spillway.” (alteration added). Through five release gates in the concrete
    gravity dam, also referred to interchangeably as “radial gates” and “spillway gates,” the
    Bureau of Reclamation can release water from Lake Estes into the Big Thompson River.
    Mr. VanShaar testified that the spillway release gates raise vertically to release water
    onto the spillway. The parties stipulated that when closed, “[t]he top of the spillway gates
    is elevation 7,475 feet above sea level.” (alteration added). At trial, Adam Northrup, an
    engineering technician with the Bureau of Reclamation, United States Department of the
    Interior, testified regarding the operation of the spillway gates, “there’s a cable that’s
    connected to the bottom of the radial gates,” which is connected to mechanisms, called
    trunnions, on the outside, or downstream side, of the gates, “and the trunnions are the
    hinge, and the cable pulls up from the bottom of the gate and there’s a motor on the cable
    to reel it in,” and by reeling the cable in, the mechanism opens the gate.
    The parties stipulated that the spillway of Olympus Dam has a “design capacity” of
    21,200 cfs. Of the five spillway release gates, the Bureau of Reclamation office at Casper
    Control Center in Wyoming can operate one gate remotely, “up to a maximum release of
    approximately 900cfs.” According to the testimony of Mr. Beall, Gate 3, the middle gate,
    is the release gate which is typically operated remotely. According to the parties’ joint
    stipulations and the Post Incident Analysis Report on the September 2013 flood prepared
    by the Bureau of Reclamation (the Post Incident Analysis Report),5 a dam operator must
    be present at the dam in order to open the remotely operated gate further than a release
    of 900 cfs, or to open any of the four gates which are not remotely operated.
    Olympus Dam is classified by the Bureau of Reclamation as a “high hazard dam,”
    which the parties stipulated that the Bureau of Reclamation defines “as one in which more
    than six lives would be in jeopardy and excessive economic loss would occur as a direct
    4 At trial, Mr. Miller testified that “skimming” water means to borrow water from the river
    for use in generating hydropower and returning the water to the river within 24 hours.
    5The Post Incident Analysis Report on the September 2013 flood was jointly submitted
    by the parties as an exhibit and is dated October 2014.
    6
    result of dam failure.” According to the testimony of Mr. Northrup, in the event that the
    water in Lake Estes overtopped Olympus Dam, water would overtop the spillway gates
    first, which are lower than the earthen portion. According to the testimony of Mr. Beall,
    Olympus Dam is “an important link in the [C-BT] system.” (alteration added). Olympus
    Dam’s importance is due in large part to the fact that, absent Olympus Dam, the Bureau
    of Reclamation could not divert water through the Olympus Tunnel towards the Pole Hill
    and Flatiron powerplants. Mr. Beall explained that Olympus Dam is also necessary to the
    functioning of the facilities down the Olympus Tunnel because Olympus Dam, by
    impounding Lake Estes, creates the “head,” or difference in water elevation, necessary
    to drive water through the Olympus Tunnel and into the Pole Hill Powerplant and other
    downstream powerplants on that branch of the C-BT Project.
    The Standard Operating Procedures for Olympus Dam describe the dam as
    follows:
    The dam is a 1,951-foot-long composite structure, consisting of a zoned
    earth embankment with slopes of 3:1 H:V[6] upstream and 2:1 H:V
    downstream, and a concrete gravity dam containing a spillway overflow
    section. The upstream face of the earth embankment is protected by a layer
    of riprap and the downstream face is protected by a layer of rock and cobble
    fill.
    (footnote added). Further, according to the Standard Operating Procedures:
    The maximum structural height of the concrete gravity dam is 70 feet, at the
    contact with the earth embankment. The structural height of the
    embankment section is 70 feet with a crest width of 30 feet. The concrete
    portion of the dam has a crest width of 10.5 feet including the overhang of
    the parapet and curb, and a maximum base width of approximately 60 feet,
    not including the spillway apron. Construction of Olympus Dam was
    completed in 1949.
    The parties stipulated that “Olympus Dam is not a flood control dam,” meaning that the
    Lake Estes reservoir has a relatively small capacity: in the “operational range” of the
    reservoir, between 7,469.57 feet elevation and 7,474 feet elevation, “Lake Estes can store
    740 acre-feet of water,” and the entire capacity of Lake Estes up to 7,474 feet elevation
    6Neither the Standard Operating Procedures nor the witnesses at trial defined “H:V” as
    used in the Standard Operating Procedures.
    7 While 7,469.5 feet in elevation is referred to as the bottom of the operational pool,
    according to the Standard Operating Procedures, “[n]ormally, the reservoir is maintained
    between elevations 7471 and 7475 for recreation,” which according to the testimony of
    Mr. VanShaar refers to the water level necessary for activities like boating and fishing.
    (alteration added).
    7
    is 3,069 acre-feet.8 With respect to the storage capacity of the reservoir, the Standard
    Operating Procedures for Olympus Dam refer to the elevation range between 7,450.25
    feet and 7,475 feet as “Active Conservation Storage,” while the elevation range between
    7,474 feet and 7,475 feet is labeled “Regulatory Reserve,” which the Standard Operating
    Procedures explain as “a sub pool within the active conservation storage containing water
    immediately below the spillway but above the normal water surface used for power
    generation, which should be used only in emergency situations.” Paula O’Brien, who at
    the time of the September 2013 flood was known as Paula Baty and who worked as a
    dam safety engineer at the East Colorado Area Office of the Bureau of Reclamation,
    United States Department of the Interior, testified that “there are a number of implications”
    to the fact that Olympus Dam is not a flood control dam, “the most important” of those
    implications being that “neither its outlets nor its size is designed to manage flood flows.”
    The Standard Operating Procedures for Olympus Dam require the keeping of an
    Operating Log, and state, under the heading “CERTIFICATION OF STANDING
    OPERATING PROCEDURES REVIEW BY OPERATING PERSONNEL:” “All operating
    personnel will certify the above and sign the Operating Log.” (capitalization and emphasis
    in original). The Standard Operating Procedures further state, under the heading “G.
    OPERATING LOG:”
    The purpose of the Operating Log is to have a chronological record of all
    important events to provide a continuing record of operating activities, and
    to provide clues to the possible cause of equipment trouble or the
    development of unusual conditions occurring at the dam.
    The Operating Log shall be kept in the control house in a bound book. A
    sample of an Operating Log (Form 7-1623) is shown in appendix B-2. All
    entries shall be in ink or other indelible material. Corrections in the logbook
    shall be made by crossing out the incorrect notation so that it is still legible,
    and adding the correct entry. Do not erase or eradicate entries in the
    logbook.
    A logged record shall be maintained by the operating personnel or
    designated alternate on duty. Portions of the information will be available
    from automatic recordings and monitoring equipment. Specific data may
    vary in form and content to fit the needs and conditions present at the dam.
    In general, the data shall include information such as:
    •   Normal and emergency changes in operation of outlet works and/or
    spillways including individual gate changes and positions.
    •   Water elevations and discharges.
    •   Startup and stopping of mechanical equipment.
    •   Testing of standby equipment or gate controls.
    8The elevation of 7,474 feet also was referred to by Mr. Lora as the top of the “operational
    pool” and by Mr. VanShaar as the top of the “regulatory pool.”
    8
    •   Minor and major maintenance activities including scheduled
    maintenance.
    •   Reservoir surveillance.
    •   Initial acknowledgement of unusual or emergency conditions.
    •   Requests and concurrence to change from normal operation during
    unusual or emergency conditions.
    •   Exercising of all gates and valves.
    •   Communications network checks.
    •   Record of names and address of official visitors and all Reclamation
    review teams.
    •   Reports on acts of vandalism.
    •   Certification of SOP [Standard Operating Procedures] review by
    Dam Operator and supervisor.
    •   Record of Comprehensive/Periodic Facility Review and annual
    examinations.
    •   Certification and type of Dam Operator’s training.
    •   Miscellaneous items pertinent to operation and emergency or
    unusual incidents at the structures.
    •   Record of performance of “Ongoing Visual Inspections.”
    Some other approved record forms are included in Appendix B. These
    records are also considered part of the dam operator’s Operating Log, and
    shall be accessible at all times.
    The Operating Log is kept in the control house at Olympus Dam.
    (capitalization and emphasis in original; alteration added). According to the testimony of
    Mr. VanShaar, the Operating Log for Olympus Dam was kept at Casper Control Center
    in Wyoming by Bureau personnel, and contained entries not only for Olympus Dam, but
    also for Lake Estes and other relevant C-BT Project facilities.
    Moreover, the Bureau of Reclamation’s Standard Operating Procedures, as
    included in the record before the court, provide for an Emergency Action Plan, which is
    dated May 2003 in the version included in the record before the court. The parties
    stipulated that, pursuant to the Standard Operating Procedures and the Emergency
    Action Plan, the Eastern Colorado Area Office designates an Incident Management
    Team9 in emergency situations. According to the parties’ stipulations, the “IMT [Incident
    Management Team] includes employees from various components of the ECAO [East
    Colorado Area Office]” and “is responsible for managing the ECAO’s response to the
    event.” (alterations added). According to the parties’ joint stipulations, “in the beginning
    9 In his testimony at trial, water scheduler Mr. Miller referred to an “Incident Command
    Team,” which was tasked primarily with communication with the media, whereas the
    Incident Management Team was concerned with coordinating “the different emergency
    responders for the different cities and the sheriff’s offices and things like that,” as well as
    declare Response Levels.
    9
    of the September 2013 storm,” the East Colorado Area Office formed an Incident
    Management Team, and Ralph Beall was designated the “Incident Commander” of the
    Incident Management Team. The Post Incident Analysis Report prepared by the Bureau
    of Reclamation explains:
    The Colorado Big Thompson Facility Manager, Ralph Beal [sic], was the
    Incident Commander as delegated by the ECAO [East Colorado Area
    Office] Area Manager, Michael Collins (Agency Administrator). An Incident
    Management Team (IMT) concept was used which helped facilitate better
    span of control, chain of command, resource management, facilitate
    awareness of project operations and maintain situational awareness. ECAO
    had adopted Incident Command Systems (ICS) for incident management
    across its projects and has conducted ICS training and incorporated these
    concepts into their EAPs [Emergency Action Plans].
    The ECAO Incident Commander has the authority to declare an emergency
    at Olympus Dam and activate the IMT. The ECAO ICS organizational
    structure for this event is shown in the figure below.
    (alterations added).
    The Post Incident Analysis Report indicates that, alongside Mr. Beall, the Incident
    Management Team consisted of the Liaison Officer, Jacklynn Gould, the Safety Officer,
    David Hartman, the Security Officer, Howard Bailey, the Agency Representatives to the
    City of Loveland Emergency Operations Center, James VanShaar and Andrew Gillmore,
    and the Public Information Officer, Kara Lamb, although the Post Incident Analysis Report
    does not specify at what times the members joined the Incident Management Team.
    Paula O’Brien, who, as noted above, was at the time serving as safety engineer in the
    East Colorado Area Office, testified at trial that she also joined the Incident Management
    Team sometime the morning of September 12, 2013. The Post Incident Analysis Report
    indicates that the Incident Management Team reported to the Agency Administrators for
    the East Colorado Area Office, identified as the Manager, Michael Collins, and the Deputy
    Manager, Jacklynn Gould, who, as noted above, also served as the Liaison Officer. At
    trial, Mr. Beall testified that, despite holding the title “Incident Commander,” he was not
    the “lead decision-maker,” and Mr. Beall identified three individuals who outranked him:
    Michael Collins and Jacklynn Gould, who Mr. Beall identified as “my boss’ boss and boss,”
    and Charles Pedersen, who Mr. Beall identified as “my direct boss” and who the Post
    Incident Analysis Report identifies as head of the Operations Section. 10 Mr. Beall further
    testified that, when holding the tile of Incident Commander, he remained “the facility
    manager at the same time.” Mr. Beall described the decision-making process for the
    Incident Management Team:
    So the incident command team would meet. Water scheduling is watching
    and monitoring the precipitation event. They come in with data. We
    10At trial, Mr. Northrup identified Mr. Pedersen as the “chief of Operating and
    Maintenance Division” at the time of the September 2013 flood.
    10
    collectively meet as a group, whether it’s by phone or in person. We assess
    the situation and what is occurring right at that moment.
    Then we look at the Emergency Action Plan to see if we need to go to an
    alert level, and then we pass on that information. And in my case, I’d be
    passing on information to my subordinates on infrastructure planning,
    making sure we’re ready for whatever the situation might be, and then
    there’s a contact string where, for instance, the Great Plains duty officer
    needs to be contacted, public information officer may need to outreach to
    people. So that’s kind of how the meeting would go.
    And then we would agree on an alert level and what possible changes could
    make us have to meet again, and agree on responsibilities throughout the
    organization.
    Mr. Beall further explained:
    Then my plan was to pass that information on to my foreman and then
    ultimately on to the staff to be ready to act as needed, and then there is a
    list of contacts that need to be made as you go through your alert levels,
    starting with internal alert, Level 1, Level 2, Level 3, et cetera.
    Our security officer, Howard Bailey, and emergency management man, at
    the very first meeting, he volunteered to make those notifications throughout
    our process and then confirmed with me after he had done that.
    Mr. Beall also testified that “[a]lways when you have a situation, you start with your
    Emergency Action Plan,” which Mr. Beall indicated was Bureau of Reclamation policy.
    (alteration added). While the Post Incident Analysis Report stated that the “Incident
    Commander, has the authority to declare an emergency at Olympus Dam and activate
    the IMT,” (alteration added), Mr. Beall testified that he did not “recall independently having
    the authority to declare an emergency at Olympus Dam,” but rather stated that “we [the
    Incident Management Team] start by meeting, using our collective knowledge and
    experience, and going through our documents and agreeing on what actions we’re going
    to take.” (alteration added). According to the Post Incident Analysis Report prepared by
    the Bureau, which was corroborated by the testimony of Mr. Beall and Mr. Miller, Mr.
    Bailey was responsible for public notifications from the Incident Management Team, as
    follows:
    Official notification of dam Response Levels and project operations
    including operational releases from Olympus dam were made by the ECAO
    Emergency Management Coordinator (Howard Bailey). Public information
    was coordinated directly with the public and the media by the ECAO Public
    Information Officer (PIO) (Kara Lamb). The official notification process was
    followed in accordance with the EAP [Emergency Action Plan] and
    Reclamation policy. The ECAO made Response Level notifications to the
    11
    Great Plains Region Duty Officer (GPRDO) in a timely fashion and provided
    sound information on incident details.
    (alteration added).
    According to Mr. Beall’s testimony, “the Incident Management Team met on a
    regular basis during the [September 2013] storm event.” (alteration added). According to
    the testimony of Mr. Miller, the Incident Management Team functioned mainly to pass on
    information and that the water schedulers, whose function was to make decisions
    regarding releasing water into the river. Ms. O’Brien testified that, in her role in the Incident
    Management Team, she “would relay information and requests about monitoring and
    what we needed to do and critical information about the engineering or structure of the
    facility” to Mr. Beall, and “let him know what resources we would need and when -- when
    we might need to do different things” with the operation of Olympus Dam.
    The Emergency Action Plan for Olympus Dam, as included in the record before
    the court and in effect during the September 2013 storm, provides for five levels of
    emergency response, which range from “Internal Alert,” the least severe response level,
    to Response Level 4, the most severe response level, indicating failure of Olympus Dam.
    In relevant part, the Internal Alert response level is defined by the Emergency Action Plan:
    1. The Internal Alert Response Level is the least serious of the Response
    Levels. Declaration of the Internal Alert Response Level means that an
    “Internal Alert” will be conducted in which emergency response activities
    including internal notifications for affected organizations will be carried out.
    2. This means that these organizations will observe and analyze the event,
    and that they will “stand-by” because nothing “serious” is happening yet. But
    indications are that something definitely IS happening that could develop
    into a potentially significant threatening event only if it intensifies.
    (capitalization and emphasis in original). Response Level 1 is defined in relevant part:
    1. Declaration of Response Level 1 means that involved organizations need
    to “Standby” for additional information relative to developing conditions.
    Nothing significant really needs to be done for Response Level 1 except to
    stay aware of the event after it is detected, and observe and analyze it for
    possible action. Nothing significant has developed yet, but indications are
    that something definitely IS happening that could progress into a potentially
    significant threatening event if it continues or intensifies.
    2. Local emergency management officials of jurisdictions downstream will
    receive, and be encouraged to conduct, a “communications check” during
    Response Level 1 to allow their response organizations to go into alert
    status. Response agencies generally do not mobilize resources for
    declaration of Response Level 1.
    12
    3. Response Level 1 does NOT represent an emergency YET, but may be
    perceived as such by the media or general public. Nor does Response Level
    1 pose a hazard, either at the dam or to downstream populations at risk, at
    the time of observation.
    (capitalization and emphasis in original). The definition of Response Level 1 also
    provides: “Any developing events that belong in Response Level 1 will be identified as
    being of a level of intensity where they can be managed and brought under control by the
    dam operating personnel with NO NEGATIVE IMPACTS DOWNSTREAM.”
    (capitalization in original).
    Response Leve 2 is defined in relevant part:
    1. Declaration of Response Level 2 means that conditions are now more
    serious than those in Response Level 1 but not yet serious enough to
    declare Response Level 3.
    2. For this Response Level, the dam will not have failed, nor is failure
    imminent. However, the condition of the structure will currently be unstable,
    or operational releases will be such that they may become life-threatening.
    This means that the dam may yet be stabilized, or that operational releases
    may not actually impact populations at risk if conditions diminish in intensity
    or are brought under control, but circumstances are such that populations
    at risk MUST BE placed on “stand-by” status which means notifications to
    populations at risk should include directions to BEGIN PREPARATIONS to
    leave predetermined inundation areas for higher ground and safe shelter. It
    also means that conditions COULD worsen that WOULD require an
    evacuation if not brought under control effectively.
    3. Upon notification of declaration of Response Level 2, local emergency
    management officials and response agencies will be encouraged to
    mobilize resources and position them at staging areas. For flood operations,
    initiate road access closures and begin staging evacuation of low areas as
    flood releases are staged up.
    (capitalization in original). The definition of Response Level 2 further provides:
    “Notification to designated downstream 24-hour warning points is a REQUIRED ACTION
    THAT WILL BE TAKEN whenever Response Level 2 is declared.” (capitalization in
    original).
    Response Level 3 is defined in relevant part:
    1. Declaration of Response Level 3 means involved organizations must
    “GO” (initiate evacuation). Declaration and implementation of Response
    Level 3 means the situation is extremely serious. For this Response Level,
    major life-threatening operational releases will be made, major structural
    damage to the dam will occur, or the physical condition of the dam will have
    13
    deteriorated such that stabilization is not possible and the dam will most
    likely fail.
    2. For this Response Level, one, or more, of the following emergency
    conditions will be present:
    a. OPERATIONAL RELEASES HAVE BECOME LIFE-THREATENING.
    b. THE DAM IS IN DANGER OF IMPENDING FAILURE.
    3. Declaration of this Response Level means populations at risk are in
    IMMINENT DANGER and that evacuation of populations at risk in all or a
    portion of the dam failure flood inundation area is REQUIRED!
    (capitalization in original). The definition of Response Level 3 further provides:
    5. Response Level 3 will be declared and initiated for all situations
    ANYTIME that it becomes obvious, through analysis of threatening events,
    that IMMEDIATE EVACUATION of populations at risk located downstream
    from the affected dam is necessary! Again, notification to the downstream
    24-hour Warning Point(s) is a REQUIRED ACTION THAT WILL BE TAKEN
    whenever Response Level 3 is declared.
    6. Declaration of Response Level 3 will be based on the certainty that LIFE-
    THREATENING floodwaters will affect populations at risk.
    7. In cases where Response Level 3 is declared without passing through an
    Internal Alert or Response Levels 1 and/or 2 first, carrying out expected
    actions for Response Level 3 is the first priority. Expected actions for the
    Internal Alert or Response Levels 1 and 2 will be checked and completed
    only after having completed them for Response Level 3 first.
    8. A protective action recommendation will be made that local authorities
    issue an [sic] public evacuation warning to immediately leave flood
    inundation areas for safe areas.
    9. Local authorities are responsible for advising the public on safe
    evacuation routes and where to go for safe shelter. Response organizations
    will be encouraged to fully mobilize and physically implement evacuation
    procedures for Response Level 3.
    (capitalization in original).
    Response Level 4 is defined in relevant part:
    1. Declaration of Response Level 4 means the dam is “GONE” (it has
    failed). This is the most dangerous Response Level.
    14
    2. For this Response Level, the following emergency conditions will be
    present:
    a. THE DAM IS FAILING/THE DAM HAS FAILED.
    b. RESULTANT RELEASES ARE EXTREMELY LIFE-THREATENING.
    3. Declaration of this Response Level means populations at risk and
    response personnel conducting evacuations in inundation areas are in
    IMMINENT DANGER and that they should leave the dam failure flood
    inundation area IMMEDIATELY!
    (capitalization and emphasis in original).
    The Emergency Action Plan provides a set of “Initiating Conditions” for each of the
    emergency response levels. Under the heading “Decision-Making,” the Emergency
    Action Plan provides, in relevant part:
    The decision will be made by the Area Office to declare a specific response
    level based on an analysis of identified initiating conditions for Olympus
    Dam. For hydrologic events, the decision will be made by the Area Office
    based on the April 1996 Olympus Dam Early Warning System Decision
    Criteria Document. The dam operator will only declare a Response Level in
    the event communications between the dam and the Area Office is
    interrupted or the initiating conditions require going immediately to a Level
    3 Response.
    The Emergency Action Plan categorizes initiating conditions for all response levels except
    for Response Level 4 as either “HYDROLOGIC EVENTS,” “EARTHQUAKE,” or “ALL
    OTHER EVENTS.” (capitalization in original).
    The Emergency Action Plan provides the following initiating condition for an
    Internal Alert response level with respect to hydrologic conditions: “It becomes evident,
    based on rainfall and streamflow data being received from the EWS [Early Warning
    System] basin-monitoring equipment, that releases of 1,000 ft 3/s will need to be made
    from the dam.” (alteration added). The Emergency Action Plan provides the following two
    initiating conditions for Response Level 1 with respect to hydrologic conditions:
    a. A Flash Flood Watch, Flood Watch, or Severe Storm Watch is issued
    by the National Weather Service for the Estes Park area or the Olympus
    Dam Drainage Basin.
    b. It becomes evident, based on rainfall and streamflow data being received
    from the EWS basin-monitoring equipment, that releases of 1,100 ft3/s will
    need to be made from the dam. An existing agreement requires
    Reclamation to contact the City of Loveland when a release of 1,100 ft 3/s
    will be made.
    15
    (capitalization and emphasis in original).
    The Emergency Action Plan provides the following four initiating conditions for
    Response Level 2 with respect to hydrologic events:
    a. A Flash Flood Warning, Flood Warning, or Severe Storm Warning is
    issued by the National Weather Service for the Estes Park area or the
    Olympus Dam Drainage Basin.
    b. It becomes evident, based on rainfall and streamflow data being received
    from the EWS basin-monitoring equipment, that releases of 1,500 ft 3/s will
    need to be made from the dam. It is at a flow of 1,500 ft 3/s in the Big
    Thompson River that water level first reaches the level of homes and
    businesses below Olympus Dam.
    c. Rainfall totals greater than 1.2 inches in 1 hour or 1.7 inches in 3 hours
    at half of the operating rain gauges. Refer to the April 1996 Olympus Dam
    EWS Decision Criteria Document.
    d. It becomes evident, based on rainfall and streamflow data being received
    from the EWS basin-monitoring equipment, that inflows to Lake Estes will
    reach 5,000 ft3/s. It is estimated that the Olympus Dam spillway will being
    plugging at inflow of about 5,000 ft3/s.
    (capitalization and emphasis in original).
    The Emergency Action Plan provides the following two initiating conditions for
    Response Level 3 with respect to hydrologic events:
    a. It becomes evident, based on rainfall and streamflow data being received
    from the EWS basin-monitoring equipment, that releases of 1,500 ft 3/s will
    need to be made from the dam. As mentioned earlier, it is at a flow of 1,500
    ft3/s in the Big Thompson River that water level first reaches the level of
    homes and businesses below Olympus Dam. Also, most structures in the
    Big Thompson Canyon Below Olympus Dam are inundated at a flow of
    6,000 ft3/s. Once Response Level 3 has been declared, continual contact
    will need to be established between Reclamation and downstream
    authorities so that evacuation of downstream populations can be
    coordinated with anticipated releases from the Dam.
    b. Rainfall totals greater than 1.5 inches in 1 hour or 2.2 inches in 3 hours
    at half of the operating rain gauges. Refer to the April 1996 Olympus Dam
    EWS Decision.
    (capitalization and emphasis in original). The Emergency Action Plan provides only one
    initiating condition for Response Level 4, without categorization: “Olympus Dam begins
    to fail, or has failed, from any cause.”
    16
    The Emergency Action Plan further provides tables of “EXPECTED ACTIONS” for
    each of the Response Levels. (capitalization and emphasis in original). The Emergency
    Action Plan states, under the heading “EXPECTED ACTIONS TABLES:”
    1. Expected Actions of organizations have been arranged according to the
    severity and time of occurrence of the developing emergency event and
    then placed under the appropriate Response Levels. This means that
    the Expected Actions for each organization will be the response actions
    that organization will implement when that Response Level is declared.
    This operating methodology has been designed to help prevent
    organizations from over or under reacting to the observed and identified
    emergency event that is occurring.
    2. The Expected Actions for each organization under each Response Level
    listed are presented in columnar format with three columns.
    3. Column 1 presents the tasks or responsibilities an agency or individual
    will need to implement in response to declaration of the Response Level.
    In all cases, the responsible person (by title) who is responsible to
    ensure that the listed task and/or responsibility is carried out for each
    office is as follows:
    a. DAM OPERATIONS PERSONNEL: The Dam Operator and/or the
    Facility Supervisor, for the Estes/Marys Lake Powerplant.
    b. LOVELAND CONTROL CENTER (LCC): The LCC Operator and/or
    Foreman.
    c. EASTERN COLORADO AREA OFFICE (ECAO): Water
    Scheduling/Safety of Dams Staff or Division Chief and/or the Area
    Manager.
    d. GREAT PLAINS REGIONAL OFFICE (GPRO): Facility Operation
    Services Group Staff or Group Leader and/or the Infrastructure and
    Engineering Services Group Manager.
    4. Column 2 provides space for personnel to date/time stamp when the
    listed task/responsibility was completed. This, in effect, becomes the
    documentation for final reports that must be submitted upon cessation
    of emergency operations.
    5. Column 3 lists “Location of the Implementing Procedure”. [sic] This
    procedure may be located somewhere in the Emergency Action Plan,
    Standard Operating Procedures, or in some other procedural document
    for the organization.
    6. The four Response levels shown are sequenced in ascending order of
    severity for each individual and/or organization.
    7. Note: Although Reclamation can coordinate with downstream officials
    regarding the affect [sic] that Olympus Dam releases may have on
    downstream flooding caused by inflows below the dam, this EAP and
    the Olympus Dam EWS are for storm events occurring above the dam
    and cannot be relied upon by local officials for storm events occurring
    below the dam.
    17
    (capitalization and emphasis in original; alterations added). At trial, Tim Miller testified that
    “as the water scheduler that day,” meaning September 12, 2013, he “would have followed
    this portion of the Emergency Action Plan as applicable.”
    The Emergency Action Plan further provides for a series of “HAZARD SPECIFIC
    GUIDELINES.” (emphasis and capitalization in original). The “Hazard Specific Guidelines
    state at the outset:
    A. INTRODUCTION
    1. All information contained in the following hazard specific guidelines
    is directed toward actions the dam operating personnel may need to
    take and data they will need to gather to help facilitate decision-
    making directed toward ensuring the structural integrity of Olympus
    Dam and appurtenances for specific incidents that could have an
    impact on the dam.
    2. In all cases, regardless of the incident, the following shall apply:
    a. The first action taken by the dam operating personnel, or anyone
    receiving incoming data from the EWS shall be to implement the
    actions and notification procedures as specified in the Response
    Levels System for Olympus Dam; and,
    b. The dam operating personnel will then implement procedures to
    gather additional data and to preserve the structural integrity of
    Olympus Dam and appurtenant structures as specified in this
    Emergency Action Plan for specific events.
    3. Information presented in the following guidelines is addressed
    primarily at making visual observations, taking instrumentation
    readings, and providing that data to decision-makers in the Eastern
    Colorado Area Office, and Great Plains Regional Office.
    B. REPORT OF              EMERGENCY           SITUATION        OR     UNUSUAL
    OCCURRENCE
    1. A record of all telephone or radio reports of emergency situations or
    unusual occurrences shall be maintained at all steps of the
    communications network. The form on the following page shall be
    used in documenting the report. A supply of these forms should be
    kept on hand and filled out in event of an emergency report or the
    event should be recorded in the logbook. Each call should be
    recorded in a chronological order as necessary to maintain
    continuing records during an incident.
    2. This report shall be considered part of the Operating Log and should
    be accessible at all times.
    (capitalization and emphasis in original). The “Hazard Specific Guidelines” within the
    Emergency Action Plan further provide, under the heading “C. FLOOD OPERATIONS
    OR LARGE RELEASES INTO THE DOWNSTREAM CHANNEL:”
    18
    1. Hazard Identification: There is no flood control space allocation in Lake
    Estes. The hydrologic loading condition, identified as being the most
    critical inflow scenario for warning purposes, is the Probable Maximum
    Flood whose peak discharge is 83,900 ft3/s and whose volume is 79,900
    acre-feet. It has been estimated that failure of the dam from a flood of
    this size would result in a peak discharge of 108,000 ft3/s in the Big
    Thompson River with an average depth of 20 feet.
    2. Operating Personnel:
    a. Flood operating Criteria
    (1) The dam will be attended 24 hours per day when major inflows
    occur which may endanger the safety of the dam and/or
    downstream residents.
    (2) The status of operations in the drainage area above Estes
    Power Plant should be established during an emergency. If
    necessary and conditions permit, dispatch an employee to
    search for a route from the flood area in order to advise higher
    authority of the situation and to re-establish communications.
    (3) When a heavy rainstorm develops in the Rocky Mountain
    National Park, within the Big Thompson River Drainage Basin,
    the Chief Ranger of the park will notify the Estes Power Plant
    Foreman. The Estes Power Plant Foreman will notify the
    Loveland Control Center (LCC),[11] who will relay this
    information to the Water Scheduling Division, Water and Land
    Operations Division, and Power Division of the Eastern
    Colorado Area Office (ECAO). ECAO will notify the Estes Park
    Police Department and Larimer County 24-Hour Warning
    Point that flooding may occur above and below Lake Estes.
    (4) IF OLYMPUS DAM APPEARS TO BE ENDANGERED
    (SUCH AS A SUDDEN SEVERAL FOOT RISE IN LAKE
    LEVEL AND THREATENS TO OVERTOP THE
    EMBANKMENT, immediately contact the ECAO. Information
    to be reported should include current reservoir water surface
    elevation, observed water surface rise rate, weather
    conditions in the vicinity(past, present and predicted), and
    discharge condition of the Big Thompson River above and
    below the reservoir. The ECAO will provide instructions
    regarding reservoir operation and further reporting based on
    this report. Also, immediately open the spillway gates. As long
    as the gates can be opened to increase flows through the
    spillway, there is a good chance of relieving pressure on the
    dam embankment before major damage to the dam occurs.
    11Ralph Beall and Tim Miller testified that, by the time of the events of the September
    2013 storm, the Loveland Control Center had been relocated to the Casper Control
    Center.
    19
    (5)   A calculator program for flood routing is included in the SOP
    [Standard Operating Procedures] at the control house. This
    program will automatically compute changes in storage, inflow
    and outflow rates through Lake Estes, and can be used as a
    tool or aid to assist the operator during times of
    communication loss. This program should be used only by
    experienced operators familiar and competent with operation
    of the calculator and should not be used in lieu of criteria
    written in this Emergency Action Plan.
    (6)   The LCC should notify the Estes Power Plant Foreman to
    contact all employees and schedule shifts for monitoring
    Olympus Dam. These shifts will consist of a minimum of three
    persons per 24 hour day, on a continuing basis, until the
    emergency no longer exists. When the water surface
    elevation at Lake Estes reaches 7,474.00 feet and a further
    increase is indicated, begin opening the No. 3 radial gate
    according to the following criteria:
    (a) Record the elevation at time of arrival.
    (b) Time the lake increase at 15-minute intervals, and record
    the elevation at the end of 15 minutes
    (c) Take the difference of the beginning and ending elevations
    at the end of 15 minute interval and multiply by 10. This
    calculation will provide the change in gate opening for
    radial gate No. 3.
    (d) Continue to operate the gate in this fashion for all
    elevations greater than 7,474.00 feet.
    (e) If the water surface elevation should reach 7,475.75 feet
    and a further increase is indicted, begin opening the
    remaining four radial gats according to these criteria:
    i. Record the elevation at 15-minute intervals.
    ii. Take the difference of the beginning and ending
    elevations at the end of the 15-minute interval and
    multiply by 5. This calculation will provide the range in
    gate opening for the remaining gates.
    iii. If the elevation should exceed 7,475.75 feet (within the
    15 minute interval, use both equations to derive the
    gate settings.
    Note: Gate No. 3 uses a factor of 10 for the gate
    positions. The remaining gates use a factor of 5. These
    factors should not be used interchangeably as excess
    flows will occur.
    iv. When the lake level begins to recede, begin
    decreasing gate openings according to the previously
    mentioned criteria.
    (capitalization and emphasis in original; alteration and footnote added). Tim Miller testified
    at trial that, while the Hazard Specific Guidelines for floods would have been relevant to
    20
    the Bureau’s response to the September 2013 storm, events during the flood could have
    necessitated resort to other Hazard Specific Guidelines as well, such as “erosion,”
    “structural problems,” “failures of different items” including “operational equipment,” and
    “seeps.” Mr. Miller further testified to his belief that, with respect to the Hazard Specific
    Guidelines for floods, in particular, the instructions in paragraph (6) to raise Gate 3 at
    7,474 feet of elevation, and the remaining gates at 7,474.75 feet of elevation, “[t]his whole
    part was null and void during the flood,” for the reason that “Gate 3 was not operable.”
    (alteration added). According to Mr. Miller, under normal circumstances, the Bureau
    would “open Gate Number 3 until it reached the maximum remote operation, and then”
    the Bureau could “bring people to the dam to manually open the other gates or to open
    Gate 3 further” as necessary.
    James VanShaar testified that he would not interpret the Emergency Action Plan
    “as indicating that we should not have opened Gate Number 3[12] until arrival at 7474,”
    and Mr. VanShaar stated that “[o]ther portions of the standing [sic] operating procedures
    gives us flexibility to operate the gates for other reasons and in other ways, and we did
    so.” (alterations and footnote added). Mr. VanShaar also testified, however, that when the
    Emergency Action Plan is triggered, specific Emergency Action Plan requirements trump
    more general rules in the Standard Operating Procedures, and that the Emergency Action
    Plan is followed by operators in the absence of direction from the water schedulers.
    A filled-out version of the form provided for in paragraph B.1. of the Hazard Specific
    Guidelines is included in the record before the court. The form, titled “REPORT OF
    EMERGENCY OR UNUSUAL OCCURRENCE,” indicates that it was completed by
    Howard Bailey, the Bureau’s security officer. (capitalization and emphasis in original). The
    Report of Emergency or Unusual Occurrences provides that Lake Estes reached an
    elevation of 7,473.89 at 11:30 p.m. on September 12, 2013, and that at 11:45 p.m. that
    night, Lake Estes experienced an inflow of 5,391 cfs and outflow of 5,377 cfs. The Report
    of Emergency or Unusual Circumstances further provides a brief summary of the events
    of the September 2013 storm at Olympus Dam:
    Water Scheduler Carlos Lora contacted Emergency Manager Howard
    Bailey at/around 02:00 hrs and notified him of a heavy rain storm in the
    Estes Park area. This rain storm and the subsequent runoff is likely to
    continue raising the reservoir elevation and resulting in increased releases
    from Olympus Dam. Carlos recommended an Internal Alert (IA) that was
    subsequently declared upon consultation with the ECAO IMT. C-BT
    [Colorado-Big Thompson] Facility Manager Ralph Beall was appointed as
    Incident Commander.
    (alteration added).
    12Mr. VanShaar referred to Gate 3 in his explanation of the Emergency Action Plan,
    despite Gate 3 having been inoperable during the September 2013 storm.
    21
    Plaintiffs’ Properties
    Downstream of Olympus Dam, in Drake, Colorado, an unincorporated community
    in the Big Thompson River Canyon, is the confluence of the Big Thompson River and a
    tributary, the North Fork Big Thompson River. The parties stipulated that the North Fork
    Big Thompson River “has a separate watershed from the Big Thompson River,” and
    above the confluence, releases from Olympus Dam do not affect flow in the North Fork
    Big Thompson River. The parties further stipulated that, at the time of the September
    2013 events relevant to the case currently before the court, plaintiffs Howard and Lena
    Carman and Elizabeth Orr were owners of properties on the Big Thompson River
    downstream of both Olympus Dam and of the confluence at Drake, Colorado. The parties
    also stipulated that water released from Olympus Dam takes multiple hours to reach the
    properties of the plaintiffs, although the parties disagree on the approximate number of
    hours from the time of release from Olympus Dam before released water reaches the Orr
    and Carman properties. Because plaintiffs’ properties were both downstream of Olympus
    Dam, in the Big Thompson River Canyon, as well as being downstream of the confluence
    at Drake, the primary events of the September 2013 storm which are relevant to this case
    occurred at Lake Estes and Olympus Dam or downstream thereof. The relevant releases
    from Olympus Dam are all downstream into the Big Thompson River, towards plaintiffs’
    properties.
    The parties stipulated that Ms. Orr owned in September 2013, and continues to
    own, property off Highway 34 in Loveland, Colorado, “more than twelve-and-a-half miles
    downstream from Olympus Dam and more than half-a-mile downstream of the confluence
    of the rivers at Drake.” Ms. Orr testified that at the time of the September 2013 flood, the
    property off Highway 34 was the site of a cabin originally built by Ms. Orr’s grandfather,
    which was expanded in 2003 and 2004 into the structure that existed in September 2013.
    Ms. Orr testified that she has been the sole owner of the property off Highway 34 since
    1976.
    Ms. Orr testified, to her recollection, that the Big Thompson River flooded once
    prior to the September 2013 storm, on July 31, 1976. According to Ms. Orr, during the
    events of the 1976 flood, “it had rained off and on for several days,” but there was not
    “particularly heavy rain in the canyon,” and in the Big Thompson River, “the water level
    was less than in the 2013 [flood].” (alteration added). When asked about the damage of
    the 1976 flood to the property, Ms. Orr testified: “We did lose our septic system, and we
    lost our well, our water well, but there was no damage at all to the house.” Ms. Orr further
    testified that the United States Army Corps of Engineers added “riprapping” to the banks
    of the Big Thompson River following the 1976 flood.
    At the time of the September 2013 storm, Ms. Orr testified that her house was
    located approximately 150 feet from the bank of the Big Thompson River, although the
    older portion of the house, which was built by Ms. Orr’s grandfather, was located closer
    than 150 feet to the river. Ms. Orr’s property is located on the southern, or right, bank of
    the Big Thompson River and was connected to Highway 34 by a bridge over the Big
    Thompson River. At the time of the September 2013 storm, there were multiple structures
    on the property, including Ms. Orr’s house, a barn, a second house identified by Ms. Orr
    22
    as “a play house for our children,” and a playground. According to Ms. Orr’s testimony,
    prior to the September 2013 flood, the Big Thompson River flowed “much closer to the
    highway” than it currently does, and Ms. Orr’s property had a large yard between the river
    and the house, as well as a buried septic system located in front of the house,
    approximately 150 feet from the Big Thompson River, which had been installed after the
    1976 flood. Between the yard and the house were a rock wall, described by Ms. Orr as
    two-and-a-half to three feet high, the driveway that originally led to the older portion of the
    cabin, and a second rock wall. Ms. Orr testified that her house was “15 to 20 feet” higher
    in elevation than the Big Thompson River.
    The parties stipulated that, at the time of the September 2013 flood, Howard and
    Lena Carman, a married couple, owned two adjacent parcels of land on Highway 34 in
    Loveland, Colorado. According to the parties’ stipulations, the Carmans’ home was
    located on one parcel on Highway 34, and on the adjacent parcel on Highway 34 was
    located the business the Carmans owned and managed, the Big Thompson Indian Village
    store (Indian Village store).13 According to the parties’ stipulations, the parcels owned by
    the Carmans “were about fifteen miles downstream from Olympus Dam and at least two
    miles downstream of the confluence of the rivers at Drake,” approximately one-and-a-half
    miles downstream from Ms. Orr’s property. Mr. Carman testified, corroborated by the
    Carmans’ deed to their property, that the Carmans, also owned an access easement over
    the eastern portion of an adjacent parcel, owned by Larimer County, Colorado,
    immediately to the west of the Carmans’ property. According to the testimony of Mrs.
    Carman at trial, the Carmans’ property was approximately 1,000 feet lower in elevation
    than Estes Park. Mrs. Carman testified that the Carmans first moved into their property in
    1971, based on an agreement to lease the property for five years before purchasing it.
    Mr. Carman testified that the Carmans purchased their property in 1976.
    Mr. Carman testified, similar to Ms. Orr, that prior to the September 2013 flood, the
    Big Thompson River had flooded in 1976. Mr. Carman testified that in the 1976 flood,
    falling power lines damaged the back corners of the Indian Village store, and the only
    damage to the Carmans’ house was to the basement, where a “four-foot section” of wall
    and corner “collapsed” and were “knocked out” by the 1976 flood. Mr. Carman further
    testified that the Carmans also lost a “guest cabin” and a barn in the 1976 flood. The
    Carmans purchased their property shortly after the 1976 flood, and the real estate
    contract by which the Carmans purchased the properties indicates that the Carmans were
    aware that the properties “may be located and situate in a flood plain.” At trial, the
    Carmans testified that because the lower portion of their property was located in a flood
    plain, the Carmans did not construct any permanent structures on that portion of their
    land. According to a plat included in the warranty deed which conveyed the Carmans’
    properties to the Colorado Department of Transportation in 2016, the flood plain occupied
    a substantial portion of both parcels owned by the Carmans along the north bank of the
    Big Thompson River.
    13 According to the testimony of Mr. Carman, at the Indian Village store, the Carmans sold
    “Indian stuff, rugs, pottery, jewelry, moccasins,” as well as “T-shirts” and “curio items.”
    23
    The Carmans’ parcels were located on the northern, or left, bank of the Big
    Thompson River, along a bend of the river. The Carmans testified that they had multiple
    structures across the property, including the Carmans’ house, the Indian Village store, a
    large, roughly S-shaped concrete wall which created a higher area of ground on the
    Highway 34 side of the property, as well as a horse trailer and a Connex14 box located on
    the lower portion of the property. On a grassy lawn by the river, behind a horse trailer and
    Connex box, the Carmans kept two horses15 in corrals which at the back were
    approximately four or five feet from the Big Thompson River. Mr. Carman testified at trial
    that at the highest point, the property was approximately 14 or 15 feet higher in elevation
    than the riverbank, and 20 or 21 feet higher in elevation than the water. According to the
    testimony of Mrs. Carman and a map of the property she had drawn, the Carmans’
    property was approximately 200 feet wide at the widest portion, from the parking lot of the
    Indian Village store to the Big Thompson River, while the house and store were
    approximately 75 feet from the Big Thompson River. On the north side of Highway 34,
    across from the parking lot in front of the Indian Village store, was a lower section of
    ground, which Mr. Carman at trial estimated was approximately six feet lower than the
    parking lot of the store and was referred to as the “borrow ditch.” Behind the Indian Village
    store, the Carmans had a footbridge which reached across the Big Thompson River,
    which also carried a pipe which brought non-potable water from a hydroelectric plant
    located across the river.
    Events of the September 2013 Storm
    According to the parties’ joint stipulations, under ordinary circumstances, “[t]he
    Bureau of Reclamation constantly releases water from Lake Estes into the Big Thompson
    River throughout the year,” in order “to serve downstream water rights or environmental
    purposes,” and the Bureau of Reclamation “must release a minimum amount of water,”
    which “ranges between 25cfs and 125cfs depending upon the time of year,” “from behind
    Olympus Dam into the Big Thompson for environmental purposes.” (alteration added).
    The parties also stipulated that in the Big Thompson River Canyon, “[b]eginning at a flow
    level of 1,500cfs, water begins to flood permanent residences,” while most structures “are
    inundated at flows of 6,000cfs.” (alteration added).
    The parties stipulated that, beginning on September 9, 2013, and lasting until
    around September 16, 2013, “significant rainstorms stalled over Larimer County,
    Colorado, including over Olympus Dam and the town of Estes Park.” During the
    September 2013 storm, Estes Park, where Lake Estes and Olympus Dam are located,
    received 11.54 inches of rain, while the average annual rainfall for Estes Park is 16.32
    inches, and the average September monthly rainfall is 1.40 inches. Drake, the location of
    the confluence of the Big Thompson River and North Fork Big Thompson River upstream
    14Mr. Carman testified that a Connex box is “what you see like a semi going down the
    road with.”
    15In the parties’ filings, including the joint stipulations, as well as testimony at trial, the
    Carmans’ animals are described interchangeably as “two horses” and as “a horse and a
    mule.”
    24
    of plaintiffs’ properties, received 16.20 inches of rainfall during the September 2013 storm,
    while the average annual rainfall for Drake is 16.84 inches and, and the average
    September monthly rainfall is 1.50 inches. The parties stipulated that, in total, “15,640
    acre-feet of water flowed into Lake Estes” during the September 2013 storm. According
    to the parties’ joint stipulations, “[t]he peak of the storms” was a 48-hour period “between
    September 11 and 13, 2013:” 3.90 inches of rain fell in Estes Park from 7:00 a.m.,
    September 11, to 7:00 a.m., September 12, and 3.74 inches fell in Estes Park from 7:00
    a.m., September 12, to 7:00 a.m., September 13. (alteration added). The parties’
    stipulations also indicate that “[t]he annual exceedance probability of the September 2013
    storm event ranged as low as 0.1%. In other words, the September 2013 storms may
    have been a 1,000-year storm event.” (alteration added).
    The parties stipulated that on September 12, 2013, multiple emergencies were
    declared by federal, state, and local governments. Also according to the parties’
    stipulations, “then-President Obama declared a federal emergency due to the storms and
    flooding;” “then-Colorado Governor John Hickenlooper declared a disaster emergency
    due to flooding in both Boulder and Larimer Counties;” and “[t]he city manager for the city
    of Loveland, Colorado declared a local disaster on September 12, 2013 due to heavy
    rains, flash flooding, closed roads, and property damage.” (alteration added). According
    to the Post Incident Analysis Report prepared by the Bureau of Reclamation, however,
    “[b]efore and throughout the flood event, the Olympus Dam Early Warning System did not
    transmit any precipitation warnings.”16 (alteration added). According to the testimony of
    Carlos Lora, who was the water scheduler on duty at the East Colorado Area Office of
    the Bureau of Reclamation from the night of September 11, 2013, until the afternoon of
    September 12, 2013, the Early Warning System’s failure to transmit a precipitation was
    not the result of any malfunction in the system, but rather reflected that “the rainfall was
    so slow coming,” and therefore did not trigger a warning.
    Ms. Orr testified that on September 9 and 10, 2013, the area experienced “rain
    showers” and the water in the Big Thompson River near her property was approximately
    two feet below the riprap on its banks. The parties stipulated that prior to approximately
    September 11, 2013, the Bureau of Reclamation “was releasing 80cfs through Olympus
    Dam into the Big Thompson River,” as well as “diverting 560cfs through Olympus Tunnel.
    The water level of Lake Estes was approximately 7,473.2 feet.” Mrs. Carman testified at
    trial that on September 8, 9, and 10, 2013, it was raining “off and on,” including a break
    in the rain the morning of September 10, 2013, and during that time the Big Thompson
    River was not noticeably higher than its normal flow. Based on weather forecasts,
    however, Mrs. Carman testified that she understood that there would be “a large storm
    coming, to expect heavy rain,” especially “through Boulder, Lyons, and Estes Park,”
    upstream from plaintiffs.
    16 The Post Incident Analysis Report states that the Early Warning System at Olympus
    Dam “was calibrated to transmit warnings for extremely intense rainfall events (0.75
    inches in 30-minutes or 1.50 inches in 1-hour). This rainfall event did not exceed these
    intensity thresholds, but other early warning systems elsewhere in Rocky Mountain
    National Park were triggered by the event.”
    25
    According to the testimonies of Tim Miller and Anthony Curtis, the Bureau of
    Reclamation Resources Division chief, a team of water schedulers, operating within the
    Water Resources Group of the Resources Division of the Bureau, direct water releases
    from Olympus Dam, and “develop[] daily water schedules and long-term water schedules
    for movement of water to deliver to participants and contractees” in the C-BT Project.
    (alteration added). According to the testimony of Mr. Miller, the water schedulers’ function
    is to determine at what times and places to release water into the Big Thompson River as
    it is requested by contract holders. Commonly the water schedulers will release water into
    the river at the points where demand for power is the highest, so as to maximize power
    generation with their releases. According to the testimony of Mr. VanShaar, “[t]he Water
    Resources Group is responsible for issuing the water orders” each day, which “describes
    and prescribes the actions to move water through the system,” as well as “oversee[ing]
    portions of the Frying Pan, Arkansas, project, [sic17] and provid[ing] an oversight role for
    the Trinidad project in Southeastern Colorado.” (alterations and footnote added).
    According to Mr. VanShaar, water schedulers rely on “physical and statistical modeling,
    a role for forecasting, data analysis, data issuing,” as well as “maintain the data flow from
    various gauges.”
    According to the testimony of Anthony Curtis, the water schedulers develop water
    orders which “specify the number of acre-feet [of water] to be delivered through each
    facility” of the C-BT based on requests submitted by Northern Water. (alteration added).
    The water schedulers send water orders to a number of entities, including Northern Water
    and WAPA, discussed above, and “the State Engineer’s Office, the district engineers,
    Colorado Parks and Wildlife, and counties and cities within the C-BT,” according to the
    testimony of Mr. Curtis. According to Mr. VanShaar and Mr. Lora, the water order for each
    day typically is released between 3:30 p.m. and 5:30 p.m., and contains a record of the
    instructions from that day as well as prospective instructions for the remainder of that day
    and for the next day.
    At trial, Mr. VanShaar and Mr. Lora testified that the water scheduler on duty for
    September 11, 2013, into the morning of September 12, 2013, was Mr. Lora. Mr.
    VanShaar testified that during the storm, particularly between September 11, 2013, and
    September 13, 2013, the Bureau of Reclamation deviated from the water orders’
    instructions, “[s]ometimes as frequently as once an hour or maybe slightly more frequent,”
    due to changes in the rain and runoff, and accompanying impacts on C-BT Project
    facilities. (alteration added).
    Mr. Lora issued a water order in the afternoon of September 10, 2013, which
    contained prospective changes to flow in the C-BT Project through September 11, 2013.
    The September 10, 2013, water order states:
    The Adams Tunnel flow will be reduced this evening to 450 cfs due to the
    stormy weather impacting the area. Depending on weather condition and
    17“Frying Pan, Arkansas, project” is how the name of that project appears in the transcript,
    however, the name of that Bureau of Reclamation project is actually spelled “Fryingpan-
    Arkansas Project.”
    26
    the runoff situation, we may decide to adjust that flow again tomorrow. The
    reduction will affect Marys and Estes powerplants output.
    Despite the wet weather the region is experiencing today and tomorrow, we
    expect the Adams Tunnel to continue running high flows for the next several
    days. But towards the end of the month, conditions will change, and the
    diversions through Adams Tunnel will have to be reduced. After September
    26th the flow will be reduced to only match demands for C-BT water. The
    reason for the flow reduction late this month is the outages scheduled for
    Flatiron Powerplant unit #3 and for the Charles Hansen Feeder Canal 550
    Section. The annual maintenance for Flatiron unit #3 is scheduled to begin
    on September 23rd and will last 6 weeks, while the Charles Hansen Feeder
    Canal 550 Section work will begin on September 27th and will last only 2
    weeks. Pumping to Carter Lake will likely resume late this week and will
    continue for 7 to 10 days.
    The Estes Powerplant will have 800 acre-feet of water scheduled for power
    generation on Wednesday, a significant reduction from today’s volume.
    Meanwhile, Flatiron units #1 and #2 will have 1,100 acre-feet available.
    The September 10 water order includes among its “summary of flow changes,” at
    midnight, September 11, “[a]djust the Adams Tunnel flow from 500 cfs to 450 cfs,” and at
    7:00 a.m., September 11, “[a]djust the Big T [Thompson] Powerplant flow from 230 to 237
    cfs.” (alterations added). With respect to the order to reduce flow through the Adams
    Tunnel, Mr. Lora testified that “during the day there had been rain in the area, so we
    wanted to make sure that we didn’t go over the capacity of the system.”
    Mr. Carman testified at trial that on September 11, 2013, the Carmans did not open
    their store because the day was forecast to be rainy and cold, and the Carmans believed
    that “people would stay in the house.” Mr. Carman also testified that the water in the Big
    Thompson River on September 11, 2013, was “a little higher” than it would otherwise
    have been, “like a spring runoff,” while Mrs. Carman testified that the river on September
    11 was “[w]ell within its banks.” (alteration added). Ms. Orr testified at trial that on
    September 11, 2013, as late as approximately 8:00 p.m., she drove from Estes Park to
    her property down Highway 34, and at that time “[i]t wasn’t raining hard at all,” while the
    river was “still below the riprap” and within its banks. (alteration added).
    At trial, Mr. Beall testified that, at some point prior to the peak precipitation of the
    September 2013 storm, he visited the Pole Hill Powerplant, the Flatiron Lake Powerplant,
    and the Big Thompson Powerplant. Mr. Beall was unable to identify the specific day or
    days that he visited the powerplants, but he noted that, with respect to the road to the
    Pole Hill Powerplant, a stream which crosses the road “got too large to cross, because
    we ended up stranding one of our work trucks there.” Mr. Beall testified that “we had 550
    [cfs] coming through our power plant in the afterbay, and whatever the gates at the bottom
    of Hells Canyon that was picking up this natural flow was delivering.” (alteration added).
    Mr. Beall states that “PS-2 Jeff Cross and I got personnel together,” and went “back down
    to the bottom of Hells Canyon, and go out in the concrete structure where the stem valves
    27
    are and lower those gates to get us back to 550 at the [Pole Hill] afterbay,” with the intent
    “[t]o close them so they’d quit diverting all the flood water that was coming down Little
    Hells Canyon into our very small afterbay.” (alterations added).
    Moreover, Mr. Beall testified that at Flatiron Reservoir, he observed that
    “Cottonwood Creek, which normally runs very, very small, was bringing enough water into
    Flatiron [Reservoir] that our reservoir elevation was rising, and water scheduling wanted
    us to go check out the elevation circuits, make sure they were reading correct.” (alteration
    added). At the Big Thompson Powerplant, Mr. Beall testified that he disconnected the
    “regular power before it tripped” and “made the decision to get a generator on the deck
    of the power plant and tie it in to the sump pumps,” in order to ensure “that we had
    emergency power for our sump pumps to try and save that power plant.”
    In the afternoon of September 11, 2013, Mr. Lora issued a water order containing
    a summary of that day’s changes and prospective changes to flow in the C-BT Project
    through September 12. The September 11, 2013 water order states:
    The Adams Tunnel flow has now been reduced to 225 cfs due to the rainy
    weather and the high runoff. The change has impacted power generation
    for Marys and Estes powerplants. Inflow to Lake Estes tripled overnight, and
    is now over 300 cfs. With more rain predicted for tonight and tomorrow,
    there is a possibility that the generation for Marys and Estes powerplants
    may have to be curtailed at some point. The situation will be closely
    monitored. Any decisions will be made in a way that allows Western Area
    Power Administration and other parties as much time as possible to adjust
    to the changes.
    Tomorrow at 0900 hours, the Flatiron unit #3 will begin pumping to Carter
    Lake once again. We expect the pump to run between 7 and 10 days.
    The Estes Powerplant will have 520 acre-feet of water scheduled for power
    generation on Thursday, a significant reduction from today’s volume.
    Meanwhile, Flatiron units #1 and #2 will have 1,225 acre-feet available.
    The September 11 water order includes among its “summary of flow changes,” at 7:00
    a.m., September 12, “[a]djust the Big Thompson Powerplant flow from 237 to 385 cfs.”
    (alteration added). The September 11 water order also indicates, in its detailed list of flow
    changes, the instruction to “[m]aintain a flow of 550 cfs,” in the Olympus Tunnel for both
    September 11 and 12, 2013, as well as instructions to “[m]aintain a flow of 75 cfs” of
    releases through the Olympus Dam into the Big Thompson River for both September 11
    and 12, 2013. (alterations added). With respect to the Water Resources Group’s
    motivation for reducing the Adams Tunnel flow, Mr. Lora testified that “we probably
    anticipated that we were going to have a little bit more runoff than we had had the previous
    days.” Mr. Lora further testified that flow in the Adams Tunnel was reduced “to
    accommodate water from the Big Thompson River that was coming into the system,” with
    the result that the powerplants at Marys Lake and Lake Estes would experience reduced
    power generation.
    28
    At trial, Mr. Lora testified that when he left work at the Bureau of Reclamation’s
    Fort Collins office the evening of September 11, 2013, he “called Casper Control Center
    and asked them” to call him if the water in the Big Thompson River above Lake Estes
    reached a flow of 525 cfs. According to the parties’ joint stipulations, the Bureau of
    Reclamation’s response operations to the storm began “just after 11:30 p.m. on
    September 11, 2013,” at which time “no dam operator was present at Olympus Dam.”
    The Bureau of Reclamation’s Operating Log for the events of the September 2013
    storm, kept by the Casper Control Center, is included in the evidence before the court.
    According to the Operating Log as it appears in the record before the court, at 11:40 p.m.
    on September 11, 2013, the gauge in the Big Thompson River above Lake Estes, which
    measured the inflow to Lake Estes from the Big Thompson River, was reading a flow rate
    of 525 cfs, an increase of 200 cfs from 7:00 p.m. earlier that evening. 18 At 11:40 p.m.,
    Casper Control Center called Mr. Lora, pursuant to his earlier instructions. In response,
    Mr. Lora instructed that the inflow from Adams Tunnel be reduced to 30 cfs, from 200 cfs,
    and that the Estes Powerplant, through which water enters Lake Estes from Marys Lake,
    be shut down. According to the parties’ joint stipulations, at that time the Bureau of
    Reclamation reduced the inflows to Lake Estes as Mr. Lora instructed. Mr. Lora testified
    at trial that he “direct[ed] operations from [his] home” the night of September 11.
    (alterations added).
    The Operating Log provides that at 12:18 a.m., September 12, 2013, “Lora called
    to verify Estes [Powerplant] units were off line; notified him that BT [Big Thompson River]
    Above is rising fast (now @ 650 cfs),” and that at 12:19 a.m., “Lora had me [Woodruff,
    the Casper Control Center employee on duty] raise BT Below Oly [Olympus Dam19] Rad
    [Radial] Gate #3 to verify we can control.” (capitalization in original; alterations and
    footnote added). According to the parties’ joint stipulations, a short time after midnight on
    September 12, 2013, the Bureau of Reclamation “began increasing its releases into the
    Big Thompson River via remote operation of a single spillway gate” at Olympus Dam. The
    Bureau would typically do this by remotely controlling Gate 3, the center gate, however,
    as reflected above, Gate 3 “was not in service during the September 2013 storm and the
    Bureau controlled spillway gate number 4 by remote operation.” At trial Mr. Beall
    confirmed that “Radial Gate Number 3 was not operating at the time of the 2013 storm”
    and the Bureau was “using Gate Number 4 in place of number 3 for the Casper Control
    Center to operate” during the September 2013 storm. Mr. Beall testified that instructions
    contained in the Emergency Action Plan for Gate 3 in emergencies would be understood
    to apply to Gate 4, or Gate 2, depending on which gate was under remote operation.
    The Post Incident Analysis Report prepared by the Bureau provides, in relevant
    part:
    18For comparison, according to the testimony of Mr. VanShaar, “the average inflow into
    Lake Estes in September” is “around 75 CFS.”
    19“Olympus," Olympus Dam,” and “Olympus Tunnel” are in some quotations abbreviated
    “Oly,” “Oly Dam,” or “Oly Tunnel.”
    29
    As a precautionary measure, Gate No 3 was taken out of service prior to
    the flood due to a gear box issue. The gear box parts had been ordered and
    had not yet been installed; therefore, Gate No. 3 was not used for the
    duration of this incident. Prior the [sic] flood, Gate No. 4 was transferred to
    remote operation and was operated by CCC [Casper Control Center] up to
    the 2.5 foot limit when the dam operator arrived at the dam. Upon arrival,
    the operator was able to open Gate numbers 1, 2 and 5 to regulate reservoir
    operation per instruction from water scheduling through CCC operators.
    This storm event required opening of 4 of the 5 functioning gates and
    required manual measurement of gate opening for determining operational
    releases from the dam. For a single dam operator this is an arduous task at
    best.
    (alterations added).
    At 12:40 a.m. on September 12, 2013, the Operating Log states: “Per Lora BT
    Below to 180 cfs (+100 cfs); BT Above is now 731 cfs. Carlos [Lora] is calling Burke to
    see if he can get personnel to E [Estes] PP [Powerplant].” (alterations added). At 12:50
    a.m. on September 12, the Operating Log states: “BT Below to 280 cfs (+100 cfs) per
    Lora, BT Above is 796 cfs.” According to the parties’ joint stipulations, during this period,
    the water elevation in Lake Estes rose, and by “1:00 a.m. on September 12, the water
    level of Lake Estes had risen to 7,473.5 feet.” The Operating Log at 1:05 a.m. on
    September 12, states: “BT Below to 380 cfs (+100 cfs).” Mr. Jonathan Haywood, a Bureau
    of Reclamation engineer, testified at trial that he received a phone call from Casper
    Control Center around 1:00 a.m. on September 12, asking Mr. Haywood to “come up and
    operate the [Olympus] dam to alleviate the water coming in.” (alteration added).
    The Operating Log at 1:30 a.m. on September 12, 2013, states: “BT Below to 480
    cfs (+100 cfs); BT Above 1007 cfs.” The Operating Log at 1:35 a.m. further states: “Lora
    called CCC; said to increase more out of BT Below +200 cfs to 680 cfs.” Mr. Haywood
    testified that around 1:45 a.m., he arrived in Estes Park, and he described the weather
    as “torrential rain, like I hadn’t seen before.” The Operating Log at 1:57 a.m. states: “Per
    Lora BT Below to 900 cfs (+220 cfs); BT Above 1145 cfs E [Estes] FB 7473.62.” 20
    (alteration added). According to the testimony of Mr. Lora, between approximately 1:30
    a.m. and 2:00 a.m., September 12, the gauge reading the flow in the Big Thompson River
    below Olympus Dam was lost, and as a result, through approximately the morning of
    September 13, the Bureau of Reclamation did not have an accurate measurement of the
    flow out of Olympus Dam.
    The Operating Log at 2:01 a.m., September 12, 2013, states: “MLPP [Marys Lake
    Powerplant] off (East Portal [Adams Tunnel] flow @ 200 cfs).” (alterations added).
    20The meaning of “FB” in the context of the Operating Log is unclear from the evidence
    before the court. Further, while it is not stated, the figure “7473.62” appears to indicate
    that the elevation of the water in Lake Estes at 1:57 a.m. on September 12, 2013, was
    7,473.62 feet.
    30
    According to the testimony of Mr. VanShaar, Marys Lake Powerplant, through which
    water from the Western Slope flowed before reaching Lake Estes, “has a lower limit of
    about 200 cfs, at which point it shuts off,” but Mr. VanShaar indicated he did not know if
    Marys Lake Powerplant had been turned off by the Bureau of Reclamation or if the
    powerplant had turned off upon reaching its lower limit. According to the parties’ joint
    stipulations, Mr. Haywood “arrived at Olympus Dam at approximately 2:13 a.m. on
    September 12, 2013,” in order to operate the spillway gates, and the Operating Log also
    records Mr. Haywood’s arrival time as 2:13 a.m., September 12. Mr. Haywood testified
    that he “had to operate the gates of Olympus Dam outside” in the rain, and that he was
    “out standing on top of the dam.”
    At trial, Mr. Lora testified that sometime “after midnight” on September 12, 2013,
    he called “the person in charge of declaring those [internal alerts] and woke him up” in
    order to “let him know that we may have to, you know, declare some kind of alert.”
    (alteration added). According to the parties’ joint stipulations, “at approximately 2:30 a.m.,
    the Bureau of Reclamation declared an internal alert at Olympus Dam,” which is “the first
    and lowest of five alert levels at the dam.” According to the Operating Log, the Internal
    Alert was declared “due to high inflows @ BT [Big Thompson River] Above, rain storm in
    area.” (alteration added). Mr. Lora testified at trial that, upon the declaration of the Internal
    Alert at Olympus Dam, he did not “look to the Emergency Action Plan to determine how
    to adjust the outflows from Olympus Dam,” but instead made adjustments “based on
    whatever the inflow at that point was into the dam,” in part because Mr. Lora directed the
    operations of Olympus Dam from his home from the night of September 11 and
    September 12, and he did not have a copy of the Emergency Action Plan at his home.
    According to the parties’ joint stipulations, “[j]ust before 3:00 a.m.” on September
    12, 2013, Mr. Haywood raised each of the four operational gates at Olympus Dam to an
    opening of “approximately six inches.” (alteration added). The Operating Log states at
    2:55 a.m. on September 12: “Haywood going to open all 5 Oly Radial Gates ½’ [foot] per
    Lora ≈ 1100cfs.” (alteration added). At trial, Mr. Lora confirmed that he instructed that all
    five of the radial gates at Olympus Dam be opened one-half foot, for an approximate
    release of 1,100 cfs into the Big Thompson River. According to the testimony of Mr.
    VanShaar, the release effected by Mr. Haywood opening the gates to six inches “would
    certainly qualify” for a declaration of Response Level 1.
    The Operating Log indicates at 3:40 a.m. on September 12, 2013:
    Per Haywood, Oly radial Gate #3 Gear Box is not working [and] there is no
    indication of gate opening – estimate is Gates 1, 2 & 5 are open 1’ [one foot]
    each & gate #4 in CCC [Casper Control Center] indicates 1.39’ [feet] BT
    Below ≈ 1200 cfs; BT Above 1285 cfs E [Estes] FB 73.81.[21]
    (alterations and footnote added). The parties stipulated that the Bureau of Reclamation
    declared Response Level 1 for Olympus Dam at 3:42 a.m. on September 12. According
    21“E FB 73.81” in the Operating Log appears to indicate that the water in Lake Estes had
    reached an elevation of 7,473.81 feet by 3:40 a.m. on September 12, 2013.
    31
    to the parties’ joint stipulations, following this declaration, at 3:45 a.m., the releases of
    water through the spillway gates increased to more than 1,500 cfs into the Big Thompson
    River. The parties’ joint stipulations further provide that the water in Lake Estes by this
    point had risen to an elevation of 7,473.8 feet, leaving 2.4 inches of vertical space in the
    reservoir’s operational pool. The Operating Log at 4:15 a.m. on September 12, 2013,
    states that “Oly Gates 1,2, 4 & 5 are open ≈ 1 ½’ [feet] each,” and 25 minutes later, at
    4:40 a.m., “Oly Gates 1, 2, 4 & 5 are open ≈ 2’ [feet] each, flow of 1400 cfs BT Below.”
    (alterations added).
    According to the parties’ joint stipulations, the Bureau of Reclamation declared
    Response Level 2 for Olympus Dam at 5:15 a.m. on September 12, 2013, indicating
    releases of at least 1,700 cfs, and the Operating Log states at 6:00 a.m. on September
    12: “Per Howard Bailey; Response level 2 @ Olympus Dam; outflows expected to reach
    1700 cfs.” The parties further stipulated that the National Weather Service, at 5:52 a.m.
    on September 12, issued a flood warning for the area including the Big Thompson River
    Canyon and other areas below Olympus Dam. According to the testimony of Mr.
    VanShaar, Response Level 2 was declared “because at that time the outflows [from
    Olympus Dam] were expected to reach 1700 cubic feet per second,” in excess of the
    threshold for Response Level 2 set by the Emergency Action Plan. (alteration added). At
    6:09 a.m. on September 12, Paula Baty22 sent an email to Mr. Bailey, Ms. Lamb, Mr.
    Northrup, Mr. Pedersen, and four others, which indicated that Response Level 2 had been
    declared, and stated that “[o]ur releases are expected to flood cabins in the canyon.”
    (alteration added). At 6:15 a.m., September 12, the Operating Log states: “Per Lora lower
    Oly Gates 1, 2, 4 & 5 to ≈ 1.5’ [feet] each.” (alteration added).
    Mr. VanShaar testified that on the morning of September 12, 2013, “[t]he rain was
    still strong and without break, which is a little unusual for Colorado,” that “[t]his was a
    sustained rain” and “continual,” while “there was limited visibility” in the direction of the
    mountain, and “[t]here were no breaks in the clouds.” (alterations added). Beginning on
    the morning of September 12, 2013, the Water Resources Group “moved from a regular
    eight-hour shift” to alternating shifts of twelve hours on and off, “around the clock, for the
    next several days.”
    According to the testimony of Mr. Carman, on the morning of September 12, 2013,
    the Big Thompson River “was running bank full” and “was coming up on the sides of that
    riprap” near the Carmans’ property. Mrs. Carman similarly testified that the Big Thompson
    River was “flowing pretty heavily,” that it was “two or three feet” below the edge of the
    bank, approximately half of the five to six feet distance from the bottom of the river to the
    banks, and because of the water’s movement “you couldn’t see the bottom of the river.”
    According to Mrs. Carman, because of the increased height of the river and weather
    forecasts, Mr. Carman moved much of his equipment, including his backhoe, out of the
    22As noted above, at trial Ms. Baty, a safety engineer at the Bureau of Reclamation’s
    East Colorado Area Office, went by the name Paula O’Brien.
    32
    lower portion of the Carmans’ property, located in a floodplain, to the higher section of
    their property closer to the highway.
    The Operating Log at 7:10 a.m. on September 12, 2013, states: “Per Carlos [Lora],
    lower BT-below radial gates ¼’ [foot] or 3” [inches] = 1:10 on gate # 4, gates # 1, 3 & 5
    show no indication.”23 (alterations added). At 7:14 a.m. on September 12, the Operating
    Log further states: “Per Carlos [Lora], Take Big-T-PP [Big Thompson Powerplant] off &
    just pass extra water to flow-North (Big-T # 1 off)?” (alterations added). Mr. Miller testified
    at trial that at 7:32 a.m. on September 12, he sent a text message to Mr. Lora and Ms.
    Lamb at the Bureau of Reclamation indicating that the Bureau could begin capturing
    water, and that the Big Thompson Powerplant and the Wasteway24 should be turned off
    to allow the water to be captured at Horsetooth Reservoir.25 Mr. Miller was unaware,
    however, of whether Mr. Lora or Ms. Lamb took his advice and began storing water as
    Mr. Miller had suggested.
    Ms. Orr testified that between approximately 7:30 a.m. and 9:00 a.m. on
    September 12, 2013, she received a recorded emergency “reverse 911” phone call to her
    home landline telephone informing her of the need to evacuate her home.26 According to
    23The Operating Log does not clarify the meaning of “no indication” at 7:10 a.m.,
    September 12, 2013.
    24  At trial, Mr. VanShaar referred to the Wasteway as “the second portion of the
    trifurcation.”
    25 Mr. Miller’s advice to begin capturing water appears to indicate that the Big Thompson
    River was in a “free river condition.” In his testimony at trial, Mr. Curtis defined a “free
    river condition” as one where the water in the river system exceeds the amount of water
    allocated to those holding rights to the water. Mr. Curtis explained at trial that during a
    free river condition, water can be captured from the river system without regard to
    priorities or rights in that water. According to the testimony of Mr. Beall, during a free river
    condition the Bureau can capture water by diverting it via the 550 Section of the Charles
    Hansen Feeder Canal to the Horsetooth Reservoir.
    26 Admitted at trial without objection, but not testified to, is defendant’s exhibit 2006, a
    “Broadcast Detail Report” which states it is “provided by Everbridge” and was described
    by defendant’s counsel at trial as the “certified business records of the Larimer
    Emergency Telephone Authority” documenting “emergency broadcasts to the Big
    Thompson Canyon during the 2013 storm.” The Broadcast Detail Report includes records
    of two emergency calls which appear to have been made in the window of time in which
    Ms. Orr testified she received her “reverse 911” phone call. One “Broadcast Summary”
    included in the Broadcast Detail Report indicates that an emergency call was sent to 183
    “Members” on September 12, 2013, between 7:11:24 a.m. and 8:11:00 a.m. The
    Broadcast Detail Report indicates that another emergency call was made, also on
    September 12, 2013, to 71 “Members,” between 7:21:53 a.m. and 8:21:00 a.m. Both calls,
    according to maps included in the Broadcast Detail Report, were made to locations along
    Highway 34, the highway along which the Orr and Carman properties were located.
    33
    Ms. Orr’s testimony, Ms. Orr did not evacuate her home upon receiving the call, and
    afterwards, based on a conversation she had with an unidentified person who “came
    down as far as they could on Highway 34,” she understood that Highway 34 was out both
    towards Estes Park and towards Loveland, further down the Big Thompson River Canyon.
    Around the time she received the recorded call, Ms. Orr testified that the water in the Big
    Thompson River had risen two feet from its usual height, above the riprap on the bank,
    and had come onto the grassy yard fronting the river on her property. Water from the Big
    Thompson River continued to flow onto Ms. Orr’s property for the remainder of the day,
    while Ms. Orr testified that she remained at her home.
    According to Lake Estes elevation data, jointly submitted by the parties, for the
    period from September 11, through September 13, 2013, at 8:00 a.m. on September 12,
    2013, the elevation of the water in Lake Estes was 7,472.16 feet, approximately 1.65 feet
    lower than its elevation at around 3:40 to 3:45 a.m. that same morning. Beginning
    between 8:00 a.m. and 8:30 a.m. on September 12, the elevation of Lake Estes rose until
    1:30 p.m. on September 12, when the elevation reached 7,473.7 feet.
    The Operating Log at 9:30 a.m. on September 12, 2013, states: “Adams tunnel to
    0 cfs per Carlos [Lora].” (alteration added). Mr. VanShaar testified that this closing of the
    Adams Tunnel gate was the first attempt to stop flows entering from the Western Slope
    of the Continental Divide. At 9:39 a.m. on September 12, 2013, Mr. Lora sent an email to
    Michael Collins, Jacklynn Gould, Charles Pedersen, Ralph Beall, Carlie Ronca, David
    Burke, Howard Bailey, Paula Baty, Adam Northrup, Kara Lamb, and James VanShaar,
    all of the Bureau of Reclamation, which Mr. Lora testified was unusual but done “to inform
    management of what was happening.” In the email, Mr. Lora stated: “1- Last night
    releases from Oly Dam were increased to perhaps as much as 2,000 cfs (estimated). The
    rating for the gage below does not go that high, so the flow could not be measured.”
    (alteration added). Mr. Lora testified at trial that estimation of the releases was necessary
    because the flow gauge below Olympus Dam had been lost between approximately 1:30
    a.m. and 2:00 a.m. on September 12, and was not providing accurate information during
    September 12 and the morning of September 13. In the email, Mr. Lora further stated:
    2- Inflow to Lake Estes exploded rapidly after midnight.
    3- The Adams Tunnel was shutdown at midnight, while the generation for
    Marys ad [sic] Estes Powerplants was stopped.
    4- Four gates were used to chase the flood.[27]
    5- Notifications began just after midnight among ECAO personnel, and later
    expended to outside agencies (Howard [Bailey] and Kara [Lamb]).
    27 At trial, Mr. Lora explained that when the Bureau of Reclamation was “chas[ing] the
    flood,” “[w]e were increasing releases until we were able to match the inflow.” (alterations
    added).
    34
    6- The reservoir level reached 7473.8 ft before we were able to turn it
    around. The upper operational limit is 7474.0 ft.
    7- Currently the reservoir level is approximately 7472.50 ft and we are in the
    process of reducing releases.
    8- We estimate the current reservoir release to be approximately 1,400 cfs,
    although we continue to adjust.
    9- Big T [Thompson] Powerplant is now off. We are now in priority to capture
    Big Thompson River water.
    (alterations and footnote added). Mr. Lora testified at trial that at the time the email was
    sent, “the inflows to the reservoir dropped unexpectedly, and even though we were trying
    to level off the reservoir, it kept dropping and dropping. It’s a very small pool, so it’s very
    reactive.” Mr. Lora further testified that at the time the email was sent, the State of
    Colorado was allowing the Bureau of Reclamation “to capture as much water as we could
    use in the lower part of the system to generate power,” and “we could actually keep the
    water and put it Horsetooth Oregon [sic28] Carter Lake.” (alteration added).
    At approximately 10:00 a.m. on September 12, 2013, Mrs. Carman testified that
    she received a recorded emergency “reverse 911” phone call to her home landline
    telephone, and the call left Mrs. Carman with the impression “that the Olympus Dam was
    going to open one gate and that we were to expect some high water.”29 Mr. Carman
    testified that at approximately 10:00 a.m., water from the Big Thompson River began to
    flow onto the lawn of the Carmans’ properties, and Mr. Carman began relocating items
    from the basement of the Carmans’ house to the first floor, in anticipation of the water
    entering the basement. Additionally, according to Mrs. Carman’s testimony, Mr. Carman
    moved the Carmans’ horses up from the corrals in the floodplain and the Carmans “locked
    them in the yard between the house and the store” at the highest level of the property.
    Mr. VanShaar testified that, around 10:30 a.m. on September 12, 2013, the Pole
    Hill Powerplant, through which water flows when released from Lake Estes via the
    Olympus Tunnel, was experiencing overheating problems. Mr. VanShaar indicated that
    the crew at the Pole Hill Powerplant attempted to keep the plant operational for
    approximately the next hour. Mr. Lora further testified that the Pole Hill Powerplant during
    this time was “tripping,” or going offline, because of the sediment being carried by the
    floodwaters, and that when the powerplant went offline, water could no longer flow
    through it. Mr. Beall also testified that at the Pole Hill Powerplant, “[t]he water was so dirty
    28The trial transcript records Mr. Lora as saying “Horsetooth Oregon Carter Lake.” Based
    on the context in which Mr. Lora was speaking, it is more likely he actually said
    “Horsetooth or in Carter Lake.”
    29 The Broadcast Detail Report included in the record before the court does not appear to
    document a “reverse 911” phone call which was made to the area in which the Carmans
    lived within the approximate time frame stated by Mrs. Carman.
    35
    and carrying so much sediment that it was plugging up our filters, our strainers that we
    use to intake water for cooling water for our bearings as we generate.” (alteration added).
    According to the Post Incident Analysis Report, the Bureau of Reclamation decided
    at approximately 10:30 a.m. on September 12, 2013, “to allow reservoir to rise slightly
    (store water).” According to the testimony of Mr. VanShaar, the Bureau made the decision
    to allow the reservoir to rise because
    [w]e were buying time for our neighbors and our partners to respond to what
    had happened overnight, both the folks that might be trying to get in the
    canyon and get people out. The City of Loveland, which is about seven,
    eight hours downstream of the dam, we were buying time for them to
    respond as best they could. If we could use a little bit of that space and
    delay further increases, we decided to do that.
    (alteration added). According to the Post Incident Analysis Report, at 10:30 a.m. on
    September 12, Mr. VanShaar was “announced as representative to the Loveland EOC
    [Emergency Operations Center]” as well as “technical specialist,” and at this time,
    “[c]ontinuous staffing by an ECAO technical specialist at the Loveland EOC begins.”
    (alterations added). Mr. VanShaar described his work as the ECAO’s representative as
    “interact[ing] with the City of Loveland and their response to help them understand what
    we were doing on the river” for the duration of the storm. (alteration added). Mr. VanShaar
    testified that at that time, the Bureau anticipated further “releases that could threaten lives
    or property,” and that they “were buying time for the emergency response to move
    forward, some of which would have been people to evacuate,” out of concern regarding
    the water the Bureau had already released as well as potentially worsening conditions.
    According to the parties’ joint stipulations, the Bureau of Reclamation declared
    Response Level 3 for Olympus Dam at 11:30 a.m.30 on September 12, 2013, the highest
    response level declared during the course of the September 2013 storm. The parties
    further stipulated that the declaration of Response Level 3 by the Bureau of Reclamation
    did not reflect a belief of “any danger of impending failure of Olympus Dam.” At trial, Mr.
    VanShaar testified that “[w]hen we entered into Response Level 3, we knew we were
    dealing with flows that would impact property and had the potential to impact the safety
    of human life downstream.” (alteration added). Mr. Beall testified that the time between
    the declaration of an Internal Alert and the declaration of Response Level 3, “[e]ight or
    nine hours,” was the shortest such span of time that he could recall. (alteration added).
    The Operating Log, however, does not record the declaration of Response Level 3 until
    1:00 p.m. on September 12, 2013
    The Operating Log at 11:39 a.m. on September 12, 2013, states: “PH [Pole Hill
    Powerplant] #1 to local, taking unit off do [sic] to personnel safety reasons so crew can
    30 Mr. Miller testified that he recalled attending a meeting at which the declaration of
    Response Level 3 was decided, which occurred during “the night of the -- of the 12th,”
    rather than the morning of September 12, 2013, as indicated in the parties’ joint
    stipulations and the Operating Log.
    36
    leave the area.” (alterations added). According to Mr. VanShaar, by 11:46 a.m. on
    September 12, no water was flowing through the Pole Hill Powerplant. Mr. VanShaar
    testified that with the Pole Hill Powerplant shut down, the water in the Olympus Tunnel
    was then rediverted through the Pole Hill Rediversion Structure in Little Hells Canyon,
    and from there into Pinewood Reservoir.
    The Operating Log at 12:00 p.m. on September 12, 2013, states: “Per Carlos [Lora]
    +6” [inches] each Radial gate at Estes dam in 5 min [minute] increments.” (alterations
    added). Mr. Miller testified at trial that “at noon on September 12th,” Olympus Dam was
    releasing “approximately 3400 cfs,” per the notes taken by Mr. Miller contemporaneous
    with the September 2013 flood event. The Post Incident Analysis Report states that “[a]t
    around 1:00 p.m. on the 12th, unusually high local runoff” caused increased flow which
    “raised the water surface elevation of Marys Lake above 8040.0 feet, pushing it into
    Internal Alert.” (alteration added). The Operating Log at 1:00 p.m. on September 12
    states: “Per Carlos [Lora] Oly Tunnel -150 = 400 [cfs] total. Per Howard Bailey Estes is
    now at Response level #3, also Marys is now in an Internal Alert.” (alterations added). At
    trial, Mr. Miller testified that the water schedulers decided to lower the flow through the
    Olympus Tunnel because the Pole Hill Powerplant had been shut down, in order to
    prevent the full 550 cfs flow from entering Little Hells Canyon. Mr. Miller testified that,
    because Marys Lake, which was upstream of Lake Estes, had reached a water elevation
    of 8,040.29 feet, near the top of its operational pool, due to increased flows from the storm
    and triggering an Internal Alert, the water schedulers decided to allow water from Marys
    Lake to pass downstream through the Estes Powerplant and into Lake Estes. The
    Operating Log at 1:10 p.m. on September 12 additionally states: “Per Carlos [Lora]
    increase Oly Radial Gate #4 (3”) & gate #2 (3”).” (alterations added).
    The parties stipulated that as a result of taking the Pole Hill Powerplant offline, the
    Rediversion Structure in Little Hells Canyon was inundated with flows from Olympus
    Tunnel as well as natural inflows. Mr. VanShaar testified that the 1:00 p.m. on September
    12 reduction in Olympus Tunnel flow occurred because “prior to that reduction, the 550
    [cfs] would have been bypassed and landed in that natural channel [Little Hells Canyon],
    where it would have joined with natural runoff from the rain, flowed down to the rediversion
    site,” with the effect that “more water was being diverted into the rediversion than could
    be handled by the infrastructure.” (alterations added). Mr. VanShaar further testified that,
    as a result of the high flows, United States government property, including the “canal
    banks” of the Rediversion Structure, was damaged.
    Mr. Beall explained in his testimony that water had to be diverted away from the
    Pole Hill Powerplant as a result of the influx of sediment, rather than simply shutting the
    power generation off and allowing water to continue flowing through, “[b]ecause it has to
    run through our turbine, and the bearings, when you make electricity, generated a lot of
    heat. The bearings are water-cooled, and that cooling water has protection circuits of flow
    and pressure that will not allow the unit to run unless they’re satisfied.” (alteration added).
    To continue to run water through the turbines while the plant was shut down, Mr. Beall
    testified, would have caused “catastrophic bearing failure.”
    37
    Mr. Beall further testified that “clos[ing] the gates between Pole Hill afterbay and
    Little Hells Canyon” also was done “to prevent the very small levee of the Pole Hill
    afterbay from being overtopped” between Pole Hill Powerplant and Pinewood Reservoir,
    and thereby prevent the levee from sustaining damage. (alteration added). According to
    Mr. Beall’s testimony, the Bureau of Reclamation also sought to “lower the water in the
    930 section [of the Charles Hansen Feeder Canal],” in order to prevent adding water to
    the Trifurcation system near the mouth of the Big Thompson River Canyon, downstream
    of plaintiffs’ property. (alteration added). Mr. Beall further explained that in the previous
    flood in 1976, a siphon located in the Trifurcation tore away after its “supports eroded and
    washed away,” and the Bureau’s “concern was to lower the water in the 930 section so
    that in the event the siphon tore away during this [September 2013] flood, we would not
    be adding water to the river through the 930 section.” (alteration added). Mr. Beall testified
    that “there was already flooding at the mouth of the canyon” near Loveland when the
    Bureau decided to reduce the water in the 930 Section of the Charles Hansen Feeder
    Canal, and the flooding was “from the main fork and the north fork of the Big Thompson
    River, primarily, plus all the rainfall.”31 Mr. Beall indicated that water from the 930 Section
    of the Charles Hansen Feeder Canal would contribute to the downstream flooding in
    Loveland, which is “why we [the Bureau] turned off that source” by stopping additional
    water from flowing into the 930 Section. (alteration added). According to Mr. Beall, the
    decision to stop flows into the 930 Section impacted “the operation of the Olympus
    Tunnel” because “[l]ong term, we have to have Olympus Tunnel closed to quit moving
    water through the 930 [Section] unless we’re pumping to Carter [Lake] with Unit 3 at
    Flatiron.” (alterations added). When asked to clarify that shutting off water flowing into the
    930 Section did not necessitate closing the Olympus Tunnel, because “you [the Bureau]
    would pump that to Carter [Lake],” Mr. Beall answered: “Right. We have – we have done
    that many times, yes.” (alterations added).
    According to the testimony of Mr. Lora, around 3:00 p.m. on September 12, 2013,
    Mr. Lora returned to his home to rest and Mr. Miller assumed water scheduling duties.
    According to the testimony of Tim Miller, after Carlos Lora left, the only schedulers on
    duty at the Loveland office were Tim Miller and Ron Thomasson. The Operating Log at
    3:00 p.m. on September 12 states: “Per Bailey releases out of Oly Dam are now @ 3600
    cfs, still Response level 3.” (alteration added). According to Mr. Miller’s testimony at trial,
    supported by Mr. Miller’s notes taken contemporaneously with the Bureau’s response to
    the September 2013 flood, at 3:00 p.m. on September 12, flows through the Flatiron
    Powerplant were lowered such that power generation was reduced by twenty megawatts,
    while at the Estes Powerplant, flowing into Lake Estes, heightened flows increased power
    generation by five megawatts. The Operating Log reflects the decision to increase flows
    through the Estes Powerplant into Lake Estes, stating at 3:10 p.m. on September 12, “E
    [Estes] #3 on per Miller as Marys Lake is to [sic] full (5 mw’s).” (alterations added).
    At 3:15 p.m. on September 12, 2013, the Operating Log further states: “Oly Tunnel
    -100 cfs = 300 per Miller.” (alteration added). Mr. Miller’s testimony and his
    31 Mr. Beall clarified that, with respect to flooding in Loveland, he did not “know whether
    flooding in Loveland came from other sources besides the Big Thompson River,” and
    stated: “I don’t know where all that water came from.”
    38
    contemporaneous notes, which were admitted as an exhibit at trial, corroborate that the
    Olympus Tunnel flow was decreased to 300 cfs, although Mr. Miller’s notes indicate that
    such decrease occurred at 3:00 p.m. rather than 3:15 p.m. Mr. Miler testified that this
    decrease of 100 cfs was ordered to “reduce the flow through Little Hells Canyon.” Mr.
    Miller further testified that, assuming all other inflows into and outflows from Lake Estes
    remained constant, the effect of reducing flows through the Olympus Tunnel would be to
    increase the elevation of water in Lake Estes.32
    The Operating Log at 6:00 p.m. on September 12, 2013, states: “Oly Tunnel -100
    cfs = 200 per Miller.” (alteration added). At trial, Mr. Miller explained that “we were still in
    bypass [of the Pole Hill Powerplant], over the Little Hells Canyon diversion dam, and it
    [Olympus Tunnel] was just adding more flow to that canyon that didn’t belong there.”
    (alterations added). Mr. Miller testified that the water flowing into Little Hells Canyon “was
    going over the top of that diversion structure,” and that the Bureau employees “weren’t
    able to capture it” in order to “bring it back to Pinewood Reservoir” and the terminal
    reservoirs. Mr. Miller further testified that “assuming all other inflows and outflows
    remained the same,” that “reducing outflows through the Olympus Tunnel” by 100 cfs
    “would have increased” the elevation of water in Lake Estes “by 100 cfs” as a result.
    Mr. Miller testified, supported by his contemporaneous notes from the September
    2013 flood, that at approximately 7:00 p.m. on September 12, 2013, Olympus Dam Gates
    1 and 5 were opened an additional three inches, leading to an increase in releases of 217
    cfs. The Operating Log at 7:15 p.m., September 12, 2013, states: “Per Miller Increase Oly
    Radial Gates by 217 cfs total of ½’ [foot] increase.” (alteration added). According to an
    email, dated September 12, 2013 at 7:52 p.m. and verified by the testimony of Ms.
    O’Brien, at 7:15 p.m., releases from Olympus Dam were approximately 3,800 cfs, while
    “[i]nflow into Lake Estes is estimated to be 3,900 cfs.” (alteration added).
    The Operating Log states at 7:25 p.m. on September 12, 2013, that “Oly Radial
    Gate #1 & Gate #5 increased by 3” [inches] each – total opening 24” [inches].” (alterations
    added). Mr. Miller testified at trial that the “total opening [of] 24” [inches]” on the Operating
    Log reflected the “estimated” amount of the openings of Gates Numbers 1 and 5 by the
    Bureau personnel at that time. (alterations added). The Operating Log further states at
    7:35 p.m. on September 12, “Per Miller @ 2000 CHFC from 450 cfs to 350 cfs.” Mr. Miller
    testified at trial that the entry at 7:35 p.m. on September 12 reflects an instruction he had
    given to reduce flow through the Charles Hansen Feeder Canal, the canal downstream
    of the Big Thompson River Canyon, by 100 cfs at 8:00 p.m. that same day. At trial, Paula
    O’Brien testified that she agreed with the statement, contained in a Bureau of
    Reclamation email from 7:52 p.m., that “[t]he dam is safe and performing well,” (alteration
    added), and Ms. O’Brien explained that “the dam was being operated as we needed it to
    be operated. We were able to pass the flows safely without experiencing any particular
    damage to the facility that could affect the structure or the operation of the facility.” The
    Operating Log further states at 7:55 p.m. on September 12, “[p]er Miller Increase Oly
    32According to the testimony of Mr. VanShaar, no water order was issued in the afternoon
    of September 12, 2013.
    39
    Radial Gates by ½’ [foot] – increase 3” [inches] on Gate #2 & Gate #4.”33 (alterations
    added). Mr. Miller testified, supported by his contemporaneous notes from the September
    2013 flood, that at approximately 8:00 p.m. on September 12, releases through Olympus
    Dam increased by 220 cfs over the amount being released an hour previously, for a total
    approximate flow, as the Bureau estimated at that time, of 4,000 cfs.
    In an email sent by Ms. Baty to East Colorado Area Office personnel, including Mr.
    Northrup, at 8:29 p.m. on September 12, 2013, Ms. Baty stated that “[d]am operators
    have conducted visual inspections” of the Marys Lake Dikes, Olympus Dam, and the East
    Portal Dam, “using the monthly OVIC forms[34] for guidance. There are no issues of
    concern at any of the facilities in terms of the stability of those structures.” (alteration and
    footnote added). Ms. Baty’s email further stated:
    We intend to stay below First Fill at Mary’s [sic] and barring any unforeseen
    equipment issues, are confident that we will be able to maintain control of
    the reservoir level.
    Another issue we are dealing with, that is influencing our flow operations, is
    the condition of the Little Hells [Canyon] Diversion Dam. This is a low hazard
    dam[35] but has significant affect [sic] on our operations of the Pole Hill
    powerplant and the way we run water through the cbt [Colorado-Big
    Thompson] system. If you recall it is associated with the afterbay of the Pole
    Hill powerplant. We have been taking some of the inflows into Lake Estes
    and running them through the Oly Tunnel to minimize river releases.
    33 At trial, Mr. Miller did not fully clarify the meaning of the 7:55 p.m. entry. Mr. Miller
    appeared to indicate that the notation “increase 3” [inches] on Gate #2 & Gate #4” referred
    to an increase of three inches to the named gates in addition to the half-foot increase
    otherwise prescribed for all gates in the 7:55 p.m. entry. (alteration added). Mr. Miller
    stated immediately thereafter, however, “I don’t understand what that means,” referring
    to the 7:55 p.m. entry, and when Mr. Miller was asked by plaintiffs’ counsel, “Is that
    unclear, whether it’s a half-a-foot increase or a three-inch increase?” Mr. Miller
    responded, “Yeah, it is.”
    34At trial, Ms. O’Brien testified that “OVIC” stands for “Observations of Visual Inspections
    Checklist.” She testified to the nature of the OVIC forms and indicated that engineers
    performing inspections with the forms would only indicate a concern on the forms if they
    discovered a change from a prior inspection. Mr. Northrup testified that OVIC forms “are
    checklist forms that dam operators use to inspect a dam, and it’s a guideline form where
    they read a question and they check yes or no.” Mr. Northrup further stated that the OVIC
    form is “put together by engineers to assist dam operators for looking for problems.”
    35Ms. O’Brien testified at trial that “low hazard dam” indicates “that, in the event of failure,
    you do not expect either loss of life, and you don’t reasonably expect loss of, say, a high
    economic value downstream.”
    40
    However, there has been damage to the stoplogs[36] and we have had to
    reduce what we are taking through the tunnel in order to prevent further
    damage. Personnel are in the process of getting to the site to see the
    condition of the structure since we reduced flows.
    (alterations and footnotes added). At trial, Mr. Northrup testified that “[f]irst fill is a water
    elevation on a dam that we’ve never seen before, that the dam has never experienced
    before.” (alteration added). Mr. Northrup stated that first fill37 had previously been reached
    at Olympus Dam, at an elevation of 7,475.25 feet, and at that instance of first fill, Olympus
    Dam did not fail.38
    Mr. Miller testified, supported by his contemporaneous notes, that at approximately
    8:30 p.m. on September 12, 2013, increases through Olympus Dam were increased by
    an additional 220 cfs, however, the Bureau’s estimate of total flow through Olympus Dam
    at this time was revised to 3,800 cfs.39 The Operating Log states, at 8:30 p.m. on
    September 12, “Per Miller Increase Oly Radial Gate #4 by ½’ [foot].” (alteration added).
    The Operating Log additionally states at 9:00 p.m., “Per Miller Increase Oly Radial Gate
    #1, 2, 4 &5 by 3” [inches] each - CCC can only raise Oly Radial Gate #4 to 2.5’ [feet] (BT
    Below ≈ 4100 cfs).” (alterations added). Mr. Miller confirmed in his testimony, also
    supported by his contemporaneous notes, that at approximately 9:00 p.m. on September
    12, releases through Olympus Dam were increased by 300 cfs, for a total flow of
    approximately 4,100 cfs. Mr. Miller explained at trial that, while he requested at 9:00 p.m.
    that all four operational gates be opened an additional three inches, Casper Control
    Center, which was at that time remotely operating Gate 4, could not raise Gate 4 above
    2.5 feet, because “the limiter on that Gate 4 was set to 2.5 feet.” Therefore, Mr. Miller
    testified that at 9:06 p.m. on September 12, Gate 4 was taken off remote control and was
    from that point controlled “by the people onsite” at Olympus Dam. The Operating Log
    documents this change at 9:06 p.m. on September 12: “Oly Radial Gate #4 to LOCAL by
    Lannis.” (capitalization in original). Mr. Miller clarified in his testimony that he “would give
    36Ms. O’Brien at trial described a “stoplog” as “usually a wooden or a metal log that slides
    down into channels such that you’re able to stop the flows at that location.”
    37 “First fill” was described by Paula O’Brien as “the first time that the reservoir has filled
    to a given elevation.”
    38Mr. Northrup’s account of the first fill of Olympus Dam being at the elevation of 7,475.25
    feet is supported by a text message sent at approximately 3:11 p.m. on September 12,
    2013 by Ms. Baty to Mr. Northrup and nine others, which stated: “Oly dam first fill is
    7475.25- we have a few feet there and are avoiding that anyway because of gate 3
    position.”
    39 Mr. Miller indicated at trial that the downward revision of the Bureau’s estimate of total
    flow through Olympus Dam at 8:30 p.m. on September 12, 2013, was due to the Bureau
    “getting a more accurate number of what the gate position opening was.”
    41
    the orders to Casper Control Center, and then they would give the orders to the operators
    who were onsite at the dam.”
    Mr. Miller testified, further supported by his contemporaneous notes, that at
    approximately 10:30 p.m. on September 12, releases through Olympus Dam were
    increased by 340 cfs, for a total release of approximately 4440 cfs. The Operating Log at
    10:30 p.m. on September 12 states: “Oly Radial Gates #1, 2, 4 & 5 raised 3” [inches] each
    per Miller.” (alteration added). Mr. Miller further testified that at 10:40 p.m. on September
    12, there was a further increase of 330 cfs in Olympus Dam releases, for a total release
    of approximately 4770 cfs. At 10:40 p.m. on September 12, the Operating Log states:
    “Oly Radial Gates #1, 2, 4 & 5 raised 3” [inches] each per Miller,” with a total release of
    approximately 4800 cfs. (alteration added). At 10:59 p.m. on September 12, the Operating
    Log states: “Oly Radial Gates #1, 2, 4 & 5 raised 6” [inches] each per Miller ≈ 5300 cfs.”
    (alteration added). At trial, Mr. Miller, again supported by his contemporaneous notes,
    corroborated that at approximately 11:00 p.m. on September 12, releases through
    Olympus Dam were increased, however, Mr. Miller testified that the increase was of 650
    cfs, for a total flow through Olympus Dam of approximately 5,420 cfs.
    According to data collected by the Bureau of Reclamation with respect to the
    elevation of Lake Estes during the September 2013 flood, at 11:15 p.m. on September
    12, 2013, the water in Lake Estes reached an elevation of 7,473.86 feet. According to the
    same data source, fifteen minutes later, at 11:30 p.m., the water in Lake Estes reached
    an elevation of 7,473.89 feet, the highest elevation recorded during the September 2013
    storm. The Standard Operating Procedures for Olympus Dam, the Estes Powerplant, and
    Lake Estes indicate that the storage capacity, or volume of water held, of Lake Estes at
    7,473.8 feet of elevation is 2,442.3 acre-feet of water, while the capacity of Lake Estes at
    7,473.9 feet of elevation is 2,460.0 acre-feet of water, indicating that one-tenth of a foot
    of elevation increase from 7,473.8 to 7,473.9 feet corresponds to an increase of 17.7
    acre-feet of storage capacity. At trial, Mr. Miller calculated, based on the storage capacity
    of Lake Estes provided in the Standard Operating Procedures, that the increase in Lake
    Estes’ elevation from 7,473.86 feet at 11:15 p.m. to 7,473.89 feet at 11:30 p.m. on
    September 12 indicated an increase in storage capacity of 5.31 acre-feet.40 From the
    figure of 5.31 acre-feet, Mr. Miller further calculated at trial, based on a “Reservoir Inflow
    Calculation Sheet” included in the Post Incident Analysis Report prepared by the Bureau,
    that the inflow from 11:15 p.m. to 11:30 p.m. was 257 cfs.
    Mr. Miller testified at trial, supported by his contemporaneous notes, that at
    approximately 11:30 p.m. on September 12, 2013, releases through Olympus Dam were
    increased by 705 cfs, for a total release of approximately 6,125 cfs. The Operating Log
    at 11:35 p.m. states: “Oly Radial Gates #1, 2, 4 & 5 raised 6” [inches] each per Miller ≈
    6100 cfs.” (alteration added). Mr. Miller testified at trial that, “immediately before” he called
    in the order “to release more than 6000 cubic feet per second,” Mr. Miller had a
    40 Mr. Miller testified on cross-examination that, according to the Standard Operating
    Procedures, the storage capacity of Lake Estes does not have “a direct linear relationship”
    with water elevation, but rather a “curvilinear relationship,” and Mr. Miller allowed that it
    was “possible” his calculation of the 5.31 acre-feet increase was inaccurate.
    42
    conversation via phone call with Mr. Bailey, Ms. Ronca, and Mr. Thomasson, at which Mr.
    Miller recommended the increased release. Mr. Miller testified that he “and the other
    participants on the call were aware that at a flow of 6000 cubic feet per second, most
    structures in the Big Thompson Canyon below the [Olympus] dam would be inundated,”
    (alteration added), for which reason Mr. Miller held the phone conversation to discuss the
    potential release. Mr. Miller indicated, however, again supported by his contemporaneous
    notes, that the Bureau “shortly thereafter” revised its estimate of the total release based
    on measurements of Olympus Dam’s spillway gates to 5,280 cfs. Mr. Miller testified that
    the water schedulers had access to a computer system, referred to as “a SCADA,” an
    acronym which Mr. Miller did not define,41 which allowed the water schedulers to
    determine “how much the reservoir, you know, was going up, what it would take
    approximately to, you know, keep it [Lake Estes] from going above that, you know, 7474
    [feet].” (alterations added). Mr. Miller stated that “we just, you know, made our -- our best,
    you know, guess at how much would cause the reservoir to start to, you know, stop rising
    and then start to -- start to decline, and we did exactly that.” Mr. Miller further testified that
    at 11:30 p.m. on September 12, “we had inflow forecasts that were very large” and that
    “we weren’t sure if the rain was going to continue, and we were getting very close to that
    threshold” of 7,474 feet. Moreover, Mr. Miller testified on cross-examination that he
    believed he was “not allowed to” increase the elevation of Lake Estes above 7,474 feet.
    Mr. VanShaar testified that “[a]s we understand and applied the SOP [Standard Operating
    Procedures], we would not have chosen to go above 7474.” (alterations added). Mr.
    VanShaar explained his view that “it was understood by my water schedulers that we
    would not choose to use that extra foot of capacity between 7474 and 7475 purposefully,
    meaning we would make decision that would keep from entering that” buffer space.
    Mr. Miller testified that, while the water schedulers considered increasing flow
    through Olympus Tunnel in response to the water in Lake Estes approaching 7,474 feet
    in elevation, the water schedulers did not do so because of the “physical reason” that
    “[L]ittle Hells Canyon Diversion Dam was overtopping,” and that the Pole Hill Powerplant
    “couldn’t run because it was so plugged up with the strainers, and they were having
    difficulty getting personnel up to the plant to -- to get the plant running again.” (alteration
    added). Mr. Miller further clarified that Little Hells Canyon, where water from the Olympus
    Tunnel would be deposited, is only “a tiny little tributary” with “people’s property all along
    that,” such that sending additional floodwater “could be a very, you know, bad thing to
    do,” and moreover, “there’s nowhere ever [sic] does it say for our project to use flood
    control to send it down another tributary to get rid of the water.” (alteration added).
    The Post Incident Analysis Report prepared by the Bureau contains an estimate
    and correction for the total release through Olympus Dam at approximately 11:30 p.m. on
    September 12, 2013, which is in line with the estimate and correction given by the
    Operating Log and Mr. Miller’s testimony. The Post Incident Analysis Report states at
    41 At trial, Mr. Miller agreed with plaintiffs’ counsel’s characterization of the SCADA as “a
    computerized data acquisition system that collects the data in near realtime from the
    Bureau of Reclamation sensors” in Lake Estes. Mr. Miller further stated that the SCADA
    is “somehow connected to the Western Area Power Administration’s system,” but did not
    specify the nature of that connection.
    43
    11:32 p.m. on September 12: “Water keeps increasing into Lake Estes, now releasing
    6,000cfs.” The Post Incident Analysis Report also states, however, that the “[p]ost-
    incident calculated release is 5,283cfs.” (alteration added). At trial, Mr. VanShaar testified
    that “the analysis after the fact tightened some of the estimates on the openings of the
    reservoir gates,” to produce the lower release figure of 5,283 cfs, while according to the
    parties’ joint stipulations, at the time of release Bureau personnel believed they were
    releasing “a flow greater than 6,000cfs.”
    The Operating Log at 11:41 p.m. on September 12, 2013, states: “Received
    notification from Howard Bailey – notifying of releases from Oly Dam of 6000 cfs.”
    According to the parties’ joint stipulations, at 11:45 p.m. on September 12 peak inflow
    and peak release occurred simultaneously at Lake Estes and Olympus Dam, with inflows
    estimated to be between 5,391 and 5,395 cfs, and releases estimated to be between
    5,280 and 5,377 cfs. The Post Incident Analysis Report states that “inflows into Lake
    Estes peaked between 4600 and 5300 cfs” at approximately “[j]ust prior to midnight,” and
    that “the release from Olympus Dam went as high as 5280 cfs,” which peak release
    “lasted less than two hours” before releases from Olympus Dam began to reduce.
    (alteration added).
    According to the Lake Estes elevation data collected by the Bureau of
    Reclamation, after the increase in releases at 11:30 p.m. on September 12, 2013, the
    water elevation in Lake Estes began to drop, reaching 7,473.87 feet at 11:45 p.m. on
    September 12. There were no additional changes in releases after 11:30 p.m. on
    September 12 for approximately one and a half hours, until around 1:00 a.m. on
    September 13. During this period, releases from Olympus Dam continued at a consistent
    rate of approximately 5,280 cfs. According to the Lake Estes elevation data collected by
    the Bureau of Reclamation, at 11:45 p.m. on September 12 the Bureau was diverting 198
    cfs through Olympus Tunnel. By 12:00 a.m. on September 13, the water elevation in Lake
    Estes dropped to 7,473.82 feet. At trial, Mr. Miller stated that he did not start reducing
    flows out of Olympus Dam at midnight on September 13 because “we weren’t sure if we
    were out of the woods” at that time. The water elevation in Lake Estes continued to lower,
    reducing to 7,473.75 feet at 12:15 a.m., and to 7,473.68 feet at 12:30 a.m. on September
    13. Moreover, according to the Lake Estes elevation data collected by the Bureau of
    Reclamation, which was admitted as a joint exhibit, the water elevation in Lake Estes
    would continue to reduce until approximately 7:15 p.m. on September 13.
    Mr. Miller testified, supported by his contemporaneous notes, that at approximately
    1:00 a.m. on September 13, 2013, the Bureau reduced releases through Olympus Dam
    by 220 cfs, for a total release of 5,060 cfs, down from the revised peak release figure of
    5,280 cfs. The Operating Log at 1:00 a.m. on September 13 states: “Oly Radial Gates #1
    & #2 reduced by 4” [inches] each- per Miller, flow of ≈5000 cfs.” (alteration added). Mr.
    Miller testified that the amount by which the water schedulers decided to reduce outflows
    was not the result of a calculation, but rather reflected a desire to reduce outflows “slowly”
    because “we weren’t sure if there was more to come in and whatnot.” Mr. Miller further
    testified that “during that entire time period between 11:45 p.m. [September 12] and 2:00
    a.m. [September 13],” there were releases “at or above 5000 cubic feet per second
    through the Olympus Dam.” (alterations added).
    44
    The Operating Log at 2:00 a.m. on September 13, 2013, states:
    Per Miller, Oly Radial Gate # 1, 2 & 5 are @ 36” [inches] (-4”). Gate # 4
    started to go closed per Lannis – he raised it back up & now can’t get it to
    raise or lower (currently @ 39”) – Electrician on his way to check situation
    ≈ 4425 cfs.
    (alteration added). The Operating Log at 3:07 a.m., September 13, 2013, states: “Per
    Jonathan [Haywood]; Gate # 4 is now operational and open 36” [inches]. Breaker had
    tripped on overload.” (alterations added).
    According to an email sent by Mr. Lora to Ms. Ronca at 10:28 a.m. on September
    13, 2013, Mr. Lora was back at his office and performing his duties as water scheduler
    by approximately 4:00 a.m. that morning. At 6:58 a.m. on September 13, Mr. Lora sent
    an email to Ms. Ronca stating that as of the morning of September 13, Olympus Dam had
    received 6.5 inches of rain in two days. The 6:58 a.m. email also stated, in relevant part:
    3- Lake Estes release up to 5280 cfs last night, back down to 4,300 cfs.
    Reservoir level is dropping slowly. Current inflow is 4200.
    4- Fate of Pole Hill’s afterbay and Little Hells Canyon facilities unknown but
    suspected damaged.
    5- Olympus Tunnel flow down to 190 cfs.
    6- Signal from Dille Tunnel diversion structure and from the Canyon Mouth
    gage [sic] are lost.
    7- Flatiron Powerplant still generating power. Unit #3 stopped pumping last
    night at 0100 hours (not enough water).
    8- We are in priority to capture Big Thompson River water, but given the
    situation that is being done on a limited basis. Water is now been sent to
    Horsetooth.
    (alteration added). The Operating Log at 7:00 a.m. on September 13, states: “BT [Big
    Thompson] crew reports BT PP [Powerplant] has taken on water.” (alterations added).
    The Operating Log at 7:55 a.m. further states: “Received a call from Howard Bailey BT
    Below peak flow last night was 5280 cfs – current flow is 4200 cfs.”
    The Operating Log at 11:40 a.m. on September 13, 2013, states: “Oly Operator
    reports 4 Oly gts [sic] 30” [inches].” (alterations added). At 11:59 a.m. on September 13,
    Ms. Baty sent an email to Mr. Northrup, Mr. Beall, Mr. Bailey, Ms. Lamb, and thirteen
    others, who were not identified at trial, which stated that “Olympus Dam, Mary’s [sic] Lake
    Dike, and East Portal Dam visual inspections today revealed no concerns. We maintain
    a R3 [Response Level 3] at Olympus [Dam] and still an Internal Alert at Mary’s [sic] Lake,
    although the elevation has dropped below the trigger.” (alterations added). The 11:59
    a.m. email further states, in relevant part:
    45
    We have experienced damage to the [Little] Hell’s Canyon Diversion Dam
    stoplogs, and flows through the Olympus Tunnel were reduced to 200 cfs,
    as a result. We have not since been able to get into that location to evaluate
    damage further. We are also restrict [sic] from being able to access Pole
    Hill powerplant right now.
    The Big Thompson River is eroding around the concrete supports for the
    siphon that spans the River, carrying the Charles hansen [sic] Feeder Canal
    flows to Horsetooth Reservoir.
    (alterations added).
    The Operating Log at 1:00 p.m. on September 13, 2013, includes two entries
    regarding Olympus Dam and Olympus Tunnel: “Per Lora Oly gts [sic] -3” [inches] = 27”
    (Gates (1, 2, 4 & 5)” and “Per Lora Oly Tunnel -100 = 100 cfs.” (alterations added). The
    Operating Log at 2:00 p.m. on September 13 further states: “Per Lora Oly Tunnel -100 =
    0 [cfs].” (alteration added). At 3:04 p.m. on September 13, Ms. Baty sent an email to Mr.
    Northrup, Mr. Beall, Mr. Bailey, Ms. Lamb, and thirteen others, which stated: “Once flows
    have subsided, we will be conducting thorough evaluations for damage at each site.” 42
    The Operating Log at 3:34 p.m. on September 13 states: “Per Howard Bailey Big T
    [Thompson] River is at 2780 cfs.” (alteration added).
    Mr. Miller issued a water order in the afternoon of September 13, 2013, which
    appears to contain information for September 12 and 13, 2013, and did not contain
    prospective information for September 14, 2013. The September 13 water order appears
    to provide information regarding flow changes that occurred on September 12 noting
    “[m]aitain a flow of 75 cfs” with respect to releases from the Olympus Dam into the Big
    Thompson River, and “[m]aintain a flow of 550 cfs” with respect to Olympus Tunnel.
    (alterations added). The information for September 12 in the September 12 water order,
    however, appears to be identical to the information for September 11 and 12, 2013
    included in the September 11 water order. Moreover, the September 13 water order
    states:
    The inflow to Lake Estes has started to recede. Our current plan is to
    continue reducing the releases from Olympus Dam as the inflow recedes.
    The Estes Powerplant will have 260 acre-feet of water scheduled for power
    generation on Friday [September 13]. Meanwhile, Flatiron units #1 and #2
    will have 520 acre-feet available.
    (alteration added). The September 13 water order, in its “summary of flow changes,”
    further states:
    42Mr. Northrup testified at trial that he conducted the evaluation with respect to Olympus
    Dam.
    46
    Friday, 0100 hrs             Stop Flatiron Unit #3 Pumping to Carter Lake.
    Friday, 0100 hrs             Adjust the Olympus dam release to the Big T
    [Thompson] river from 5280 cfs to 5060 cfs.
    Friday, 0200 hrs             Adjust the Olympus Dam release to the Big T
    river from 5060 cfs to 4574 cfs.
    Friday, 0300 hrs             Adjust the Olympus Dam release to the Big T
    river from 4574 cfs to 4425 cfs.
    Friday, 0400 hrs             Adjust the Olympus Dam release to the Big T
    river from 4425 cfs to __ [sic] cfs.
    (alterations added). The September 13 water order further details flows for entirety of
    September 13, including the notations “[n]o flow” for the Big Thompson Powerplant and
    “[n]o generation” for the Pole Hill Powerplant, and the instruction to “[m]aintain a flow of
    200 cfs” through the Olympus Tunnel. (alterations added).
    The Operating Log at 5:48 p.m. on September 13, 2013, states: “Per Lora Oly gts
    [sic] -6” [inches] = 21” ea.” (alterations added). The Operating Log at 8:00 p.m. on
    September 13 further states: “Per Lora – if Lake Estes elevation reaches 7469.7’ [feet] –
    call Estes (Oly) and lower all gates #1, #2, #4, #5 -.25’ (current elev. 7469.78’).” (alteration
    added). The Operating Log at 8:53 p.m. on September 13 additionally states: “Oly Dam
    gates #1, #2, #4, #5 -.25’ [feet] verbal per Miller.” (alteration added). Seven minutes later,
    at 9:00 p.m. on September 13, the Operating Log further states: “Per L [Lora], Miller Oly
    Dam Rad [Radial] Gates #1, #2, #4, #5 @ 18” [inches] EA (-3” = .25’ [feet]).” (alterations
    added). The Operating Log at 11:10 p.m. on September 13 states: “Per Tim Miller – Oly
    Dam Rad [Radial] Gates #1, #2, #4, #5 +3” [inches] ea.” (alterations added). Five minutes
    later, at 11:15 p.m., the Operating Log further states: “Per L [Lora], Miller – Oly Dam Rad
    Gates #1, #2, #4, #5 to 21” = +3” ea.” (alteration added).
    According to the parties’ joint stipulations, for an approximately 24-hour period
    from shortly before 12:00 a.m. on September 12, to shortly before 12:00 a.m. on
    September 13, 2013 the water coming into Lake Estes, including inflows, runoff, and
    rainfall, exceeded the water being released through the spillway gates of Olympus Dam,
    and as a result, the water elevation in the Lake Estes reservoir rose to 7,473.89 feet by
    11:30 p.m. on September 12, the highest elevation which the reservoir would reach during
    the 2013 storm. The parties stipulated that at 11:30 a.m. on September 12, inflow into
    Lake Estes reached 3,903 cfs, while releases through the spillway gates amounted to
    2,128 cfs, a difference of 1,775 cfs, the largest disparity between Lake Estes inflows and
    Olympus Dam releases documented during the September 2013 storm. Mr. Miller testified
    that he understood during the events of the September 2013 flood that water released
    from Olympus Dam would take approximately three to four hours to reach the mouth of
    the Big Thompson River Canyon downstream.
    While the Bureau of Reclamation’s elevation gauge for the water in Lake Estes
    remained operational throughout the duration of the storm, the gauges relied on by the
    47
    Bureau to measure flow into Lake Estes and releases from Olympus Dam “washed out
    or became unreliable due to the intensity of the flow.” As a result, Bureau employees
    calculated inflows and releases according to “a mass-balance equation based upon the
    elevation level of Lake Estes and the opening of Olympus Dam’s spillway gates.” 43
    Bureau employees did not constantly measure the spillway gate openings over the course
    of the storm, but the “water schedulers initially calculated certain inflows and releases
    based on the dam operators’ estimations of gate openings,” with such estimates being
    revised as measurements of the spillway gate openings were made. As a result, “the on-
    duty water scheduler initially believed, and the Bureau then adopted and reported, that
    peak release from Olympus Dam was a flow greater than 6,000cfs.” At the time of the
    September 2013 storm, according to the Bureau’s Standard Operating Procedures and
    Emergency Action Plan, and the parties’ joint stipulations, the Bureau understood that at
    a flow of 6,000 cfs, water would inundate structures in the Big Thompson River Canyon.
    When the spillway gate measurements for peak release were reported, estimates for peak
    release from Olympus Dam were revised to approximately 5,300 cfs.
    The parties stipulated to four sources of water which contributed to the flow at the
    plaintiffs’ properties:
    (1) releases from Olympus Dam; (2) rainfall and runoff from the area
    between the dam and the confluence of the Big Thompson and North Fork
    Big Thompson Rivers at Drake; (3) the North Fork Big Thompson River; and
    (4) rainfall and runoff from the area between the confluence at Drake and
    Plaintiffs’ properties.
    According to the parties’ joint stipulations, at the Orr property, peak flow of the Big
    Thompson River reached between 14,800 and 15,011 cfs, while peak flow by the Carman
    property reached between 14,800 and 15,080 cfs. The parties also stipulated that more
    than 9,400 cfs of the peak flow at plaintiffs’ properties are attributable to sources other
    than Olympus Dam releases.
    According to the parties’ joint stipulations and the testimony of Mr. Carman, at
    approximately 11:00 a.m. on September 12, 2013, water from the Big Thompson River
    entered the basement of the Carmans’ home. The Carmans’ properties lost power “a little
    after lunch,” and between approximately 2:00 p.m. and 3:00 p.m., the Carmans lost phone
    service as well. At approximately 2:00 p.m., a “HUMV vehicle” arrived at the Carmans’
    properties, and Mr. Carman spoke with one of the men from the vehicle and was left with
    the impression that the Carmans “were going to have high water,” but not that they
    needed to evacuate. By between 2:00 p.m. and 3:00 p.m., water from the Big Thompson
    River was flowing across the Carmans’ lawn between the river and their home. By the
    evening of September 12, 2013, the Carmans’ footbridge over the Big Thompson River
    had washed away. Mrs. Carman testified that by 6:00 p.m. on September 12, the water
    43Mr. VanShaar testified that “on the evening of September 12, 2013, the estimated inflow
    to Lake Estes would have been calculated through mass balance principles. Inflows,
    whatever they are, all of them, minus outflows, that’s releases to the river and flows
    through the Olympus Tunnel, equals the change in storage.”
    48
    in the Carmans’ basement had reached a depth of three to four feet. Mr. and Mrs. Carman
    testified that in the late afternoon or early evening of September 12, the Carmans went
    for a drive up the Big Thompson River Canyon as far as Drake and Waltonia, Colorado,
    and according to the testimonies of Mr. and Mrs. Carman, they did not see water on the
    road. Upon returning from this drive between approximately 6:30 p.m. and 7:00 p.m.,
    according to Mr. Carman, the Carmans gathered a laptop and toiletries and relocated to
    their neighbor’s house on higher ground across Highway 34 and did not see their property
    again until the next morning. When the Carmans last saw the water before departing their
    house, the water had risen to between a foot and a foot-and-a-half deep in the yard behind
    their house and the Indian Village store.
    Between approximately 11:00 p.m. and 11:30 p.m. on September 12, 2013, Ms.
    Orr, who had been at her home for the entirety of the day of September 12, testified that
    she could no longer see the level of the river because of the darkness at that time of night,
    but the last time she had seen the river, “it wasn’t anywhere close to the house,” and
    remained in the grassy yard. At this time, Ms. Orr testified that she heard “a roaring sound
    of water coming down,” which was different from earlier in the day, when the river had
    been quiet. At approximately 11:30 p.m. on September 12, the parties stipulated, and Ms.
    Orr testified, that Ms. Orr observed “the Big Thompson River rapidly rise out of its banks
    onto her property” and “overturn her picnic table, which had been set in concrete.” In
    response, Ms. Orr evacuated her property to the house of two neighbors, the Swedlunds,
    and did not see her property again until the morning of September 13.
    Mrs. Carman testified that at approximately midnight or 1:00 a.m. on September
    13, 2013, she heard the river “rumbling and things rolling around the rocks.” Mr. Carman
    further testified that between approximately midnight and 2:00 a.m. on September 13, he
    heard his backhoe, with its outriggers extended, dragging across concrete. Ms. Orr
    testified that at approximately 2:00 a.m. on September 13, while Ms. Orr could not see
    her house from the Swedlunds’ property, she could hear “crackling” as well as “things
    coming down the river,” and she “could smell propane.” Ms. Orr testified that she could
    hear “noises during the entire night because of the water, the rush of the water hitting the
    boulders and things in the river that were bouncing against the boulders” as well as the
    crackling. According to the parties’ joint stipulations, between approximately 3:00 a.m.
    and 4:00 a.m. on September 13, Mr. Carman “heard ‘rocks rolling in the bottom of the
    creek’” which he attributed to erosion caused by the flooding.
    Ms. Orr testified that she left the Swedlunds’ house at approximately 5:30 a.m.,
    September 13, 2013, and returned to her property, where she found, according to the
    parties’ joint stipulations, “that the flood had eroded the banks of the Big Thompson River
    including the real property under and adjacent to her house, which had been damaged.”44
    44 Ms. Orr submitted a claim to the United States for the loss of her property by email on
    September 7, 2015. In the email, Ms. Orr stated that the portion of the house which fell
    into the river was lost at approximately 3:00 a.m. on September 13, 2013. At trial, Mr. Orr
    testified that the 3:00 a.m. time was only an estimation, and that she does not know what
    time the portion of the house collapsed.
    49
    At this time, the water had receded and the grassy lawn which previously fronted the river
    had washed away, while the portion of Ms. Orr’s house nearest the river had collapsed
    into the river and much of the ground between the river and the house had eroded away,
    and the remainder of the house was left atop a ledge which Ms. Orr testified was
    approximately 20 feet high. Ms. Orr was evacuated by helicopter on September 15, 2013.
    As of the filing of plaintiffs’ complaint in this court, Ms. Orr continues to own, and is able
    to visit, her property, and the Big Thompson River has not flooded Ms. Orr’s property
    since the September 2013 flood.
    According to the parties’ joint stipulations and the testimony of Mr. Carman, by
    8:00 a.m. on September 13, 2013, the Carmans saw that their store had washed away
    and water from the river was flowing behind and in front of their home, but the water was
    too high to reach the properties. The parties stipulated, and Mr. and Mrs. Carman testified,
    that at approximately 10:00 a.m. on September 13, Mr. and Mrs. Carman returned to their
    property and found the house still standing, along with their two horses in the fenced-in
    yard between a tree and the front door of the house. Mr. and Mrs. Carman attempted to
    get the horses out of the fenced-in yard by clearing debris blocking the horses’ exit from
    the yard, however, a hole opened beneath the Carmans’ home, into which the Carmans’
    horses and home fell and were lost. According to Mrs. Carman, when the hole opened
    up, Mr. Carman, who had been closer to the horses, “was standing about two feet from
    the bank,” after the ground in front of him dropped away. Afterwards, the Carmans
    returned to their neighbor’s house on higher ground.
    According to their testimony at trial, Mr. and Mrs. Carman remained at their
    neighbor’s house until September 14, 2013, when they were evacuated by helicopter at
    approximately 5:00 p.m. By the time of the Carmans’ evacuation, water levels around the
    Carmans’ properties had begun to recede. Upon returning to the properties approximately
    two weeks after the flood, Mr. Carman found that nothing remained of the store, and that
    only a portion of the floor, a piano, and a couch remained of the Carmans’ home, as
    documented by pictures taken by Mr. Carman and admitted as joint exhibits at trial.
    Additionally, the S-shaped concrete wall, the Connex box, the horse trailer, and the
    corrals remained on the properties. Without their store, the Carmans could not afford to
    continuing owning their properties, and the Carmans sold their properties to the Colorado
    Department of Transportation to replace a portion of Highway 34 lost in the flood,
    memorialized in a warranty deed dated August 19, 2016.45 Subsequently, according to
    Mr. Carman’s testimony and the parties’ joint stipulations, the Carmans stayed with their
    daughter for a period of time, and ultimately moved to Cortez, Colorado. According to
    Mrs. Carman’s testimony, the Carmans’ property was not flooded again by the Big
    45 At trial, Mr. Carman testified that, after the September 2013 flood, the Carmans
    “couldn’t afford to pay the taxes” assessed by Larimer County against their property, “and
    the State Highway come along and said we need to purchase that piece of property” in
    order “to put the highway there.” Mr. Carman further testified that the Carmans accepted
    the offer to sell their land because otherwise the “county would have taken the property
    away from me.”
    50
    Thompson River at any point between the September 2013 flood and when the Carmans
    sold the property in 2016.
    Danger to Olympus Dam During the September 2013 Storm
    With regard to dam failures, the parties’ stipulations indicate that dam failures can
    lead to loss of life, and two modes of failure pose a risk to Olympus Dam: “(1) failure of
    the embankment dam from overtopping of its crest; and (2) sliding of the concrete gravity
    dam from high pool elevation levels or high flows.” The parties’ stipulations further indicate
    that “[o]vertopping of the embankment portion of Olympus Dam could result in severe
    erosion, breach, or failure.” (alteration added). Witness testimony at trial additionally
    indicates that as a result of the Bureau of Reclamation’s actions, Olympus Dam was not
    put in danger of a breach or of failing during the September 2013 storm. Mr. Beall testified
    that “lots of dams were in danger and lost during this event. So Olympus Dam was in
    peril, but we mitigated the risk through our actions” during the storm. Mr. Beall stated his
    understanding “that the event with huge flows at the peak of this storm coming into Lake
    Estes would have – obviously puts infrastructure in danger, and that’s why we had to man
    it 24/7 and mitigate that danger by matching releases. Our lake elevation was at a safe
    level.” At trial, at the prompting of plaintiffs’ counsel on direct examination, Mr. Beall read
    from a portion of his earlier-given deposition testimony, in which Mr. Beall stated his belief
    that “[t]here was no emergency at Oly[mpus] Dam. The dam was not in danger. It’s our
    job to protect the dam.” (alterations added). Mr. Beall further read from his deposition a
    portion in which he stated, “in my opinion, the dam was never in jeopardy thanks to the
    actions we took.” Mr. Beall also testified that during the event, he did not tell anyone “that
    the dam was in danger” during the September 2013 flood. Mr. VanShaar testified that “[a]t
    no time did we expect the dam to fail.” (alteration added). Although she identified both a
    breach and overtopping of Olympus Dam as potential structural problems, Ms. O’Brien
    testified that during the September 2013 flood, she did not identify any structural problems
    at Olympus Dam aside from a broken gearbox which prevented the use of Gate 3.
    As noted above, the Emergency Action Plan for Olympus Dam in effect at the time
    of the September 2013 flood provides for “Hazard Specific Guidelines” which specifically
    address operations during a flood event. At trial, Mr. Beall testified that an occurrence
    provided for in the “Hazard Specific Guidelines” for floods, a “sudden several foot rise in
    lake level,” did not occur during the September 2013 flood. Mr. Beall further indicated in
    his testimony that the Emergency Action Plan did not require the Bureau of Reclamation
    to wait until the elevation in Lake Estes had reached 7,474 feet to begin opening Gate
    Number 3, or the applicable remotely-operated gate, and to wait until the elevation had
    reached 7,474.75 feet to begin opening the remaining gates. Rather, Mr. Beall stated, “I
    read this [the Hazard Specific Guidelines for floods] like you would a speed limit. Don’t
    drive faster than 55, but you can drive 45. So it tells me I must do this at this point. It
    doesn’t tell me I can’t do it before.” (alteration added). Mr. Beall was unable at trial to
    identify where in the Standard Operating Procedures, Emergency Action Plan, or other
    documents, were instructions for opening the spillway gates in an emergency situation
    before elevation reached 7,474 feet. In his testimony, Mr. Beall agreed that the intent of
    the Emergency Action Plan’s Hazard Specific Guidelines for floods was to open the
    spillway gates “to an amount that won’t allow the dam to overtop.”
    51
    Mr. Beal further testified that the “priority of the Incident Management Team” was
    “to ensure the safety of the [Olympus] dam and to make sure it was not compromised,”
    to the exclusion of concerns such as electricity generation and water storage. (alteration
    added). Mr. Beall further testified that “making releases from Olympus Dam” was “part of
    the incident management’s [sic] team’s effort to ensure the structural integrity of Olympus
    Dam,” and stated, “[t]he dam positively would have overtopped,” if no releases were made
    during the September 2013 flood. (alterations added). According to the parties’
    stipulations, the Incident Action Plan prepared by the Bureau on September 12, 2013,
    indicates that one objective of the Bureau’s response was “‘Priority to protect Olympus
    Dam which protects downstream property and lives.’” At trial, Mr. Curtis testified that the
    Bureau of Reclamation “sustained damage below Olympus Dam, damage to the Dille
    Diversion Structure,” damage to the “support functions” of the “siphon that crosses the
    Big Thompson River,” “damage to the Big Thompson Powerplant, and to the outlet feature
    of the Pole Hill Powerplant,” and the power plants had to brought offline.
    Mr. Beall testified that, after the September 2013 storm, he visited “Pole Hill, Hells
    Canyon, trifurcation [sic], Big Thompson Powerplant, Estes, [and] East Portal.”
    (alterations added). Mr. Beall stated that “[a]t the bottom of Little Hells Canyon, the water
    level had become so high that as it went over our timbers that I talked about before, it
    eroded out at downstream to rock.” (alteration added). Further, “the upstream portion had
    several feet of rock, mud, and debris, silt that had came [sic] down and settled in the
    bottom of Little Hells Canyon.” (alteration added). Mr. Beall testified that there was “[n]o
    damage at trifurcation except that siphon that transitions from the 930 [section] to the 550
    [section] of the Charles Hansen Feeder” Canal, in particular damage to the supports of
    the siphon. (alterations added). Further, with respect to damage at the Big Thompson
    Powerplant, Mr. Beall testified that he was
    [v]ery surprised to find out that the entire plant wasn’t flooded. We had some
    mud and water in the bottom. We have an external building that’s a battery
    room and some control equipment that had several feet of mud in it. We
    have an excitation transformer that’s mounted on top of the power plant
    deck that had lots of mud and debris.
    A big log had poked a hole in the stairway that goes -- the siding of the
    enclosed stairway that goes down to the power plant. And then the other
    thing was the afterbay, where our water exits the power plant, was several
    feet of earthen soil.
    (alteration added). Mr. Beall testified, however, that “shutting down the Olympus Tunnel”
    did not diminish the damage to the Big Thompson Powerplant, because “[t]his damage
    was due to the water at the mouth of the Big Thompson Canyon,” while similarly there
    was “no correlation” between the closing of the Olympus Tunnel and the damage to the
    Trifurcation. (alteration added).
    Mr. Northrup testified that on September 17, 2013, he performed an inspection of
    Olympus Dam. According to an email Mr. Northrup sent at 12:34 p.m. the following day,
    September 18, 2013, to Ms. Baty, Mr. Northrup stated: “I walked Oly dam with Jon
    52
    Haywood. From visual inspection, the dam is in good condition. The water elevation at
    the time was 7470.53. Gate 1 was just closed, Releases were being made out of Gates
    2,4,5.” Mr. Northrup testified at trial that, according to his inspection, “the dam had not
    shifted at all” during the September 2013 storm. Mr. Northrup further testified that he
    found “minimal erosion,” he was not “concerned with seepage” from the dam, that he
    found “no large or new cracks” in the dam, and that there were “no signs of stress from
    the storm” on the trunnion joints of the radial gates.
    Mr. Northrup testified that his September 17, 2013 inspection of Olympus Dam
    was also documented by a formal report, which he sent to Mr. Pedersen. Mr. Northrup
    further testified that later, “more comprehensive reviews or inspections of the dam” had
    occurred, but those inspections “did not turn up any further problems that I may have
    missed.” At trial, when testifying to the findings of his inspection, Mr. Northrup stated that
    “[f]rom a dam safety perspective, we are comfortable with water under 7475.25” feet of
    elevation, and he clarified: “that refers to the first fill elevation, and we are comfortable
    with the dam’s performance of water on the structures up to that elevation.” (alteration
    added). Mr. Northrup further indicated, however, that while Olympus Dam had previously
    reached a first fill elevation of 7,475.25 feet without overtopping with all gates open, the
    water would begin to overtop the Olympus Dam gates at an elevation of 7,475 feet if the
    gates were closed, resulting in “[a]n uncontrolled reservoir release.” (alteration added).
    Mr. Northrup explained that “if the Bureau of Reclamation had a first fill condition at
    Olympus Dam during the September 2013 storm event, water would have overtopped the
    closed Gate 3,” because Gate 3 was closed for the duration of the storm.
    At trial, Mr. VanShaar testified that “the primary goal” of the water schedulers “was
    to pass the large amount of flows that entered Lake Estes through the dam in a safe
    manner.” Mr. VanShaar testified that “from the very bottom of the regulatory storage” of
    Lake Estes, to an elevation of 7,474 feet, there is approximately 700 acre-feet of storage,
    while “approximately 1100 acre-feet” move through Lake Estes in a day when Olympus
    Dam is running at capacity. Mr. VanShaar further stated that during the storm he
    calculated that if inflows exceeded outflows by 1000 cfs, then a foot of regulatory storage
    in Lake Estes would be filled in one-and-a-half to two hours. Mr. VanShaar testified at trial
    that during the storm, he believed that without the Bureau of Reclamation making the
    releases that it did, Olympus Dam would have overtopped. Mr. VanShaar also stated,
    however, that during the storm he never “believed Olympus Dam was in danger,” nor did
    he “fear” that the dam would overtop, but this belief and lack of fear was due to the
    releases made from the dam by the Bureau of Reclamation, because the water
    schedulers “were following the standard operating procedures.”
    At trial, Mr. VanShaar explained the Bureau’s unwillingness to let water enter the
    one-foot buffer as born out of concerns over uncertainty, stating: “We would not choose
    to use every last bit of storage space because nature could surprise us.” Mr. VanShaar
    stated that because the Bureau was receiving information regarding inflows to the dam
    and elevation, at most frequent, only every fifteen minutes, the water schedulers used the
    “buffer to absorb that uncertainty while we had a chance to then adjust for what we saw.”
    53
    Mr. Miller also testified to the reason the Bureau did not wait until the water in Lake
    Estes had reached an elevation of “7474 feet and a further release was indicated” before
    opening the radial gates beyond the amount that Gate 4 had been opened remotely:
    going up to 75 [7,475] is only like 100 acre-feet or 150 acre-feet in that
    storage space, so it wouldn’t have held hardly any of the water back. So the
    bigger concern was that if we got in a situation where we would start to
    overtop the gate -- so if we took it to 74 [7,474] and we got a sudden new
    influx of water from, you know, this rain event, it can very easily occupy that
    150 or 180, whatever, acre-feet of space that’s in that foot from 74 [7,474]
    to 75 [7,475].
    (alterations added). Mr. Miller further clarified that the Bureau “didn’t follow” the
    instructions in the Hazard Specific Guidelines to begin releases after reaching 7,474 feet
    in elevation, “because we didn’t want the elevation to get above 74 [7,474].” (alteration
    added). Moreover, Mr. Miller testified on cross-examination that he was unaware of any
    policies that would have prevented the Bureau from releasing water in emergency
    circumstances before water had reached an elevation of 7,474 feet in Lake Estes.
    Mr. VanShaar testified to the dangers of overtopping the radial gates of Olympus
    Dam:
    The dam is constructed in such a way with a spillway upon which the five
    radial gates sit. The normal operation for water to go over the spillway then
    is for us to open those gates and allow water through the created orifice
    under the gates, immediately on top of the spillway. It’s a smooth hydraulic
    transition. It allows the water to flow from a higher level of energy behind
    the dam, down along the spillway, to a lower level of energy in the river
    below. That's the way it’s intended.
    If water goes over the top of that, then there isn't that smooth hydraulic
    transition. It splashes down behind the gates, impacting the concrete
    spillway, subjecting it potentially to additional impact and abrasion and
    erosion, introducing a significant possibility for damage to the spillway.
    Compound that with the fact that on top of the reservoir is where much of
    the woody debris that comes along with flood waters collects, and you have
    the possibility of a log or some other piece of material flowing over the top
    and, again, impacting the concrete of the spillway, introducing the possibility
    of a crack or a break or a chip.
    Once that occurs on a spillway, the smooth surface introduces friction and
    turbulence that tends to erode further, and it worsens the condition and the
    chance for destruction of the spillway.
    Mr. VanShaar also indicated that the water schedulers believed that overtopping the
    gates would damage mechanical components “not intended to be submerged,” such as
    cables and stays.
    54
    At trial, Mr. Miller testified that the water schedulers considered the risk of
    overtopping the spillway gates to be “a bigger risk” than the size of the flows being
    released from the dam. In particular, Mr. Miller stated that the concern of the water
    schedulers was with regard to the unopened Gate 3:
    So the concern was that if it -- if it started to overtop that gate, it could start
    to tear it or something, and then, you know, problems, and then you have
    an open bay if it were able to tear the gate through the flow over top of it
    and possibly start to damage, you know, the dam to where there’s
    uncontrollable releases.
    Mr. Northrup testified, somewhat differently than Mr. VanShaar and Mr. Miller, “that there
    was no way to know if the gates would definitely fail,” “if the elevation level rises higher
    than the top of” the Olympus Dam spillway gates.
    The Post Incident Analysis Report prepared by the Bureau of Reclamation states
    under the heading “What Went Well,” with respect to the September 2013 flood:
    Dam Safety: Dam facilities performed well and experienced only minor
    damage. Paula Baty in the Area Office and other Dam Safety personnel in
    the Region and Denver offices were readily accessible and provided
    technical advice, as needed throughout and after the event. Estes area
    personnel were knowledgeable of dam monitoring requirements and
    procedures, and conscientiously monitored all three facilities involved. Dam
    operators from other facilities were cognizant of potential structural issues
    and were readily responsive in supporting onsite personnel.
    (capitalization and emphasis in original). The Post Incident Analysis Report further states
    in the section labeled “Section 5. Conclusion:”
    Had the dam operator not made it to the dam when he did, and CCC
    [Casper Control Center] had not maximized their remote operating
    capability of the radial gates, empirical routings suggest the radial gates
    would have overtopped at 4:27 a.m. and the dam would have likely
    overtopped at 9:30 a.m. on the morning of September 12th.
    (alteration added).
    Paula O’Brien differentiated in her testimony between “danger” and “risk” to
    Olympus Dam during the September 2013 flood. Specifically, Ms. O’Brien defined danger
    as “something that is an active present tense, something is happening that is -- that is a
    problem right then and there.” Ms. O’Brien stated her belief that the dam “certainly has
    risk” of overtopping “if there’s not a like response when we have high inflows.” Ms. O’Brien
    indicated in her testimony that, while “there’s long-term risk through the event” of a breach
    or overtopping of the dam, she did not believe that Olympus Dam was in danger at 7:52
    p.m. on September 12, 2013, when inflows to Lake Estes still exceeded outflows through
    Olympus Dam. Moreover, Ms. O’Brien continued to believe the dam was not in danger at
    approximately 1:14 a.m. on September 13, 2013, after the elevation of water in Lake
    55
    Estes began to reduce, although Ms. O’Brien maintained at that point that Olympus Dam
    was still “at risk.” Ms. O’Brien asserted in her testimony that Olympus Dam “remained
    safe and performing well throughout the incident,” although “[i]t was at varying degrees
    of risk throughout the event, varying degrees of overtopping risk throughout the event.”
    (alteration added). In particular, Ms. O’Brien stated she agreed with the sentiment,
    expressed by Kara Lamb in an email dated September 13 at 12:08 p.m., that “Olympus
    Dam is SAFE.” (capitalization in original).
    Ms. O’Brien testified that “[d]uring the September 2013 flood event,” the priority of
    the Olympus Dam Incident Management Team was “[p]ublic safety, and our role in that
    is preserving our high-risk structures, such as Olympus Dam.” (alterations added). Ms.
    O’Brien further testified that “if there were no releases” by the Bureau during the storm,
    “the Olympus Dam radial gates would have overtopped.” Ms. O’Brien elaborated:
    Gate failure can happen multiple ways. It could wind up where we wouldn’t
    be able to operate the gate, for example, if it were to -- for some reason
    those changes and forces caused that gate not to be able to operate to get
    -- it could fail entirely. If it were to fail entirely, there are a number of
    components that keep that gate in place and functioning, and any one of
    those could fail as a result of those forces changing both in the degree of
    those forces and increase in intensity over what they are normally and
    designed to be. So those are a few ways that that -- the gate could fail itself.
    And if that gate fails, you can also -- if it were to fail entirely away from the
    structure, then you have a release of over 5000 cfs right there that does not
    stop until you lower -- until it basically empties the reservoir and you don't
    have any control over those flows.
    Meanwhile, if the water were to come up high enough, then you wind up
    also having possible overtopping or the reserve flowing around other
    portions of the embankment where it's also not designed to withstand flows.
    At trial, Mr. VanShaar stated his belief that the September 2013 storm was
    “unprecedented” because “[w]e had not had a multi-day storm with continuous, relatively
    low precipitation rate that continued for that many days.” (alteration added). Mr. VanShaar
    further stated, with reference to the Senate Report on the C-BT Project admitted into
    evidence at trial, that the Bureau of Reclamation was “not operating the reservoir for
    purposes of preserving property downstream,” although Mr. VanShaar indicated that at
    some points “we delayed changes in our releases to afford first responders additional
    time to convey the need for evacuations in the Big Thompson Canyon.” According to the
    testimony of Mr. VanShaar, the operation of Olympus Dam did not deviate from the
    Standard Operating Procedures during the September 2013 storm.
    During his testimony, Mr. VanShaar calculated the time it would take to fill the one-
    foot buffer space above 7,474 feet of elevation in Lake Estes, based on the information
    in the Olympus Dam Standard Operating Procedures. The Standard Operating
    Procedures Provide that at a water level elevation of 7,474, Lake Estes stores 2,477.8
    56
    acre-feet of water, while at an elevation of 7,469.5, the bottom of the regulatory pool, Lake
    Estes holds 1,735.5 acre-feet. At the top of the buffer space, 7,475 feet in elevation, Lake
    Estes has a storage capacity of 2,659 acre-feet. Accordingly, Mr. VanShaar testified that
    a change in elevation of five-and-a-half feet, from 7,469.5 feet to 7,475 feet, amounts to
    an addition of 923.5 acre-feet of water to Lake Estes, while a change in elevation of one
    foot from 7,474 feet to 7,475 feet, amounts to an addition of 181.2 acre-feet of water.46
    Based on this information from the Standard Operating Procedures, Mr. VanShaar
    calculated that the one-foot buffer would be filled in two-and-one-quarter hours if the
    inflow to Lake Estes exceeded the outflow by 1,000 cfs.
    The parties stipulated that if Olympus Dam did not exist, the Olympus Tunnel
    would not exist either, and both the flow and debris held back by Olympus Dam and the
    flow and debris diverted into the Olympus Tunnel would have flowed down the Big
    Thompson River. At trial, Mr. VanShaar testified that, if the Olympus Dam were not
    present, the Bureau would not have been able to divert water away from flowing into the
    Big Thompson River, as it had through the Olympus Tunnel.
    The parties disputed at trial whether the damage which occurred to plaintiffs’
    properties was the result, in part, of flows from the North Fork Big Thompson River, which
    joins the Big Thompson River at Drake, Colorado, upstream of plaintiffs’ properties and
    which is not impacted by releases from Olympus Dam. At trial, Ms. O’Brien, who at the
    time of the September 2013 storm was a safety engineer at the East Colorado Area Office
    of the Bureau of Reclamation, testified that, at the time of the September 2013 flood event,
    she lived near Drake, “immediately upstream of the convergence,” in a neighborhood on
    the North Fork Big Thompson River, and therefore not far from the location of Ms. Orr’s
    property. Ms. O’Brien testified that during the storm, the bridge and roads near her home
    were damaged as a result of the North Fork Big Thompson River flooding, which caused
    the North Fork Big Thompson River to rise out of its banks and flow around the
    surrounding structures. Ms. O’Brien testified that she later learned through a National
    Resources Conservation Services report that flows in the North Fork Big Thompson River
    exceeded flows in the Big Thompson River during the September 2013 flood, in terms of
    cubic feet per second flow, although Ms. O’Brien clarified that she did not learn that until
    after the fact. Ms. O’Brien also testified to the degree to which floodwaters carried
    sediment and debris, and whether that would have added to the volume of flows. Ms.
    O’Brien testified that while she was unaware of “specific reports of sediment,” she
    “recall[ed] having issues with sedimentation being deposited” by the floodwaters in the
    facilities generally, and stated that she “would assume it” because “that kind of rainfall
    event, you are going to have sedimentation problems.” (alteration added). Ms. O’Brien
    further stated that when “the soil was saturated at that point after several days of rain,
    and when you have high-intensity rainfall or even low-intensity rainfall on saturated soil,
    46 The Standard Operating Procedures for Olympus Dam state at one point that a change
    in water elevation from 7,474 feet to 7,475 feet would amount to an increase of 182 acre-
    feet of storage. At another point, however, the Standard Operating Procedures provide
    the “active capacity” of the Lake Estes reservoir at each tenth of a foot in elevation, giving
    the storage at 7,474 feet as 2,477.8 acre-feet, and the storage at 7,475 feet as 2,659
    acre-feet, a difference of 181.2 acre-feet.
    57
    it washes off the dirt, and the dirt goes downstream, which then goes into your reservoirs,”
    and Ms. O’Brien testified that “we did have significant sedimentation in Lake Estes” during
    the September 2013 storm.
    The evidence in the record before the court includes an August 2014 report titled,
    “Hydrologic Evaluation of the Big Thompson Watershed” for the September 2013 flood,
    which states that it was prepared for the Colorado Department of Transportation by
    Jacobs Engineering Group. (the Colorado Department of Transportation 2014 Hydrology
    Report). The Colorado Department of Transportation 2014 Hydrology Report states that
    it contains analyses performed after the September 2013 storm, and that
    [t]he purpose of the analyses is to ascertain the approximate magnitude of
    the September flood event in key locations throughout the watersheds and
    to prepare estimates of peak discharge that can serve to guide the design
    of permanent roadway and other infrastructure improvements along the
    impacted streams. These estimates of peak discharges for various return
    periods will be shared with local floodplain administrators for their
    consideration in revising or updating any current regulatory discharges.
    (alteration added). The Colorado Department of Transportation 2014 Hydrology Report
    also states that “[p]rior to September 2013, the last major flooding event on the Big
    Thompson River upstream of Loveland was the infamous 1976 Big Thompson Flood.”
    (alteration added).
    The Colorado Department of Transportation 2014 Hydrology Report indicates that,
    in December 2013, “[e]stimates of peak discharges associated with the September flood
    event based on field observations were undertaken by Bob Jarrett of Applied Weather
    Associates,” and states that “[t]he discharge estimates provided by Bob Jarrett, as well
    as any other available discharge estimates in the watersheds, were compared to the
    current regulatory discharges to provide an initial assessment of the relative magnitude
    of the September floods.” (alterations added). The discharge estimates developed by Bob
    Jarrett are also set forth in the appendices of the Colorado Department of Transportation
    2014 Hydrology Report in a memorandum dated January 21, 2014, and revised July 16,
    2014, which has the subject “CDOT/CWCB Hydrology Investigation Phase One – 2013
    Flood Peak Flow Determinations.” (the Phase One Memorandum). (capitalization and
    emphasis in original). Further, the Colorado Department of Transportation 2014
    Hydrology Report includes the results of Jacobs Engineering Group’s hydrologic model
    compared with the calculations by Bob Jarrett with respect to the September 2013 flood:
    the peak discharge from Olympus Dam during the September 2013 storm was calculated
    to be 5,327 cfs by both Jacobs Engineering Group and by Bob Jarrett. Peak flow at the
    confluence at Drake was calculated to be between 14,728 and 14,731 cfs by Jacobs
    Engineering Group, compared with 14,800 cfs by Bob Jarrett. The North Fork Big
    Thompson River peak flow at Drake was calculated to be between 7,706 and 7,723 cfs
    by Jacobs Engineering Group, compared with 5,900 cfs by Bob Jarrett. Peak flow in the
    Big Thompson River above Drake was calculated to be between 7,534 and 7,566 cfs by
    Jacobs Engineering Group, compared with 12,500 cfs by Bob Jarrett. The Colorado
    Department of Transportation 2014 Hydrology Report explained why the Jacobs
    58
    Engineering Group’s calculated peaks did not match the Jarrett calculations by Bob
    Jarrett:
    Downstream of Lake Estes, the calibrated model did not match the higher
    peak discharge estimates provided by Bob Jarrett (6,300cfs vs. 9,300 cfs at
    Loveland Heights and 7,600 cfs vs. 12,500 cfs at Mountain Shadows Lane).
    The primary reason the model did not match these peak discharges was
    because the model calibration in this reach was more heavily weighted to
    reflect the reliable Lake Estes discharge hydrograph. The relatively limited
    drainage area contributing runoff downstream of Lake Estes was insufficient
    to increase the peak discharges from the reservoir enough to match the
    other two estimates. However, further downstream, below the confluence
    with the North Fork Big Thompson at Drake, the calibrated model was able
    to match Bob Jarrett’s estimate of 14,800 cfs within 1 percent.
    DISCUSSION
    Plaintiffs argue that the defendant’s actions by employees of the Bureau of
    Reclamation during the September 2013 flood resulted in a taking of plaintiffs’ properties
    by the defendant pursuant to the Fifth Amendment to the Constitution. The Takings
    Clause of the Fifth Amendment to the United States Constitution provides in pertinent
    part: “nor shall private property be taken for public use without just compensation.” U.S.
    Const. amend. V. The purpose of this Fifth Amendment provision is to prevent the
    government from “‘forcing some people alone to bear public burdens which, in all fairness
    and justice, should be borne by the public as a whole.’” Ark. Game & Fish Comm'n v.
    United States, 
    568 U.S. 23
    , 31 (2012) (quoting Armstrong v. United States, 
    364 U.S. 40
    ,
    49 (1960)); see also Palazzolo v. Rhode Island, 
    533 U.S. 606
    , 618 (2001) (quoting
    Armstrong v. United States, 
    364 U.S. at 49
    ), abrogated on other grounds by Lingle v.
    Chevron U.S.A. Inc., 
    544 U.S. 528
     (2005)); Penn Cent. Transp. Co. v. City of New York,
    
    438 U.S. 104
    , 123-24 (1978); Lingle v. Chevron U.S.A. Inc., 
    544 U.S. at 536
    ; E. Enters.
    v. Apfel, 
    524 U.S. 498
    , 522 (1998); Pumpelly v. Green Bay & Miss. Canal Co., 
    80 U.S. (13 Wall.) 166
    , 179 (1871) (citing principles which establish that “private property may be
    taken for public uses when public necessity or utility requires” and that there is a “clear
    principle of natural equity that the individual whose property is thus sacrificed must be
    indemnified”); Reoforce, Inc. v. United States, 
    853 F.3d 1249
    , 1265 (Fed. Cir.), cert.
    denied, 
    138 S. Ct. 517 (2017)
    ; Rose Acre Farm, Inc. v. United States, 
    559 F.3d 1260
    ,
    1266 (Fed. Cir. 2009); Janowsky v. United States, 
    133 F.3d 888
    , 892 (Fed. Cir. 1998).
    To succeed under the Fifth Amendment Takings Clause, a plaintiff has the burden
    of proof to demonstrate that the government took a private property interest for public use
    without just compensation. See St. Bernard Par. Gov’t v. United States, 
    887 F.3d 1354
    ,
    1362 (Fed. Cir. 2018) (“It is well established that a takings plaintiff bears the burden of
    proof to establish that the government action caused the injury.”); Dimare Fresh, Inc. v.
    United States, 
    808 F.3d 1301
    , 1306 (Fed. Cir. 2015) (stating that the “‘classic taking’” is
    one in which the government directly appropriates private property for its own use
    (quoting Tahoe-Sierra Pres. Council, Inc. v. Tahoe Reg’l Planning Agency, 
    535 U.S. 302
    ,
    324 (2002))), cert. denied, 
    579 U.S. 902
     (2016); Adams v. United States, 
    391 F.3d 1212
    ,
    59
    1218 (Fed. Cir. 2004), cert. denied, 
    546 U.S. 811
     (2005); Arbelaez v. United States, 
    94 Fed. Cl. 753
    , 762 (2010). The government must be operating in its sovereign rather than
    in its proprietary capacity when it initiates a taking. See St. Christopher Assocs., L.P. v.
    United States, 
    511 F.3d 1376
    , 1385 (Fed. Cir. 2008).
    The United States Court of Appeals for the Federal Circuit has established a two-
    part test to determine whether government actions amount to a taking of private property
    under the Fifth Amendment. See Casitas Mun. Water Dist. v. United States, 
    708 F.3d 1340
    , 1348 (Fed. Cir. 2013); Klamath Irr. Dist. v. United States, 
    635 F.3d 505
    , 511 (Fed.
    Cir. 2011); Am. Pelagic Fishing Co., L.P. v. United States, 
    379 F.3d 1363
    , 1372 (Fed.
    Cir.) (citing M & J Coal Co. v. United States, 
    47 F.3d 1148
    , 1153-54 (Fed. Cir.), cert.
    denied, 
    516 U.S. 808
     (1995)) reh’g en banc denied (Fed. Cir. 2004), cert. denied, 
    545 U.S. 1139
     (2005). A court first determines whether a plaintiff possesses a cognizable
    property interest in the subject of the alleged taking. See Loretto v. Teleprompter
    Manhattan CATV Corp., 
    458 U.S. 419
    , 435 (1982) (citing United States v. Gen. Motors
    Corp., 
    323 U.S. 373
     (1945)); see also McCutchen v. United States, 
    14 F.4th 1355
    , 1364
    (Fed. Cir. 2021) (quoting Huntleigh USA Corp. v. United States, 
    525 F.3d 1370
    , 1377
    (Fed. Cir.), cert. denied, (2008)); Welty v. United States, 
    926 F.3d 1319
    , 1323-24 (Fed.
    Cir. 2019) (“To maintain a cognizable claim for a Fifth Amendment taking, a plaintiff must
    establish that he possessed an enforceable property right.” (citing Lucas v. S.C. Coastal
    Council, 
    505 U.S. 1003
    , 1014-19 (1992))); Am. Pelagic Fishing Co., L.P. v. United States,
    
    379 F.3d at 1372
     (“‘It is axiomatic that only persons with a valid property interest at the
    time of the taking are entitled to compensation.’” (quoting Wyatt v. United States, 
    271 F.3d 1090
    , 1096 (Fed. Cir. 2001), cert. denied, 
    535 U.S. 1077
     (2002); and citing Cavin v.
    United States, 
    956 F.2d 1131
    , 1134 (Fed. Cir. 1992))); Air Pegasus of D.C., Inc. v. United
    States, 
    424 F.3d 1206
    , 1213 (Fed. Cir.) (stating that the court does not address the
    second step “without first identifying a cognizable property interest” (citing Am. Pelagic
    Fishing Co., L.P. v. United States, 
    379 F.3d at 1381
    ; and Conti v. United States, 
    291 F.3d 1334
    , 1340 (Fed. Cir. 2002))), reh’g denied and reh’g en banc denied (Fed. Cir. 2005);
    Karuk Tribe of Cal. v. Ammon, 
    209 F.3d 1366
    , 1374-75 (Fed. Cir.), reh’g denied and en
    banc suggestion denied (Fed. Cir. 2000), cert. denied, 
    532 U.S. 941
     (2001). “If the
    claimant fails to demonstrate the existence of a legally cognizable property interest, the
    courts [sic] task is at an end.” Am. Pelagic Fishing Co., L.P. v. United States, 
    379 F.3d at
    1372 (citing Maritrans Inc. v. United States, 
    342 F.3d 1344
    , 1352 (Fed. Cir. 2003); and M
    & J Coal Co. v. United States, 
    47 F.3d at 1154
    ); see also Hearts Bluff Game Ranch, Inc.
    v. United States, 
    669 F.3d 1326
    , 1329 (Fed. Cir.) (citing Am. Pelagic Fishing Co., L.P. v.
    United States, 
    379 F.3d at 1372
    ), cert. denied, 
    567 U.S. 917
     (2012).
    In addition to “‘having identified a valid property interest, the court must determine
    whether the governmental action at issue amounted to a compensable taking of that
    property interest.’” Huntleigh USA Corp. v. United States, 
    525 F.3d at 1378
     (quoting Am.
    Pelagic Fishing Co., L.P. v. United States, 
    379 F.3d at 1372
    ). In Arkansas Game & Fish
    Commission v. United States, the United States Supreme Court recognized five criteria
    relevant to analyzing whether government-induced flooding results in a compensable
    taking of a property interest. See Ark. Game & Fish Comm’n v. United States, 
    568 U.S. at 38-39
    . A Judge of the United States Court of Federal Claims summarized the Arkansas
    Game & Fish Commission criteria as a five-factor test that examines:
    60
    (1) time—the duration of the physical invasion; (2) causation; (3) intent or
    foreseeability, that is, “the degree to which the invasion is intended or is the
    foreseeable result of authorized government action;” (4) “the owner’s
    reasonable investment-backed expectations regarding the land’s use,”
    including “the character of the land;” and (5) the “[s]everity of the
    interference.”
    In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 
    138 Fed. Cl. 658
    ,
    665 (2018) (quoting Ark. Game & Fish Comm'n v. United States, 
    568 U.S. at 38-39
    ; and
    citing Ark. Game & Fish Comm'n v. United States, 
    736 F.3d 1364
    , 1369-75 (Fed. Cir.
    2013)); see also Milton v. United States, 
    36 F.4th 1154
    , 1163 (Fed. Cir. 2022); St. Bernard
    Par. Gov’t v. United States, 
    887 F.3d at 1362
    ; In re Upstream Addicks & Barker (Texas)
    Flood-Control Reservoirs, 
    146 Fed. Cl. 219
    , 249 (2019). With respect to causation, in
    cases where plaintiffs claim that flooding of their land is caused by the government’s
    operation of a dam, the Federal Circuit has explained that plaintiffs must show that the
    government’s “‘construction or operation of the [dam] subjected their lands to any
    additional flooding above what would have occurred in consequence of the severe . . .
    storm had defendant not constructed the [dam] at all.’” St. Bernard Par. Gov’t v. United
    States, 
    887 F.3d at 1363
     (alterations and ellipsis in original) (quoting Accardi v. United
    States, 
    220 Ct. Cl. 347
    , 358, 
    599 F.2d 423
    , 430 (1979)). In other words, “the causation
    analysis requires the plaintiff to establish what damage would have occurred without
    government action.” 
    Id.
    As jointly stipulated to by the parties, at the time of the September 2013 flood, Ms.
    Orr as well as Mr. and Mrs. Carman “owned property downstream of Olympus Dam, on
    the Big Thompson River in the Big Thompson River Canyon.” At issue in this Opinion is
    whether plaintiffs can demonstrate that the government’s operation of Olympus Dam
    during certain days in September 2013 caused a taking of plaintiffs’ properties when their
    properties were flooded. The United States Court of Appeals for the Federal Circuit in
    Ridge Line, Inc. v. United States, 
    346 F.3d 1346
     (Fed. Cir. 2003), explained, in order to
    prevail on a claim for a taking by inverse condemnation, plaintiffs in this case “must
    establish that treatment under takings law, as opposed to tort law, is appropriate under
    the circumstances.”47 Ridge Line, Inc. v. United States, 
    346 F.3d at 1355
    . The United
    47 Throughout the above captioned case, plaintiffs have inconsistently characterized the
    nature of their takings claims. In their complaint, plaintiffs alleged that “Defendant’s
    actions constituted a taking of property or inverse condemnation,” and that plaintiffs’
    “damages included the loss of the use, occupancy, and enjoyment of the Plaintiffs’ homes
    and properties and the displacement or permanent removal or alteration of the Plaintiffs’
    real property.” In their opening statement at trial, plaintiffs argued that government-
    induced flooding “resulted in the permanent taking of the property under their homes and
    businesses, and as a result, we believe that compensation is proper, proper [sic] under
    the takings law.” (alteration added). In their post-trail brief, however, plaintiffs argue,
    quoting In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl.
    at 247 n.17, that plaintiffs
    61
    States Supreme Court, in Cedar Point Nursery v. Hassid, 
    141 S. Ct. 2063
    , addressed
    different forms of physical takings, stating in relevant part that “the government likewise
    effects a physical taking when it occupies property—say, by recurring flooding as a result
    of building a dam.” 
    Id.
     at 2071 (citing United States v. Cress, 
    243 U.S. 316
    , 327-38
    (1917)). The Supreme Court in Cedar Point Nursery further stated, “we have held that a
    physical appropriation is a taking whether it is permanent or temporary.” Id. at 2074. The
    Supreme Court explained that “our holding does nothing to efface the distinction between
    trespass and takings. Isolated physical invasion, not undertaken pursuant to a granted
    right of access, are properly assessed as individual torts rather than appropriations of a
    property right. This basic distinction is firmly grounded in our precedent.” Id. at 2078 (citing
    “have alleged three separate takings: (1) a temporary, categorical, physical
    taking for the temporary flooding; (2) a permanent, categorical, physical
    taking for the destruction of plaintiffs’ personal property; and (3) a
    permanent, non-categorical, physical taking for the flowage easements on
    each property” resulting from the erosion of the riverbanks of the Orr and
    Carman properties and continued flow of the Big Thompson River over what
    was once property above the riverbanks.
    At the closing argument, plaintiffs stated a different basis for their claims, that “the nature
    of the invasion was a permanent washing away of property. This was not a temporary
    taking or regulatory taking, but it is a physical taking.” While plaintiffs have articulated the
    nature of their alleged taking in multiple, inconsistent and mutually exclusive ways, their
    arguments in their briefs and before this court have reflected and concentrated on an
    application of the Supreme Court’s framework set forth in Arkansas Game & Fish
    Commission. As the Supreme Court explained in Cedar Point Nursery v. Hassid, the
    Arkansas Game & Fish Commission test is applicable in the context of temporary flood-
    induced takings. See Cedar Point Nursery v. Hassid, 
    141 S. Ct. 2063
    , 2079 (2021) (“Our
    approach in Arkansas Game and Fish Commission reflects nothing more than an
    application of the traditional trespass-versus-takings distinction to the unique
    considerations that accompany temporary flooding.”). Plaintiffs have not argued the
    application of the standards of permanent, physical takings to their claims in this court.
    See, e.g., Cedar Point Nursery v. Hassid, 141 S. Ct. at 2073 (“[W]e made clear that a
    permanent physical occupation constitutes a per se taking regardless whether it results
    in only a trivial economic loss.” (alteration added) (citing Loretto v. Teleprompter
    Manhattan CATV Corp., 
    458 U.S. at 423
    )); 
    id.
     (“We reiterated that the appropriation of an
    easement constitutes a physical taking in Nollan v. California Coastal Commission.”
    (citing Nollan v. Cal. Coastal Comm’n, 
    483 U.S. 825
    , 828 (1987))); id. at 2075 (“The
    upshot of this line of precedent is that government-authorized invasions of property—
    whether done by plane, boat, cable, or beachcomber—are physical takings requiring just
    compensation.”). Because plaintiffs have argued their takings claims within the Arkansas
    Game & Fish Commission temporary, flood-induced takings analysis, and not under the
    permanent, physical takings analysis, and based on the evidence produced at trial, the
    court considers plaintiffs’ claims as for temporary, flood-induced takings of the Orr and
    Carman properties.
    62
    Portsmouth Harbor Land & Hotel Co. v. United States, 
    260 U.S. 327
    , 329-30 (1922)).
    Moreover, the Supreme Court explained:
    The distinction between trespass and takings accounts for our treatment of
    temporary government-induced flooding in Arkansas Game and Fish
    Commission v. United States, 
    568 U.S. 23
    , 
    133 S. Ct. 511
    , 
    184 L. Ed. 2d 417
     (2012). There we held, “simply and only” that such flooding “gains no
    automatic exemption from Takings Clause inspection.” 
    Id., at 38
    , 
    133 S. Ct. 511
    . Because this type of flooding can present complex questions of
    causation, we instructed lower courts evaluating takings claims based on
    temporary flooding to consider a range of factors including the duration of
    the invasion, the degree to which it was intended or foreseeable, and the
    character of the land at issue. 
    Id., at 38-39
    , 
    133 S. Ct. 511
    . Applying those
    factors on remand, the Federal Circuit concluded that the government had
    effected a taking in the form of a temporary flowage easement. Arkansas
    Game and Fish Comm’n v. United States, 
    736 F.3d 1364
    , 1372 (2013). Our
    approach in Arkansas Game and Fish Commission reflects nothing more
    than an application of the traditional trespass-versus-takings distinction to
    the unique considerations that accompany temporary flooding.
    Cedar Point Nursery v. Hassid, 141 S. Ct. at 2078-79. Based on the Supreme Court’s
    analysis in Cedar Point Nursery, an application of the Arkansas Game & Fish Commission
    factors to the above captioned case determines whether plaintiffs’ claims for just
    compensation based on the flooding of their properties sound in tort or in takings.
    Causation
    Plaintiffs, Ms. Orr and Mr. and Mrs. Carman, acknowledging plaintiffs’ burden to
    prove a taking, cite to the Federal Circuit’s decision in St. Bernard Parish Government v.
    United States, 
    887 F.3d 1354
    , to argue that “Plaintiffs must show that, ‘in the ordinary
    course of events, absent government action, plaintiffs would not have suffered the injury.’”
    (quoting St. Bernard Par. Gov’t v. United States, 
    887 F.3d at 1362
    ). Plaintiffs refer to the
    instruction in St. Bernard Parish, that “with respect to flooding during severe storms in
    cases involving a dam, a plaintiff must demonstrate that he or she suffered ‘additional
    flooding above what would have occurred in consequence of the severe . . . storm had
    defendant not constructed the [dam] at all.’” (alteration and ellipsis in original) (quoting St.
    Bernard Par. Gov’t v. United States, 
    887 F.3d at 1363
     (internal quotations omitted)).
    Plaintiffs acknowledge that the “totality of the government’s actions” must be considered,”
    including actions by the government “that might have mitigated” damage to plaintiffs’
    properties. (citing St. Bernard Par. Gov’t v. United States, 
    887 F.3d at 1364, 1367
    ).
    Plaintiffs, nevertheless, assert that the damage to, and loss of use of, Ms. Orr’s and the
    Carmans’ properties “more probably than not resulted from the Bureau’s decisions and
    actions to protect its facilities during the 2013 storm event, its storage of water of
    September 12, and its releases of storage flows from the Olympus Dam during the night
    and early morning of September 12-13, 2013.”
    63
    Defendant, however, argues that “it did not cause the flooding and erosion of
    Plaintiffs’ properties,” and that the United States is entitled to judgment in its favor.
    Defendant relies on the same standards cited by plaintiffs from the same St. Bernard
    Parish decision of the Federal Circuit, and argues that “[t]o demonstrate causation a
    plaintiff must show what would have happened if the government had not acted,”
    (alteration added), in particular, “Plaintiffs must show that they suffered ‘additional
    flooding above what would have occurred in consequence of the severe . . . storm had
    defendant not constructed the [dam] at all.’” (alteration and ellipsis in original) (quoting St.
    Bernard Par. Gov’t v. United States, 
    887 F.3d at 1363
     (internal quotations omitted)).
    In addition to the fact witnesses who appeared at trial, plaintiffs offered the
    testimony of two experts, Mr. L. Clint Brown and Mr. Noel Potter, while defendant also
    offered the testimony of two experts, Dr. George F. McMahon and Dr. David S. Bowles.
    Plaintiffs’ firs expert, Mr. Brown, was accepted by the court as an expert in the fields of
    hydrology, hydraulics, dam safety, and dam and reservoir operations. Plaintiffs’ second
    expert, Mr. Potter, was accepted by the court as an expert in the field of land surveying.
    Defendant’s first expert, Dr. McMahon, was accepted by the court as an expert in the
    fields of hydraulics, hydrology, and dam reservoir operations. Defendant’s second expert,
    Dr. Bowles, was accepted by the court as an expert in the fields of flood hydrology,
    reservoir operations, and dam safety.
    Plaintiffs’ expert Mr. Brown prepared an “Engineer’s Opinion Report,” dated
    January 2021, and a revised version in February 2021. (capitalization and emphasis in
    original). Mr. Brown testified that the data he relied on to produce his opinion was provided
    by the Bureau of Reclamation. Mr. Brown’s expert report indicates that Mr. Brown’s firm,
    Engineering Analytics, Inc.,48 was “retained by Burg Simpson [plaintiffs’ counsel] to
    evaluate how operations of Olympus Dam may have contributed to the damage” at
    plaintiffs’ properties. (alteration added). According to his expert report, Mr. Brown relied
    on data from the Bureau of Reclamation regarding Olympus Dam water releases, which
    data was identified as the “‘revised release’ dataset” by Mr. Brown. (emphasis in original).
    Mr. Brown performed a hydraulic analysis, which according to his expert report “consists
    of a water balance for Olympus Dam/Lake Estes and a hydraulic model of the Big
    Thompson River with a focus on the three properties.” Mr. Brown listed “general
    assumptions” of the hydraulic analysis, including “[b]ulking factors of the flow” which
    “varied between 1.1 and 2.0.” (alteration added). His expert report states: “The
    observed/estimated peak flows accounted for bulking, but the flows released from
    Olympus did not account for bulking that would occur just downstream.” With the Olympus
    Dam release data and the assumptions, Mr. Brown’s expert report indicates that Mr.
    Brown conducted “water balance calculations,” explained as follows:
    The Olympus Dam water balance accounts for inflows, outflows, and
    changes in storage in Lake Estes. The purpose of the water balance was to
    48Mr. Brown identified himself in his expert report as “a Civil/Geotechnical Engineer,” and
    stated that he is “currently the Senior Dam and Reservoir Engineer, and a Vice President
    at Engineering Analytics, Inc., a consulting engineering company in Fort Collins,
    Colorado.”
    64
    determine: 1) how much flow was released from Olympus Dam into the Big
    Thompson River and 2) if releases into the Big Thompson River were
    greater than inflows.
    Mr. Brown relied on the estimates of the peak flows during the September 2013 storm set
    forth in the “Phase One Memorandum,” calculated by Bob Jarrett, which was included
    with the Colorado Department of Transportation 2014 Hydrology Report prepared by the
    Jacobs Engineering Group, rather than the Colorado Department of Transportation 2014
    Hydrology Report. The peak flows used by Mr. Brown were 5,900 cfs in the North Fork
    Big Thompson River at Drake, 12,500 cfs in the Big Thompson River at Drake, 14,800
    cfs below Drake and after the confluence with the North Fork Big Thompson River, and
    15,500 cfs further downstream, below the mouth of the Big Thompson River Canyon. Of
    these estimated peak flows, Mr. Brown estimated the 14,800 cfs flow of the Big Thompson
    River below Drake to be the peak flow at plaintiffs’ properties, because plaintiffs’
    properties were no more than approximately two and a half miles downstream of Drake,
    and “[l]ittle to no attenuation of the peak flow of 14,800 cfs is anticipated between the Big
    Thompson below Drake location and the damaged properties.” (alteration added).
    Mr. Brown also addressed in his expert report the impact of “bulking” on the water
    released from Olympus Dam, which he explained as the tendency that “the water will pick
    up sediment, boulders, trees and other debris. The additional volume of sediment,
    boulders, trees, and other debris will result in increased volume in flow.” In his expert
    report, Mr. Brown indicated that the peak flows he used from the Phase One
    Memorandum of the Colorado Department of Transportation 2014 Hydrology Report
    “already include the bulking factor” because “by the time the water released from the dam
    traveled to the properties in question the released flows had picked up sediment and
    debris in the canyon.” In the results of his hydraulic analysis, Mr. Brown stated that peak
    release from Olympus Dam occurred at 11:45 p.m., September 12, 2013, at which time
    a rate of 5,377 cfs was released into the Big Thompson River. Mr. Brown further
    determined “that the flows released from Olympus Dam into the Big Thompson River
    arrived at the properties between 1.2 and 2.0 hours after release,” such that “Olympus
    Dam’s peak ‘revised release’ of 5377 cfs at 23:45 on September 12 would have reached
    the properties between approximately 1:00 and 1:45 on September 13.” (emphasis in
    original).
    Mr. Brown calculated that 722 cfs of stored water was released into the Big
    Thompson River during the peak release from Olympus Dam, and Mr. Brown termed this
    portion of the peak flow “storage flow.” Mr. Brown applied three bulking factors, 1.1, 1.6,
    and 2.0,49 to this 722 cfs storage flow figure, producing “bulked storage flows” of 794,
    1,155, and 1,444 cfs, respectively. Mr. Brown subtracted from the peak flow of 14,800 cfs
    at plaintiffs’ properties, which produced “theoretical peak flows” of 14,006, 13,645, and
    49 Mr. Brown explained in his expert report that “[b]ulking has been found to range
    between 1.1 and 1.6 for the rivers that were studied by WEST Consultants, Inc.,” and that
    “Gusman et al. (2009) summarize a variety of California county bulking factor guidelines
    or requirements, where counties suggest a bulking factor as high as 2.0 for design.”
    (alteration added).
    65
    13,356 cfs, respectively, each of which Mr. Brown explained “represents the estimated
    peak flow at the properties if the Olympus Dam had released outflows in the Big
    Thompson River that were equal to watershed inflows.” Mr. Brown’s expert report further
    indicates that Mr. Brown employed an “HEC-RAS [Hydrologic Engineering Center-River
    Analysis System] mode” in order “to determine the depths of flow at cross-sections that
    represent the three damaged properties” and to “determine the increase in the depth, due
    to storage releases of Olympus Dam.” (alteration added). Mr. Brown calculated that at the
    Orr property, “[t]he difference in depth between the actual peak flow depth and the
    theoretical peak flow depth ranges from 0.24 to 0.54 feet,” that at the northern portion of
    the Carman property, the difference in depth “range [sic] from 0.27 to 0.52 feet,” and that
    at the southern portion of the Carman property, the difference in depth “ranges from 0.30
    to 0.55 feet,” with higher bulking factors producing a greater difference in depth at each
    property. (alterations added). Mr. Brown explained in his expert report:
    Increases in flood depth result in an increased pore pressure of the
    foundation soils, decreased soil stability, and increased erosion potential.
    As the depth of water increases, water pressures decrease the effective
    stress in the soil particles. As effective stress in the soil particles decrease,
    the soil becomes less stable and more susceptible to erosion. The increase
    in erosive potential due to increases in flow depth more probably than not
    resulted in increased damage and loss of land at the three properties. The
    resulting decreases in effective stress in the foundation soils beneath the
    properties more probably than not contributed to foundation movement and
    potential loss of structure.
    Following the hydraulic analysis, Mr. Brown offered “conclusions and opinions,” including
    that “Storage Flow releases into the Big Thompson River exceeded the expected river
    flows by as much as 722 cfs during the estimated time that the houses were initially
    damaged and by as much as 868 cfs during the event.” (capitalization in original). Mr.
    Brown also concluded:
    The storage releases from Olympus Dam were lower than flows from the
    Big Thompson River and North Fork of the Big Thomson River watershed.
    Additionally, Lake Estes storage releases into the Big Thompson River
    would not by themselves cause flooding of the properties. Moreover, due to
    the extreme nature of the 2013 event flooding of the properties may have
    occurred, however the timing (starting at the peak of flows) and duration
    (18.5 hours) more probably than not that the Lake Estes storage releases
    would have been “the straw that broke the camel’s back.”
    As noted above, plaintiffs’ second expert witness was Mr. Noel Potter, who testified
    that he is a land surveyor and “president of CCS Consultants, Incorporated, a surveying
    firm.” Mr. Potter prepared graphics representing Ms. Orr’s property before and after the
    September 2013 flood, which graphics were admitted at trial as evidence without
    objection. Mr. Potter testified that he did not visit Ms. Orr’s property to make the graphics,
    but rather used “an image from Google Earth,” dated 2012, for the pre-2013 flood image.
    A document titled, “EXPLANATION OF ELIZABETH ORR FLOOD GRAPHICS,”
    66
    prepared by Mr. Potter and admitted as an exhibit in the record, indicates that an image
    of Google Earth, dated 2019, also was used for the post-2013 flood image. (capitalization
    and emphasis in original). Mr. Potter testified that he superimposed the lines of Ms. Orr’s
    property on the images based on the plat of the subdivision in which Ms. Orr’s property
    is located. Mr. Potter also testified that he estimated the shoreline of the Big Thompson
    River with respect to Ms. Orr’s property and marked the centerline of the river, which
    formed one boundary of Ms. Orr’s property. On the graphic depicting Ms. Orr’s property
    before the September 2013 flood, Mr. Potter imposed text which reads: “PRE 2013
    FLOOD APPROXIMATELY 0.14 ACRES IN THE RIVER.” (capitalization in original). On
    the graphic depicting Ms. Orr’s property after the September 2013 flood, Mr. Potter
    imposed text which reads: “POST 2013 FLOOD APPROXIMATELY 0.77 ACRES IN THE
    RIVER AREA.” (capitalization in original). At the bottom of both Mr. Potter’s pre- and post-
    September 2013 flood graphics, Mr. Potter included, “NOTE: THIS EXHIBIT DOES NOT
    REPRESENT A MONUMENTED LAND SURVEY. IT IS INTENDED ONLY AS A
    GRAPHIC DEPICITION OF THE ATTACHED DESCRIPTION,” (capitalization in original),
    and Mr. Potter explained at trial: “That’s included because I did not perform any field
    survey to prepare this graphic.” Mr. Potter testified that it was his “opinion that these
    graphics represent, to a reasonable degree of certainty, the pre- and post-flood acreage
    of Ms. Libby Orr’s property.” Mr. Potter did not produce a similar graphic of the Carmans’
    property before and after the September 2013 flood, and plaintiffs did not provide a
    separate expert to analyze the Carman property.
    Defendant’s first expert witness was Dr. George McMahon, who testified that he
    holds a Ph.D. “in water and environmental engineering and with a minor in economics
    and public policy.” Dr. McMahon testified that he works for Arcadis U.S., Inc., as a vice
    president and as a national expert in water management, which Dr. McMahon testified
    “means I basically get involved in projects all over the world providing technical support,
    technical oversight, quality assurance, quality control, and also business development in
    these areas.” Dr. McMahon prepared an expert report for defendant, titled “Analysis of
    the Big Thompson River Flood of September 2013,” dated January 2021. Dr. McMahon’s
    expert report states that Dr. McMahon sought to determine “the extent to which Olympus
    Dam releases during the September 2013 flood may have contributed to flooding of the
    Orr and Carman (Plaintiffs) properties.” Dr. McMahon’s expert report explains that
    “[d]etermination of river stages and flow velocities attributable to spillway releases
    required comparison of actual spillway releases (regulated flow scenario) with alternative
    flow scenarios.” Dr. McMahon considered two alternatives, “‘[p]erfect’ reservoir operation,
    with spillway releases exactly equal to net Olympus reservoir inflows after accounting for
    Adams Tunnel inflows to and Olympus Tunnel diversions from the reservoir (unregulated
    flow scenario),” and “[n]atural flow at the site of Olympus Dam assuming the dam,
    reservoir, Adams Tunnel, and Olympus Tunnel did not exist (unimpaired flow scenario).”
    (alterations added).
    According to his expert report, Dr. McMahon’s methodology was to “[v]erify” the
    Bureau of Reclamation’s “Olympus Dam inflow and outflow calculations during the event;”
    to “[d]erive unimpaired (naturalized) inflows at Olympus dam site,” to “[d]evelop a
    simplified HEC-HMS (Hydrologic Modeling System) model” to estimate “flood
    hydrographs at Plaintiffs’ properties based on rainfall-runoff simulation, combining and
    67
    routing of Olympus Dam flows to the Carman (the most downstream) property,” and to
    “[d]evelop a steady-flow HEC-RAS (River Analysis System) model” to compare “peak
    flood stages and flow velocities at Plaintiffs’ properties computed based on Colorado
    Department of Transportation (CDOT) and Arcadis hydrologic model results.” (alterations
    added). Dr. McMahon determined peak flow to occur at the Olympus Dam location at
    11:45 p.m., September 12, 2013, for all three scenarios, the actual “regulated flow”
    scenario and the hypothetical “unregulated flow” and “unimpaired flow” scenarios. Dr.
    McMahon calculated the peak flow of each scenario: 5,283 cfs for regulated flow, 5,173
    cfs for unregulated flow, and 5,385 cfs for unimpaired flow. Dr. McMahon further
    calculated the peak flow of the North Fork Big Thompson River, 7,777 cfs at 1:00 a.m.,
    September 13, 2013, and from these calculations, he determined the time and rate of
    peak flow at plaintiffs’ properties under each of the three scenarios.
    Dr. McMahon calculated peak flow to have occurred at 12:45 a.m., September 13,
    at the Orr property, at a rate of 15,011 cfs under the regulated flow, 14,943 cfs under
    unregulated flow, and 15,108 under the unimpaired flow. At the Carman property, Dr.
    McMahon calculated peak flow to occur at 1:00 a.m., September 13, at a rate of 15,080
    cfs under regulated flow, 15,016 cfs under unregulated flow, and 15,185 cfs under
    unimpaired flow. Dr. McMahon’s expert report records as his “observations,” that “[f]or all
    scenarios, the largest component of peak flow at the Orr and Carman properties is runoff
    from the North Fork Basin” and that peak flow from the Olympus Dam location arrives at
    the confluence of the Big Thompson River and the North Fork Big Thompson River,
    immediately upstream of plaintiffs’ properties, “1.5 hours or more after peak flow at
    Plaintiffs’ properties (both of which occur less than 15 minutes apart).”50 (alteration
    added). Dr. McMahon’s expert report also indicates the effect of the calculated flows on
    the flow depth at plaintiffs’ properties, stating,
    in the unimpaired Olympus Dam flow scenario, duration of flows above
    10,000 cfs at both properties increases by about an hour, and above 14,000
    cfs by about 30 minutes in comparison to the unregulated scenario. This
    result suggests that, without Olympus Dam in operation, bank erosion and
    undermining of structural foundations on the properties would have
    persisted longer and could have caused more damage than was
    experienced during the flood.
    50 Dr. McMahon’s expert report restates this calculation elsewhere as “[p]eak flow from
    Olympus Dam does not arrive until 1.5 to 2 hours after the Big Thompson River crests at
    the [plaintiffs’] properties.” (alterations added). As noted above, Dr. McMahon calculated
    peak flow as occurring at the Orr property at 12:45 a.m. on September 13, 2013, and at
    the Carman property at 1:00 a.m. on September 13, 2013. According to Dr. McMahon’s
    calculations, therefore, peak release from Olympus Dam did not arrive until at the earliest
    at 2:15 a.m., at the Orr property, and 2:30 a.m., at the Carman property. Plaintiffs’ expert
    Mr. Brown, by contrast, calculated that peak release from Olympus Dam “arrived at the
    [plaintiffs’] properties between 1.2 and 2.0 hours after release,” (alteration added), or
    between approximately 1:00 a.m. and 1:45 a.m. on September 13, 2013.
    68
    Dr. McMahon’s expert report includes his finding that “flow time series and flow-duration
    data generated by the HEC-HMS [Hydrologic Modeling System] model indicate that
    Olympus Dam as operated may have reduced peak flows, duration of high flows, and
    potential flood damages to Plaintiffs’ properties in comparison to those that would have
    naturally occurred without the dam.” (alteration added). In Dr. McMahon’s expert opinion,
    the September 2013 flood was an extreme event that would have damaged
    Plaintiffs’ properties in much the same fashion as they had been, no matter
    how closely spillway releases from Olympus Dam matched inflows to the
    reservoir, or how Adams Tunnel inflows and Olympus Tunnel diversions
    had been managed. Had Olympus Dam been operated such that spillway
    releases did not closely match inflows, overtopping and dam failure could
    potentially have resulted, causing even greater flood damages than had
    occurred and possible loss of life downstream in addition. Lastly, the
    unimpaired flow scenario demonstrates that Plaintiffs would have been
    worse off had Olympus Dam and tunnels not been in operation at the time.
    Defendant’s second expert witness, Dr. David Bowles, testified at trial that he has
    a Ph.D. in civil and environmental engineering, with a focus on water resources and
    hydrology. Dr. Bowles also testified that he is a licensed professional engineer and the
    owner and managing principal of RAC Engineers and Economists, LLC. Dr. Bowles
    produced an expert report which provides his “opinions on the effects on dam safety had
    the Bureau of Reclamation deviated from its operating rules by limiting releases from the
    Olympus Dam during the flood event that commenced on September 12, 2013.” Dr.
    Bowles’ expert report states:
    I was asked to evaluate the following three hypothetical cases of limiting
    spillway releases from Lake Estes throughout the September 2013 flood
    event, starting at the time that the operator arrived at Olympus Dam at about
    2:15 am on September 12, 2013, as follows:
    1. Limited by a constant 2.50-foot opening of a single spillway gate, which
    is the maximum opening for remote operation with no operator physically
    present at Olympus Dam.
    2. Limited to a constant 1.61-foot opening of a single spillway gate, which
    corresponds to the flow rate of 653 cubic feet per second (cfs), estimated
    by Arcadis at the time that the operator arrived at Olympus Dam at about
    2:15 am on September 12, 2013.
    3. Limited by all spillway gates remaining closed, which eliminates any
    release into the Big Thompson River.
    Dr. Bowles’ report indicates that Dr. Bowles performed a “reservoir routing” analysis to
    evaluate the hypotheticals, and the report explains: “reservoir routing involves adding
    inflows and subtracting releases from the starting storage volume to calculate the ending
    storage volume,” which can be used to determine the water surface elevation of the
    reservoir according to the “elevation-capacity relationship.” Dr. Bowles’ analysis
    69
    determined that, for the first hypothetical, “[t]he estimated peak reservoir water surface
    elevation is 7,482.5 feet,” with the following effects:
    a. Overtopping of the left abutment starting at Elevation 7481.2 feet for
    almost a day, resulting in a significant flow down the groin at the left
    abutment with the potential to initiate an erosional failure of the
    embankment dam.
    b. Exceeding the elevation of 7478 feet for more than three and one-half
    days, which is reported by Reclamation (2009, US_0076981) to be the
    threshold elevation for a sliding failure of the concrete gravity dam.
    c. Overtopping of the spillway gates at Elevation 7475 feet for almost five
    days, which, consistent with other dams, is specifically prohibited by
    Reclamation (2016, US_0077436) because this could damage the gates
    and possibly lead to a structural failure of the gates.
    d. Overtopping of the parapet wall on the concrete gravity dam on both
    sides of the spillway starting at Elevation 7481.9 feet for about half a day
    with the potential to initiate an erosional failure of the right end of the
    embankment dam.
    ...
    e. Overtopping of the downstream curb on the bridge over the concrete
    gravity spillway starting at Elevation 7478.75 feet for more than two and
    one-half days, resulting in flow over the right end of the embankment
    dam, which could initiate an erosional failure of this dam.
    f. Overtopping of the right abutment starting at Elevation 7481.9 feet for
    about half a day.
    (ellipsis added). Dr. Bowles found the same results with respect to the second and third
    hypotheticals as he did for the first hypothetical, except that the duration of each result
    was longer. For the second hypothetical, Dr. Bowles’ expert report indicates that the left
    abutment would overtop “for almost one and a half days,” the elevation threshold of 7,478
    feet would be exceeded “for more than five days,” the spillway gates would overtop “for
    more than six days,” the parapet wall would overtop “for more than half a day,” the
    downstream curb on the bridge would overtop “for more than four and one-half days,” and
    the right abutment would overtop “for more than half a day.” For the third hypothetical, Dr.
    Bowles’ expert report indicates that the left abutment would overtop “for about two and
    one-half days,” the elevation threshold of 7,478 feet would be exceeded “for well over six
    days,” the spillway gates would overtop “for well over six days,” the parapet wall would
    overtop “for more than one and one-half days,” the downstream curb on the bridge would
    overtop “for well over six days,” and the right abutment would overtop “for more than one
    and one-half days.” Dr. Bowles’ report concludes with Dr. Bowles’ opinion that all three
    hypotheticals “should be avoided if possible” because they “have the potential to lead to
    a failure of Olympus Dam as a result of overtopping or exceeding the sliding stability
    threshold,” which “would result in a sudden and life-threatening breach wave with a peak
    discharge rate many times higher than the peak release that actually occurred.”
    70
    Based on the conclusions of plaintiffs’ expert witness Mr. Brown, plaintiffs argue
    “that the increased storage flows caused by Olympus Dam (compared to if Olympus Dam
    was not present) was sufficient to cause the damage to Plaintiffs’ property.” (alteration
    added). According to plaintiffs, Mr. Brown’s conclusions “were based on a reasonable
    probability that the combination of the Olympus Dam storage flows plus natural flows
    caused the damage,” such that the water stored “during the day of September 12-13,
    2013,” when released, “increased and elongated the peak and erosive flows of the Big
    Thompson River” at plaintiffs’ properties. According to plaintiffs, Mr. Brown’s testimony
    indicated that water flowing into Lake Estes deposited any sediment it was carrying into
    the reservoir, and “‘bulking’ occurred as the Bureau released clean, ‘sediment-starved’
    water from the Olympus Dam and the water (described by Mr. Brown as ‘release flows’
    and ‘storage flows,’) picked up sediment, boulders, and debris as it [the water] flowed
    over several miles through the Big Thompson Canyon toward the plaintiffs’ property.”
    (alteration added). Plaintiffs argue that “[t]he bulking of the water increased the depth and
    velocity of the flood water flowing through the canyon over the night of September 12-13,
    2013,” while “had there been no Olympus Dam, the water passing through where Lake
    Estes is impounded would already have been bulked,” such that “for instance, 5000cfs
    flowing through would have essentially the same volume as it flowed through the canyon,”
    while the same amount “of unbulked water released from the Olympus Dam would
    increase as indicated” as it traveled down the canyon. (alteration added). Moreover,
    according to plaintiffs, Mr. Brown explained that “the Bureau’s release of storage flows
    overnight raised the volume, velocity, and erosion potential of the Big Thompson as it
    flowed past plaintiffs’ properties overnight and through the morning of Sep. 13 when the
    Orr home and Carman business were destroyed.”51 Plaintiffs argue that Mr. Brown based
    his model “on the Colorado Department of Transportation’s independent study results for
    stream basins,” which, according to plaintiffs, “is considered an authoritative analysis of
    the 2013 flood event by the hydrology community.”52
    Plaintiffs contend that defendant’s two expert witnesses, Dr. McMahon and Dr.
    Bowles,53 were not credible. Plaintiffs argue that Dr. McMahon’s testimony at trial agreed
    with plaintiffs’ characterization of bulking of water released from Olympus Dam, and
    plaintiffs argue, quoting Dr. McMahon, that “water passing through the spill gates, from
    the top of the pool, would be ‘relatively pure water without the rocks, debris, sediment in
    it’ and would ‘tend to bulk up again’” after being released from Olympus Dam. Plaintiffs
    argue that “Dr. McMahon steadfastly refused to acknowledge that sediment-laden, bulked
    51 Ms. Orr testified at trial that her home was partially destroyed by the September 2013
    flood.
    52As explained above, Mr. Brown’s expert report relied on data from the Phase One
    Memorandum that was included in the Colorado Department of Transportation 2014
    Hydrology Report. The Phase One Memorandum data was developed by Bob Jarrett of
    Applied Weather Associates, whereas the Colorado Department of Transportation 2014
    Hydrology Report was prepared by the Jacobs Engineering Group.
    53 The credibility of defendant’s expert Dr. Bowles is also discussion below with respect
    to the application of the necessity doctrine.
    71
    inflowing water had a higher proportion of sediment to water than relatively pure, unbulked
    water released from Lake Estes.” Moreover, plaintiffs argue that Dr. McMahon “did not
    consider the fact that 97% of the water impounded in Lake Estes is ‘project water,’” stored
    for use by the C-BT, nor “that Lake Estes was nearly full when the storm came and that
    overnight on September 12-13 and through the morning when the storm was at its peak
    the Bureau chose to draw Lake Estes down and thus release stored ‘project water.’”
    Plaintiffs further argue that Dr. McMahon was unfamiliar with plaintiffs’ properties or their
    riverbanks before the September 2013 storm, and that Dr. McMahon’s model relied on
    geometric data that reflected the properties’ condition in 2015, after the September 2013
    storm, rather than before the September 2013 storm. In addition, plaintiffs further argue
    that Dr. McMahon’s model was based on insufficiently specific rainfall data which did not
    account for different runoff amounts at different locations in the Big Thompson River
    Canyon. Furthermore, plaintiffs argue, based on Mr. Brown’s response to Dr. McMahon’s
    model, that Dr. McMahon’s model could not be verified by reference to the Colorado
    Department of Transportation’s data, and that “measurements like high water marks”
    were not used to calibrate Dr. McMahon’s model. Plaintiffs also argue that Dr. McMahon’s
    model indicated that water took three hours to reach plaintiffs’ properties after being
    released from Olympus Dam, while plaintiffs claim that released water “actually took half
    that time” to travel that distance, because plaintiffs describe the Bureau of Reclamation’s
    Post Incident Analysis Report as stating “it took four hours for a wave of 2700cfs released
    from the Olympus Dam to reach the mouth of the canyon.” Moreover, plaintiffs argue that
    Dr. McMahon did not account for the absence of Lake Estes in Dr. McMahon’s model of
    a scenario without Olympus Dam, which plaintiffs argue “may” account for Dr. McMahon’s
    conclusion that flooding would have been worse absent Olympus Dam.
    With respect to Dr. Bowles, as explained further below, plaintiffs argue that Dr.
    Bowles’ assessment of the danger posed to Olympus Dam by the September 2013 storm
    is inconsistent with the testimony of Mr. Bailey and Ms. O’Brien, who plaintiffs argue “both
    testified that the Olympus Dam was never in danger of failing or breaching.” Plaintiffs
    state that because Dr. Bowles only analyzed hypothetical scenarios of fixed releases from
    Olympus Dam, “Dr. Bowles offered no opinions about what actually occurred in the 2013
    storm.” Plaintiffs further argue that “Dr. Bowles’ calculations were biased by selecting an
    arbitrarily high level of water to start his calculations as opposed to the much lower levels
    actually present at 0815 that morning” on September 12, 2013. Moreover, according to
    plaintiffs, “Dr. Bowles had no opinion on how long the dam could safely withstand a gate
    being overtopped with a lake elevation over 7475 feet.”
    Defendant challenges plaintiffs’ characterization of the expert witnesses’ findings.
    Defendant not only argues that “it [defendant] did not cause the flooding and erosion of
    Plaintiffs’ properties,” but also that plaintiffs’ expert Mr. Brown’s conclusions “on this issue
    do not establish causation as a matter of law.” (alteration added). Defendant asserts that
    Mr. Brown “conducted no analysis of what would have happened absent the dam,” and
    “did not conduct any hydrologic modeling,” but instead only “took the peak flow results
    that he believed the Colorado Department of Transportation calculated for the September
    2013 storm at the confluence of the North Fork Big Thompson and Big Thompson Rivers
    and Drake,” and Mr. Brown “subtracted a single Olympus Dam release from that number
    (with adjustments for potential debris in the flow).” Defendant contends that Mr. Brown
    72
    did not account for the Olympus Tunnel, which the Bureau used “to take water off the Big
    Thompson River” during the September 2013 storm, and which “additional water would
    have contributed to the flow at Plaintiffs’ properties in the absent-the-dam world.”
    Moreover, defendant argues that Mr. Brown “did not calculate and does not know
    when peak flow occurred at the confluence or at Plaintiffs’ properties,” because the
    Colorado Department of Transportation 2014 Hydrology Report on which Mr. Brown
    based his calculations “did not determine the time of any peak flows.” According to
    defendant, Mr. Brown “cannot credibly opine that there would have been no flooding or
    erosion if not for the storage flow,” because “he admitted at trial that erosion would have
    occurred at the properties absent the storage release he identified,” (emphasis in
    original), but “Mr. Brown did not and could not quantify the difference in erosion between
    his ‘theoretical peak flow’ and the peak flow he believed occurred during the storm.”
    Defendant points out that Mr. Brown’s “lowest ‘theoretical peak flow’” was 13,356 cfs,
    which, according to the Emergency Action Plan for Olympus Dam, was over the 1,500 cfs
    of water needed to “begin to flood permanent residences” and over the 6,000 cfs of water
    needed to “inundate most structures in the canyon.” Defendant argues that absent
    Olympus Dam, “even more water would have been in the river at the time of peak inflow
    to Lake Estes.”
    Moreover, defendant also argues that plaintiffs’ expert Mr. Brown’s modeling was
    based on a misunderstanding of the Colorado Department of Transportation data relating
    to the September 2013 storm. According to defendant, Mr. Brown’s calculations are
    based on peak flow estimates from the Phase One Memorandum included in the
    Colorado Department of Transportation 2014 Hydrology Report, rather than from the
    report itself, and “the July 2014 memorandum was a preliminary report of peak flow
    estimates based on field observations of high water marks” rather than the result of
    modeling. Defendant argues that because Mr. Brown relied on the Phase One
    Memorandum peak flow estimates, rather than on the Colorado Department of
    Transportation 2014 Hydrology Report’s calculated peak flows, the court should “reject
    his work and opinions.”
    Defendant additionally argues that “[w]ater was already flooding the Carmans’ yard
    by 10 a.m. on September 12,” when flow in the Big Thompson River “was only 11,000
    cfs” according to the analysis of defendant’s expert Dr. McMahon, and the river was
    “starting to rise out of its banks and onto” Ms. Orr’s property “by the morning of September
    12,” which, according to defendant, indicates that plaintiffs’ properties were flooding hours
    before the 722 cfs storage flow release from Olympus Dam identified by Mr. Brown.
    (alteration added). Defendant emphasizes the extent of the flooding at plaintiffs’
    properties immediately prior to plaintiffs’ leaving their homes, resulting in “three to four
    feet of water” in the Carmans’ basement at approximately 6:00 p.m. on September 12,
    2013, and ripping Ms. Orr’s “picnic table out of its concrete moorings” at approximately
    11:30 p.m. on September 12, all of which occurred before the storage flow releases
    identified by Mr. Brown and while the total flow in the river was below Mr. Brown’s
    calculated theoretical peak flow. (emphasis in original).
    73
    Defendant also relies on its expert witness, Dr. McMahon, to argue “that Plaintiffs
    would have suffered flooding and erosion absent Olympus Dam,” and that “Plaintiffs
    would have been worse off absent Olympus Dam.” According to defendant, quoting from
    Dr. McMahon’s expert report, Dr. McMahon’s “unimpaired scenario ‘represents the
    without-[C-BT] project condition, in which flow at the site of Olympus Dam is the flow that
    would have naturally occurred during the 2013 flood had the dam and [Lake Estes]
    reservoir, Adams Tunnel, and Olympus Tunnel never been built.’” (alterations added).
    Defendant argues that Dr. McMahon’s model is more credible than Mr. Brown’s, in part
    because Dr. McMahon’s calculated flows for the storm as it actually happened were
    “within approximately 0.9%” of the calculated flows in the Colorado Department of
    Transportation 2014 Hydrology Report. Defendant further emphasizes that the
    September 2013 storm “was a storm of historic proportions,” and that “extreme amounts
    of water would have flowed downstream through Big Thompson Canyon regardless of
    Olympus Dam.” Moreover, because Dr. McMahon calculated the North Fork Big
    Thompson River to have had over 7,000 cfs in peak flow, and the North Fork Big
    Thompson River’s flow was not affected by the Bureau’s operation of Olympus Dam,
    defendant argues that “Plaintiffs would have suffered severe flooding and erosion absent
    Olympus dam.”
    The United States Court of Appeals for the Federal Circuit addressed the causation
    requirement of Arkansas Game & Fish Commission in its decision in St. Bernard Parish
    Government v. United States, 
    887 F.3d 1354
    , which, similar to the above captioned case,
    was a flooding case. The Federal Circuit in St. Bernard Parish explained that “[c]ausation
    requires a showing of ‘what would have occurred’ if the government had not acted,” and
    that “a plaintiff must show that in the ordinary course of events, absent government action,
    plaintiffs would not have suffered the injury.” 
    Id. at 1362
     (alteration added) (quoting United
    States v. Archer, 
    241 U.S. 119
    , 132 (1916)). The Federal Circuit further explained:
    Thus, for example, in Archer, plaintiffs claimed that the government’s
    construction of a dike on their property constituted a taking because the
    construction of the dike caused depositing of sand and gravel on their land.
    
    241 U.S. at 128
    , 
    36 S. Ct. 521
    . Due to the possibility that without the dike,
    a river may have flowed through plaintiff’s property and permanently
    submerged the property, the Supreme Court remanded the case to
    determine whether the testimony demonstrated “what would have occurred
    if the dike had not been constructed.” 
    Id. at 132
    , 
    36 S. Ct. 521
    . In
    Sanguinetti[v. United States], plaintiffs brought a takings claim alleging that
    a canal built by the government caused flooding damage. 264 U.S. [146,]
    147, 
    44 S. Ct. 264
     [(1924)]. The Court noted the relevance of whether “[t]he
    land would have been flooded if the canal had not been constructed.” Id.;
    see Danforth v. United States, 
    308 U.S. 271
    , 286, 
    60 S. Ct. 231
    , 
    84 L. Ed. 240
     (1939) (“The Government could become liable for a taking . . . by such
    construction as would put upon this land a burden, actually experienced, of
    caring for floods greater than it bore prior to the construction.”); see also
    Arkansas Game, 
    568 U.S. at 34
    , 
    133 S. Ct. 511
    .
    74
    Our cases are to the same effect. In Accardi v. United States, the
    government built a dam, and after a severe storm with unexpected
    precipitation, water flowed onto plaintiffs’ property. 
    599 F.2d 423
     (Ct. Cl.
    1979). The court explained that “plaintiffs have wholly failed to show that
    defendant's construction or operation of the [dam] subjected their lands to
    any additional flooding above what would have occurred in consequence of
    the severe . . . storm had defendant not constructed the [dam] at all.” 
    Id.
     at
    429–30. The court then held that “[i]n these circumstances, there has been
    no taking of plaintiffs’ property.” 
    Id. at 430
    . Thus, the causation analysis
    requires the plaintiff to establish what damage would have occurred without
    government action.
    St. Bernard Par. Gov’t v. United States, 
    887 F.3d at 1362-63
     (emphasis in original; first
    three alterations added; footnote omitted). In the St. Bernard Parish case, the Federal
    Circuit held the plaintiffs “failed to present evidence comparing the flood damage that
    actually occurred to the flood damage that would have occurred if there had been no
    government action at all,” in particular “fail[ing] to take account of other government
    actions” such as “the construction of a vast system of levees to protect against hurricane
    damage” which the Federal Circuit held “mitigated the impact of MRGO [Mississippi River
    Gulf Outlet] and may well have placed the plaintiffs in a better position than if the
    government had taken no action at all.” 
    Id. at 1363
     (alterations added; footnote omitted).
    Moreover, in St. Bernard Parish, the Federal Circuit rejected plaintiffs’ argument
    for causation on the basis only of the Mississippi River Gulf Outlet construction and
    operation, without considering the impact of the construction of another federal
    government structure, the Lake Pontchartrain and Vicinity Hurricane Protection Project.
    See 
    id.
     The Federal Circuit explained that plaintiffs had considered “isolated government
    actions,” which was “inconsistent with governing Supreme Court and Federal Circuit
    authority,” concluding: “These cases establish that the causation analysis must consider
    the impact of the entirety of government actions that address the relevant risk.” 
    Id. at 1364
    .
    In St. Bernard Parish, the Federal Circuit referred to a United States Supreme
    Court case, United States v. Sponenbarger, 
    308 U.S. 256
     (1939). In United States v.
    Sponenbarger, the Supreme Court rejected the claim of an owner of flood-prone land
    within a government flood control plan, see 
    id. at 263-64
    , in part, because “[t]he
    Government has not subjected respondent’s land to any additional flooding, above what
    would occur if the Government had not acted.” See 
    id. at 266
     (alteration added). The
    Supreme Court in Sponenbarger further held that there were “far reaching benefits which
    respondent’s land enjoys from the Government’s entire program” and that “if
    governmental activities inflict slight damage upon land in one respect and actually confer
    great benefits when measured in the whole, to compensate the landowner further would
    be to grant him a special bounty.” 
    Id. at 266-67
    .
    In St. Bernard Parish Government v. United States, 
    887 F.3d at 1364-65
    , the
    United States Court of Appeals for the Federal Circuit also referred to the Federal Circuit’s
    decision in Arkansas Game & Fish Commission on remand from the Supreme Court. See
    75
    Arkansas Game & Fish Comm’n v. United States, 
    736 F.3d 1364
     (Fed. Cir. 2013).
    Applying the causation analysis of the Supreme Court’s Arkansas Game & Fish
    Commission framework, the Federal Circuit found persuasive testimony by experts that
    “deviations,” or water releases contrary to policy, had “caused the flooding,” which in turn
    caused the damage in that case. See Arkansas Game & Fish Comm’n v. United States,
    
    736 F.3d at 1371
    . The Federal Circuit explained in Arkansas Game & Fish Commission
    on remand, “the proper comparison would be between the flooding that occurred prior to
    the construction of Clearwater Dam and the flooding that occurred during the deviation
    period,” rather than limiting the analysis to the period in which the policy had been in
    place. See 
    id.
     at 1372 n.2. According to the Federal Circuit in St. Bernard Parish, the
    explanation in the Arkansas Game & Fish Commission opinion on remand “emphasiz[ed]
    that the causation analysis considers causation based on the entirety of government
    action, not merely the deviation from the original water-release policy.” See St. Bernard
    Par. Gov’t v. United States, 
    887 F.3d at 1365
     (alteration added).
    In addition, in St. Bernard Parish, the Federal Circuit also cited John B. Hardwicke
    Co. v. United States, 
    199 Ct. Cl. 388
    , 
    467 F.2d 488
     (1972), which concerned flooding of
    claimants’ land by water diverted by the closing of a dam on the Rio Grande. See 
    id. at 390
    . In Hardwicke, the United States Court of Claims found that two dams had been
    constructed on the river which impacted flooding on the claimants’ land, Falcon Dam, the
    operation of which “reduced the anticipated incidence of flooding on the land at issue from
    once every two years to once every ten years,” and Anzalduas Dam, the operation of
    which “increased the incidence of flooding on the land in question to once every seven or
    eight years.” See 
    id. at 391-92
    . The Court of Claims observed that with both dams, “the
    expectation of flooding was still far less than it would have been if there had been no flood
    control program at all,” 
    id. at 392
    , and held that “plaintiffs cannot base a taking claim on
    the hypothesis that they can garner the benefit conferred by Falcon, without deduction for
    the probable detriment when Anzalduas comes into being too.” 
    Id. at 394
    .
    The Federal Circuit in St. Bernard Parish also explained with respect to
    consideration of the entirety of the government actions “in determining causation,” that
    “[w]hen the government takes actions that are directly related to the preventing the same
    type of injury on the same property where the damage occurred, such action must be
    taken into account even if the two actions were not the result of the same project.” St.
    Bernard Par. Gov’t v. United States, 
    887 F.3d at 1366
     (alteration added). Moreover,
    “[w]hen government action mitigates the type of adverse impact that is alleged to be a
    taking, it must be considered in the causation analysis, regardless of whether it was
    formally related to the government project that contributed to the harm.” 
    Id. at 1367
    (alteration added).
    The United States Court of Claims’ decision in Accardi v. United States, 
    220 Ct. Cl. 347
    , 
    599 F.2d 423
    , is also relevant to the causation analysis in the above captioned
    case. The plaintiffs in Accardi owned property downstream of Trinity Dam on the Trinity
    River in California, see id. at 349-50, and alleged that the Bureau of Reclamation’s
    operation of Trinity Dam resulted in takings of their properties in the form of flooding during
    a 1974 storm. See id. at 355-56. The Court of Claims rejected the Accardi plaintiffs’
    arguments, explaining that “[h]ad Trinity Dam not been in operation in January 1974,
    76
    plaintiffs’ real properties in the Poker Bar area would have experienced the full force of a
    peak inflow of 107,700 c.f.s., and of a mean daily inflow of 72,550 c.f.s. of water,” whereas
    Trinity Dam’s operation involved releases “of no more than 14,800 c.f.s. of water, with
    releases at that level persisting for less than 30 minutes.” See id. at 357 (alteration
    added). The Court of Claims decision found “that the flooding which actually occurred in
    consequence of that storm was far less than would have been the case had the Trinity
    River division never been built,” and, therefore, held that the United States had not taken
    the plaintiffs’ properties. Id. at 358.
    Precedents of the United States Supreme Court, the United States Court of
    Appeals for the Federal Circuit, and the United States Court of Claims discussed above
    demonstrate that plaintiffs must prove that absent the government’s actions, namely the
    construction and operation of Olympus Dam and the other C-BT facilities, including the
    releases of water from Olympus Dam into the Big Thompson River, the damage to
    plaintiffs’ properties would not have occurred. The parties have focused on separate
    aspects of the causation inquiry in their arguments in post-trial briefing. Plaintiffs’
    arguments concentrated on the releases from the Olympus Dam during the course of the
    September 2013 storm, and, therefore, plaintiffs have focused on the operation of the
    Olympus Dam by the Bureau of Reclamation, including the peak water releases of
    September 12 and 13, 2013. Defendant, by contrast, focused its argument on the
    existence of the Olympus Dam and other C-BT structures, concentrating on the
    hypothetical world “absent the dam,” and comparing the September 2013 storm as it
    happened to the September 2013 storm as it would have transpired if Olympus Dam, and
    other C-BT structures, did not exist. In contrast to both parties’ approaches, however, the
    Federal Circuit explained in St. Bernard Parish that plaintiffs’ burden is to prove causation
    in light of “the entirety of government actions that address the relevant risk.” See St.
    Bernard Par. Gov’t v. United States, 
    887 F.3d at 1364
    . Because both the existence of the
    Olympus Dam generally, and the operation of Olympus Dam during the September 2013
    storm, including specifically the releases from Olympus Dam into the Big Thompson
    River, “address the relevant risk,” 
    id.,
     by affecting the flow of water in the Big Thompson
    River, both the existence of the Olympus Dam and the operation, including the water
    releases, of the Olympus Dam, must be considered in the causation analysis in the above
    captioned case.
    Multiple witnesses from the Bureau of Reclamation testified that Olympus Dam is
    “not a flood control dam,” but is rather a small and “reactive” reservoir, which can neither
    store nor release large quantities of water. The data in the Colorado Department of
    Transportation 2014 Hydrology Report supports this assessment of the Olympus Dam.
    The Colorado Department of Transportation 2014 Hydrology Report calculated that the
    Big Thompson River above the Drake confluence had a peak flow between 7,534 cfs and
    7,566 cfs, while the North Fork Big Thompson River at the Drake confluence had a peak
    flow between 7,706 cfs and 7,723 cfs. Therefore, even when the Big Thompson River
    above Drake was at its maximum flow rate during the September 2013 storm, the Big
    Thompson River still had less flow rate than the maximum flow rate of the North Fork Big
    Thompson River. This discrepancy between the Big Thompson River and the North Fork
    Big Thompson River prior to the two joining at the Drake confluence indicates that, even
    at its most intense flow, the Big Thompson River above Drake contributed less to the
    77
    combined flow at the plaintiffs’ properties than did the North Fork Big Thompson River.
    Moreover, only the Big Thompson River’s flow was impacted by releases from Olympus
    Dam, and the water released from Olympus Dam also mixed with rainfall and other runoff
    in the thirteen miles between Olympus Dam and the Drake confluence. Therefore,
    although the amounts released may have been significant for Olympus Dam, they were
    less significant in the context of the total amount of water flowing through both rivers and
    joining at the confluence at Drake.
    The model created by Dr. McMahon, defendant’s expert, indicates that the
    presence of Olympus Dam resulted in a measurable decease in peak flow rate, to 15,011
    cfs at plaintiffs’ properties, compared to the “unimpaired flow” model, with a peak flow of
    15,108 cfs at plaintiffs’ properties. When considering the totality of all government actions
    taken during the September 2013 storm, the flow of water could have been far greater
    absent the dam. As the testimonies of several of the Bureau of Reclamation employees
    indicate, the water schedulers continuously monitored the water elevation in Lake Estes
    and increased their outflows through Olympus Dam gradually to account for rising water
    elevation. They testified that this constant monitoring and adjustment of spillway releases
    was carefully considered and administered to keep the Olympus Dam intact. As
    defendant’s expert, Dr. Bowles’ model suggests, if the government officials had not
    engaged in their gradual increases of releases of water downstream, or even had left
    releases constant, it could have produced, at minimum, days of water overtopping certain
    portions of Olympus Dam.54 As Dr. Bowles, as well as a number of the Bureau of
    Reclamation employees, testified, overtopping of even the lowest portions of Olympus
    Dam, the closed spillway gates, could have resulted in dam failure and uncontrolled
    releases downstream, which would have exceeded the peak flows experienced by
    plaintiffs’ properties.
    Contrary to plaintiffs’ arguments, the expert report prepared by plaintiffs’ expert Mr.
    Brown supports this assessment. As discussed above, Mr. Brown calculated a release of
    722 cfs of stored water from Lake Estes through Olympus Dam at the time of peak release
    at 11:45 p.m. on September 12, 2013. Mr. Brown further applied three bulking factors to
    his calculated storage release, and the largest bulking factor, 2.0, would increase the
    volume of the storage flow to 1,444 cfs. The Colorado Department of Transportation’s
    2014 Hydrology Report, however, calculated the peak flow of the Big Thompson River
    below the confluence at Drake to be between 14,728 cfs and 14,731 cfs. Even assuming
    that the largest bulking factor calculated by Mr. Brown was accurate, there would still have
    been at least 13,284 cfs in the peak flow at plaintiffs’ properties downstream of the Drake
    confluence if no storage flows, as identified by Mr. Brown, had been released.
    Further, according to the trial testimony of Ms. Orr, Mr. Carman, and Mrs. Carman,
    water in the Big Thompson River adjacent to plaintiffs’ properties rose throughout the day
    of September 12, 2013, at first in the banks of the Big Thompson River and then onto the
    54 As discussed above, Dr. Bowles calculated that if Olympus Dam had been limited, for
    example, to a single gate opening with an opening of 2.50 feet, “the maximum opening
    for remote operation,” that would have resulted in an overtopping of the closed spillway
    gates “for almost five days.”
    78
    surrounding property. Water entered the lower yard of the Carmans’ property, which was
    close to the Big Thompson River, and then the basement of the Carmans’ house, between
    the late morning and the early afternoon of September 12. Around 6:00 p.m. on
    September 12, shortly before the Carmans left their property to spend the night at their
    neighbor’s house, the water was three to four feet deep in the Carmans’ basement. By
    approximately 11:30 p.m., shortly before Ms. Orr left her property for her neighbor’s
    house, Ms. Orr saw the still rising water of the river rip her picnic table out of the concrete
    in which it was set. These events, documenting the encroachment of the floodwaters onto
    plaintiffs’ properties, all occurred prior to the peak release from Olympus Dam. Moreover,
    even assuming that the peak release from Olympus Dam coincided with the peak flow in
    the Big Thompson River near plaintiffs’ properties, the peak release’s contribution to the
    peak flow at plaintiffs’ properties would amount to less than ten percent of the peak flow
    at either the Orr or Carman properties.
    Based on the evidence in the record before the court and the testimony of the
    plaintiffs, the flooding of plaintiffs’ properties began hours before the peak releases were
    made from Olympus Dam in response to the September 2013 storm, and further hours
    before those releases arrived at plaintiffs’ properties. Moreover, when the peak releases
    from Olympus Dam did arrive, the contribution of the peak releases, even with the
    maximum bulking factor proposed by plaintiff’s expert Mr. Brown, appear to have
    contributed no more than 1,444 cfs out of the 14,728 cfs to 14,731 cfs peak flow which
    was present in the Big Thompson River near plaintiffs’ properties. Additionally, as the
    data contained in the Colorado Department of Transportation 2014 Hydrology Report
    demonstrates, more than half of the water in the Big Thompson River near plaintiffs’
    properties came from the North Fork Big Thompson River above the confluence at Drake,
    rather than coming directly from the Big Thompson River above Drake into which
    Olympus Dam releases water. Based on the testimony at trial, specifically the testimony
    addressing the Bureau employees’ actions during the September 2013 storm, and the
    exhibits in the record, the court finds that plaintiffs have failed to establish that the Bureau
    of Reclamation’s operation of Olympus Dam during the September 2013 storm, in
    particular the Bureau’s peak releases during the storm on September 12 and 13, 2013,
    caused the damage at plaintiffs’ properties. Because plaintiffs have failed to carry their
    burden to establish that the Bureau of Reclamation’s actions, including the existence of
    the Olympus Dam and defendant’s operation of the Olympus Dam, including the water
    releases, during the September 2013 storm, caused the flooding of plaintiffs’ properties,
    plaintiffs cannot succeed on their takings claims under the Arkansas Game & Fish
    Commission analysis. See St. Bernard Par. Gov’t v. United States, 
    887 F.3d at 1364
    ;
    Arkansas Game & Fish Comm’n v. United States, 
    736 F.3d at 1371
    . Although plaintiffs
    have not demonstrated causation, the court briefly addresses below, for the benefit of the
    parties’ understanding, the remaining Arkansas Game & Fish Commission factors: time
    and duration, intent or foreseeability, reasonableness of investment-backed expectations,
    and severity. The court reiterates, however, that because plaintiffs have not demonstrated
    causation, plaintiffs have not met their burden to prove a taking of their properties.
    79
    Time and Duration
    To continue with a discussion of the Arkansas Game & Fish Commission factors,
    plaintiffs argue with respect to time and duration that “the floodwaters re-routed the river
    and permanently deprived the plaintiffs of their property by eroding the banks of their
    properties,” and that “the floodwaters temporarily inundated other parts of the Orr and
    Carman properties.” According to plaintiffs, “repetition is not necessary when intent or
    foreseeability is established.” (citing Eyherabide v. United States, 
    170 Ct. Cl. 598
    , 604-
    05, 
    345 F.2d 565
    , 569 (1965)). Plaintiffs argue that requiring repetition in order to prove
    a taking would amount to allowing the government “one-free-flood” before being subject
    to liability. Defendant responds that “the Bureau did not preempt Plaintiffs’ rights to enjoy
    their properties for an extended period,” but rather “[t]his was a one-time, limited duration
    flood event.” (alteration added).
    The Supreme Court in United States v. Cress stated that “[t]here is no difference
    of kind, but only of degree, between a permanent condition of continual overflow by
    backwater and a permanent liability to intermittent but inevitably recurring overflows; and,
    on principle, the right to compensation must arise in the one case as in the other.” United
    States v. Cress, 
    243 U.S. at 328
     (alteration added). Moreover, as a Judge of the Court of
    Federal Claims in In re Upstream Addicks and Barker (Texas) Flood-Control Reservoirs,
    
    146 Fed. Cl. 219
    , held, when “the government’s actions have subjected plaintiffs’ private
    properties to the possibility, rather probability, of government induced flooding,” the length
    of the taking “is measured by a permanent right to inundate the property with impounded
    flood waters.” 
    Id. at 250
    ; see also Quebedeaux v. United States, 
    112 Fed. Cl. 317
    , 323
    (2013) (“[I]t is conceivable that a takings might lie where defendant, using a permanent
    structure, purposely floods a property once and expressly reserves the right to do so in
    the future.” (alteration added)).
    As indicated above, the United States Supreme Court in Cedar Point Nursery v.
    Hassid also addressed the durational difference between a taking and a tort. The
    Supreme Court in Cedar Point Nursery quoted the Supreme Court’s earlier decision in
    Portsmouth Harbor Land & Hotel Co. v. United States, 
    260 U.S. 327
    , explaining that
    “‘[w]hile a single act may not be enough, a continuance of them in sufficient number and
    for a sufficient time may prove [the intent to take property]. Every successive trespass
    adds to the force of the evidence.’” Cedar Point Nursery v. Hassid, 141 S. Ct. at 2078
    (first alteration added) (quoting Portsmouth Harbor Land & Hotel Co. v. United States,
    
    260 U.S. at 329-30
    ). The Portsmouth Harbor case concerned a resort property which
    adjoined property of the United States government, “upon which the Government has
    erected a fort, the guns of which have a range over the whole sea front of the claimants’
    property.” See Portsmouth Harbor Land & Hotel Co. v. United States, 
    260 U.S. at 328
    .
    The Supreme Court in Portsmouth Harbor explained that in prior cases concerning the
    same property,
    the mere erection of the fort and the fact that guns were fired over the
    claimants’ land upon two occasions about two years and a half before the
    suit was brought, coupled with the apprehension that the firing would be
    repeated, but with no proof of intent to repeat it other than the facts stated,
    80
    did not require the finding of an appropriation and a promise to pay by the
    United States,
    nor did “‘some occasional subsequent acts of gun fire’” effect a taking. 
    Id. at 328
     (quoting
    Portsmouth Harbor Land & Hotel Co. v. United States, 
    250 U.S. 1
    , 2 (1919)). The
    Supreme Court in the Portsmouth Harbor decision considered additional actions the
    government had taken since the prior cases at the same location, namely that “the United
    States has set up heavy coast defence [sic] guns with the intention of firing them over the
    claimants’ land and without the intent or ability to fire them except over that land” and that
    the government “has established upon that land a fire control station and service, and in
    December, 1920, it again discharged all of the guns over and across the same land.” See
    id. at 329 (alteration added). The Supreme Court concluded that “[t]he establishment of
    a fire control is an indication of an abiding purpose” and therefore that “the specific facts
    set forth would warrant a finding that a servitude has been imposed.” Id. at 330 (alteration
    added).
    The United States Supreme Court in Cedar Point Nursery also favorably cited the
    decision of the United States Court of Appeals for the Federal Circuit in Hendler v. United
    States, 
    952 F.2d 1364
     (Fed. Cir. 1991), in which the Federal Circuit “identif[ied] a
    ‘truckdriver parking on someone’s vacant land to eat lunch’ as an example of mere
    trespass.” See Cedar Point Nursery v. Hassid, 141 S. Ct. at 2078 (alteration added)
    (quoting Hendler v. United States, 952 F.2d at 1377). The Federal Circuit’s decision in
    Hendler concerned the Environmental Protection Agency’s efforts “to combat ground
    water pollution from a major hazardous waste site, the Stringfellow Acid Pits in California,”
    and “the Government decided to locate ground water wells and associated equipment in
    the general area of the acid pits,” including “nearby properties” owned by the Hendler
    plaintiffs. See Hendler v. United States, 952 F.2d at 1367. The Federal Circuit in Hendler
    addressed the durational analysis in takings cases by example:
    Occasionally an issue arose as to whether the government's activity was so
    short lived as to be more like the tort of trespass than a taking of property.
    The distinction between the government vehicle parked one day on O’s land
    while the driver eats lunch, on the one hand, and the entry on O’s land by
    the government for the purpose of establishing a long term storage lot for
    vehicles and equipment, on the other, is clear enough.
    Id. at 1371 (citing J. SACKMAN, NICHOLS' THE LAW OF EMINENT DOMAIN § 8 (1991)). With
    respect to the durational analysis, the Federal Circuit has explained, “[a] taking can be for
    a limited term—what is ‘taken’ is, in the language of real property law, an estate for years,
    that is, a term of finite duration as distinct from the infinite term of an estate in fee simple
    absolute.” Id. at 1376 (alteration added). Recalling its example of the driver stopping to
    eat lunch, the Federal Circuit further explained that the word “temporary” “logically refers
    to those governmental activities which involve an occupancy that is transient and
    relatively inconsequential, and thus properly can be viewed as no more than a common
    81
    law trespass quare clausum fregit.[55] Our truckdriver parking on someone’s vacant land
    to eat lunch is an example.” Id. at 1377 (footnote added).
    Plaintiffs indicate in their trial testimony that they can recall two occasions on which
    their properties flooded, once in 1976, and again in 2013, in the storm at issue in the
    above captioned case. Plaintiffs have not testified to, nor does any evidence in the record
    indicate, that other significant floods have occurred in the Big Thompson River Canyon
    which have affected plaintiffs’ properties. There also is no evidence that the Bureau of
    Reclamation specifically “reserve[d] the right,” either at the time of the September 2013
    storm or since, to flood plaintiffs’ properties again. See Quebedeaux v. United States, 
    112 Fed. Cl. at 323
     (alteration added). The lack of a reservation of rights to flood the plaintiffs’
    properties again, as well as the infrequency of flooding, twice in 37 years, indicates that,
    rather than a probability of future “government induced flooding,” In re Upstream Addicks
    and Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 250, or “a permanent
    liability to intermittent but inevitably recurring overflows,” the flooding of plaintiffs’
    properties was an infrequent and unusual event. See United States v. Cress, 
    243 U.S. at 328
    . Additionally, the parties jointly stipulated that “[t]he annual exceedance probability of
    the September 2013 storm event ranged as low as 0.1%. In other words, the September
    2013 storms may have been a 1,000-year storm event.” (alteration added). Plaintiffs’
    expert Mr. Brown, similarly, determined that plaintiffs’ properties experienced flooding for
    approximately eighteen-and-a-half hours. Moreover, as plaintiffs testified at trial, the
    consequential flooding of Ms. Orr’s property occurred from the evening of September 12
    to the morning of September 13, 2013. The flooding of Mr. and Mrs. Carman’s property,
    which had a large portion of land that was closer to the river and in the flood plain, began
    in the afternoon of September 12, and by mid-morning of September 13, the water had
    receded enough to allow the Carmans to re-enter their land. Accordingly, the flooding
    which damaged plaintiffs’ properties, as well as being the first flood to occur since 1976
    in the Big Thompson River Canyon, lasted less than a full day. Therefore, the flooding of
    plaintiffs’ properties was “transient and relatively inconsequential” in terms of the duration
    of the alleged taking. See Hendler v. United States, 952 F.2d at 1377. Accordingly,
    plaintiffs have not carried their burden to demonstrate the time and duration element of
    the Arkansas Game & Fish Commission analysis.
    Intent or Foreseeability
    The United States Supreme Court in Arkansas Game & Fish Commission stated
    that “[a]lso relevant to the takings inquiry is the degree to which the invasion is intended
    or is the foreseeable result of authorized government action.” Arkansas Game & Fish
    Commission v. United States, 
    568 U.S. at 39
     (alteration added). Subsequently, a Judge
    of the Court of Federal Claims explained that, under this inquiry, “[a] taking occurs either
    where the government intended to invade the property or where the invasion is the ‘direct,
    55“Quare clausum fregit” is a Latin phrase meaning “[w]hy he broke the close.” See Quare
    Clausum Fregit, BLACK’S LAW DICTIONARY (11th ed. 2019) (alteration added). A “trespass
    quare clausum fregit” is a tort defined as “[a] person’s unlawful entry on another’s land
    that is visibly enclosed.” Trespass, BLACK’S LAW DICTIONARY (11th ed. 2019) (alteration
    added).
    82
    natural, or probable result of an authorized activity and not the incidental or consequential
    inquiry inflicted by the action.’” In re Upstream Addicks and Barker (Texas) Flood-Control
    Reservoirs, 146 Fed. Cl. at 254 (alteration added) (quoting Ridge Line, Inc. v. United
    States, 
    346 F.3d at 1355
     (internal quotation omitted)). Moreover, “[d]espite being
    separate inquiries, the two factors are interrelated—one cannot find intent without
    foreseeability; but what is an objectively foreseeable result may not have been the
    intended result.” In re Upstream Addicks and Barker (Texas) Flood-Control Reservoirs,
    146 Fed. Cl. at 254 (alteration added) (citing John Horstmann Co. v. United States, 
    257 U.S. 138
    , 146 (1921); Columbia Basin Orchard v. United States, 
    132 Ct. Cl. 445
    , 452,
    
    132 F. Supp. 707
    , 711 (1955)). The United States Court of Appeals for the Federal Circuit
    in Moden v. United States, 
    404 F.3d 1335
     (Fed. Cir. 2005), explained that a “plaintiff must
    prove that the government should have predicted or foreseen the resulting injury.” 
    Id. at 1343
    . Moreover, the flooding must be “‘the actual and natural consequence of the
    government’s act,’” but “injury may not be foreseeable if an intervening cause breaks the
    chain of causation.” 
    Id. at 1344
     (quoting Avery v. United States, 
    165 Ct. Cl. 357
    , 364-65,
    
    320 F.2d 640
    , 644-45 (1964) (internal quotations omitted)). Additionally, foreseeability “is
    not simply measured from the viewpoint of the government; foreseeability is an objective
    inquiry.” In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl.
    at 255.
    Plaintiffs argue that “the evidence established that the Bureau made a conscious
    decision on the night of February [sic] 12-13, 2013, to increase releases from Olympus
    Dam to as much as 6100 cfs,” when the Bureau knew from its Emergency Action Plan
    “that releases over 1500 cfs can cause flooding below, and releases of 6000 cfs cause
    most of the properties to be inundated, and there is also the possibility of loss of life.”
    (alteration added). Plaintiffs further argue that the Bureau increased releases through the
    Olympus Dam “to preserve a 1-foot buffer between the top of Lake Estes and the top of
    the spillway gates” and that the Bureau also “made the decision to reduce flows in the
    Olympus Tunnel from 550 cfs to 200 cfs,” necessitating the increased releases through
    Olympus Dam, “because the [Pole Hill] power plant was shutting down and it did not want
    to run the additional flows through the Pine Hill Rediversion Structure.” (alteration added).
    Plaintiffs also argue that “the same actions and decisions that benefitted and
    protected the government’s C-BT properties during the storm,” by not “allowing the
    elevation of Lake Estes to rise above 7474 feet” are the same “actions that caused takings
    of the Orr and Carman properties.” According to plaintiffs, “[d]amage to their properties
    was the direct result of the government’s construction and operation of its C-BT facilities.”
    (alteration added). Plaintiffs further argue that “‘[t]he court should determine here
    “whether the [flooding] on the claimants[‘] property was the predictable result of the
    government action.”’” (first alteration added) (quoting In re Upstream Addicks & Barker
    (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 254 (quoting Ridge Line, Inc. v. United
    States, 
    346 F.3d at
    1356 (citing Sanguinetti v. United States, 
    264 U.S. 146
    , 149-50
    (1924)))). According to plaintiffs, the government “knew its releases were likely to
    inundate and flood downstream properties,” and, therefore, the damages to plaintiffs’
    properties were “‘the natural consequences of the government’s actions.’” (quoting In re
    Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 255
    (internal quotations omitted)). Plaintiffs state that the foreseeability of the damages “is
    83
    true whether the court measures foreseeability in terms of only the Bureau’s 2013 storm
    event decisions and actions or over the entire period from when the C-BT and its facilities
    were conceived of, authorized, and built in the first half of the Twentieth Century.”
    Defendant argues that because of the historic storm, “[a]ny argument that the
    flooding of Plaintiffs’ properties was the direct, natural, or probable result of the Bureau’s
    releases fails because the historic storm and role of the North Fork Big Thompson River,
    as discussed above, sever any chain of causation.” (alteration added). Defendant also
    argues that “flooding fourteen to sixteen miles downstream could not benefit the Bureau,”
    and states that it “gained nothing—it appropriated nothing to its benefit—from any alleged
    additional flooding of Plaintiffs’ properties.” According to defendant, water from Olympus
    Dam would be joined by “[r]ainfall and runoff,” as well as the confluence of the North Fork
    Big Thompson River, before it reached plaintiffs’ properties, and “[t]his attenuated course
    of events undermines any ‘direct result’ argument.” (alterations added).
    As noted above, the Emergency Action Plan, which governed the operation of the
    Olympus Dam at the time of the September 2013 storm, provides that “it is at a flow of
    1,500 ft3/s in the Big Thompson River that water level first reaches the level of homes and
    businesses below Olympus Dam,” and further that “most structures in the Big Thompson
    Canyon below Olympus Dam are inundated at a flow of 6,000 ft3/s.” This guidance in the
    Emergency Action Plan indicates that the government was aware during the time of the
    September 2013 storm of approximately what levels of flow rate in the Big Thompson
    River would begin to cause certain amounts of flooding. Importantly, the Emergency
    Action Plan’s references to 1,500 cfs and 6,000 cfs refer to flow rate in the Big Thompson
    River, not to the flow rate of water being discharged from Olympus Dam. As the evidence
    in the record before the court indicates, the flow in the Big Thompson River near plaintiffs’
    properties had exceeded the flooding thresholds before the Bureau personnel operating
    Olympus Dam commenced peak releases at approximately 11:30 p.m. on September 12,
    2013. As indicated above, peak flow in the North Fork Big Thompson River above the
    confluence at Drake exceeded 7,000 cfs, meaning that even with no water in the Big
    Thompson River above Drake, the addition of the North Fork Big Thompson River alone
    would have caused the river near plaintiffs’ properties to exceed the flow rates at which
    properties would begin to flood. Moreover, the Bureau personnel studied and appear to
    have understood the severity of the storm as it was occurring at the relevant time. The
    Bureau personnel initiated the use of their Incident Management Procedures, including
    engaging in coordinating efforts with local government through Mr. VanShaar. As of the
    early morning hours of September 12, 2013, Bureau personnel were onsite at Olympus
    Dam, in the pouring rain, because the dam had to be operated manually.
    The damage to plaintiffs’ properties must be “‘the actual and natural consequence
    of the government act’” in order to support plaintiffs’ takings claims. See Moden v. United
    States, 
    404 F.3d at 1344
     (quoting Avery v. United States, 
    165 Ct. Cl. at 364-65
    ). When
    engaging in an “objective inquiry” into the foreseeability of plaintiffs’ damages, see In re
    Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 255, the
    higher flow rate in the North Fork Big Thompson River than in the Big Thompson above
    Drake, which at its peak exceeded 7,000 cfs, along with other potential sources of water
    such as heavy rainfall and runoff between the Olympus Dam and plaintiffs’ properties,
    84
    constituted “intervening cause” for plaintiffs’ property damage to “break[] the chain of
    causation” between the Olympus Dam releases and the damage to plaintiffs’ properties.
    See Moden v. United States, 
    404 F.3d at 1344
     (alteration added).
    As the evidence and testimony introduced at trial demonstrates, the government
    officials of the Bureau of Reclamation reviewed conditions at the Olympus Dam while they
    were occurring during the September 11, 12, and 13, 2013 weather events and acted to
    safely operate Olympus Dam during the September 2013 storm. As multiple government
    officials testified, Bureau of Reclamation staff were on duty, either remotely or at the dam
    site, continually from the outset of heavy rain in the late evening of September 11, 2013.
    Importantly, the water schedulers, Carlos Lora and Tim Miller, had to manage releases
    through Olympus Dam’s gates with one inoperable gate and no operable gauges
    upstream of Lake Estes to measure inflow. Also, uncontroverted testimony at trial
    described Lake Estes as “reactive” because of its shallow reservoir, in which the water
    elevation could rise or fall quickly. As Dr. Bowles testified, the consequences of
    overtopping portions of Olympus Dam could have been an uncontrolled release, or even
    a total failure of the dam. Without functioning upstream gauges or all spillway gates online,
    which were factors outside the Bureau of Reclamation’s control during the September
    2013 storm, the Bureau’s staff, nonetheless, were able to manage releases from Olympus
    Dam to keep Lake Estes in its operating range. Furthermore, the dam operators did not
    rapidly open all gates in order to preserve the dam but, as testimony from government
    officials demonstrates, they gradually increased releases to respond to increasingly
    heavy rainfall entering the reservoir via runoff beginning September 11 and throughout
    September 12, 2013. Moreover, the Bureau of Reclamation employees increased
    releases through Olympus Dam in order to prevent further damage to other structures of
    the C-BT system, including the damaged Pole Hill Powerplant and Little Hells Canyon
    Rediversion Structure, for which reason the Bureau had closed Olympus Tunnel and,
    thereby, the Bureau was left with fewer options to remove water from the Lake Estes
    reservoir. The conduct of Bureau of Reclamation officials does not evidence an intent to
    cause flooding downstream of Olympus Dam, but rather to maintain the dam and thereby
    stop additional flooding. The actions taken by the Bureau of Reclamation personnel
    during the September 2013 storm, therefore, had the foreseeable and actual effect of
    preserving Olympus Dam and averting the potentially more catastrophic consequences
    of dam failure to plaintiffs’ property. For these reasons, plaintiffs have not demonstrated
    the intent or foreseeability of damage to plaintiffs’ properties from the Bureau’s operation
    of Olympus Dam.
    Reasonable Investment-Backed Expectations
    Plaintiffs state that they “assert that this factor was intended to be applied only in
    regulatory claims,” but nevertheless address the factor as set out in Arkansas Game &
    Fish Commission v. United States, 
    568 U.S. at 39
    .56 Plaintiffs argue that “even when a
    person acquires property with actual notice of an ongoing taking or that a taking might
    occur in the future, the claim need not fail.” (emphasis in original) (citing In re Upstream
    56As discussed above, plaintiffs’ claims regarding the type of taking at issue in the above
    captioned case were confused.
    85
    Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 261). Plaintiffs further
    argue that “neither Ms. Orr nor the Carmans knew their properties would flood or be
    destroyed in a flood after the severe 1976 flood had passed through with a much larger
    amount of water and not washed away any properties.” Defendant responds, arguing that
    “Plaintiffs knew their properties could suffer damage from flooding by the Big Thompson
    River,” because “Plaintiffs knew that the Big Thompson River flowed next to their property
    [sic],” which “were on the downslope of a narrow canyon,” and because “the 1976 food
    similarly damaged Plaintiffs’ properties.” (alteration added).
    The reasonable investment-backed expectations prong of the Arkansas Game &
    Fish Commission analysis is distinct from the intent and foreseeability component of that
    analysis. While intent and foreseeability consider the actions of the government and
    whether they led to the alleged taking, the reasonable invest-backed expectations
    analysis considers the character of plaintiffs’ land. In the Arkansas Game & Fish
    Commission context, courts have considered the susceptibility of the property to flooding
    prior to the alleged taking. See Arkansas Game & Fish Comm’n v. United States, 
    568 U.S. at 39
     (“For example, the Management Area lies in a floodplain below a dam, and
    had experienced flooding in the past.”); In re Upstream Addicks & Barker (Texas) Flood-
    Control Reservoirs, 146 Fed. Cl. at 261 (“In this case, properties are located in a
    geographical area that is generally susceptible to large storms and potential flooding.”).
    Plaintiffs’ testimony and the evidence in the record before the court indicate that
    when the September 2013 flood occurred, the last flood to damage plaintiffs’ properties
    had occurred in 1976. As stipulated by the parties and testified to at trial, the plaintiffs
    held fee simple ownership of their properties beginning in 1976. As a result, for
    approximately the entire time that plaintiffs owned their property up to the time of the
    September 2013 storm, about 37 years, the plaintiffs had enjoyed their property with only
    one serious flood. Moreover, the witnesses at trial testified that the Big Thompson River
    is ordinarily a small, quiet river with a low flow rate, typically between 50 and 75 cfs, and
    shallow enough in most places that, as Mr. VanShaar testified, “you could walk across it.”
    As Mr. and Mrs. Carman testified, however, they were aware at the time they purchased
    their property, following the 1976 flood, that the property “may be located and situate in a
    flood plain,” and the Carmans did not construct any permanent structures on the portion
    of their property closest to the Big Thompson River. Although plaintiffs might reasonably
    not have been acutely concerned about a flooding on their property, given the riverside
    location of their property, the upstream dam and the always unpredictable weather,
    plaintiffs’ expectations that their property would be flood-free in the future could not have
    been totally secure. Regardless, given the above discussion on causation and intent or
    foreseeability, success on this factor alone, even if established by plaintiffs, would not
    establish a taking for the Carman and Orr properties.
    Severity
    Plaintiffs argue that “‘even a single flooding event may give rise to a taking
    where the defendant uses a permanent structure to “purposely flood[] a property once
    and expressly reserves the right to do so in the future.”’” (emphasis and alteration in
    original) (quoting In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146
    86
    Fed. Cl. at 250 (quoting Quebedeaux v. United States, 
    112 Fed. Cl. at 323
    )). According
    to plaintiffs, the “flooding caused devaluation of their properties, destruction of their real
    and personal property, and displacement from their homes and businesses for an
    extended period,”57 as the September 2013 flood destroyed the Carmans’ home and
    business and part of Ms. Orr’s home and property, “along with the personal property in
    the Orr and Carman homes.” The September 2013 flood, according to plaintiffs, led to
    “the State of Colorado’s determination that in rebuilding after the flood it required their
    [the Carmans’] property to re-route the highway,” and “involved 0.63 acres of Ms. Orr’s
    land that has been permanently washed away.” (alteration added).
    Defendant argues, however, against the severity factor of plaintiffs’ taking
    allegations, claiming that plaintiffs “remained free to use, access, or enjoy ownership of
    their properties,” as demonstrated by the fact that “the Carmans sold their properties to
    the Colorado Department of Transportation after the storm,” and Ms. Orr’s “land has been
    reclaimed and filled in, and is no longer under water.” (citing Cary v. United States, 
    552 F.3d 1373
    , 1380 (Fed. Cir. 2009)).
    The Supreme Court of the United States in Pumpelly v. Green Bay & Mississippi
    Canal Co., 
    80 U.S. (13 Wall.) 166
    , explained “that where real estate is actually invaded
    by superinduced additions of water, earth, sand, or other material, or by having any
    artificial structure placed on it, so as to effectually destroy or impair its usefulness, it is a
    taking” under the Fifth Amendment to the United States Constitution. See 
    id. at 181
    ; see
    also Ark. Game & Fish Comm’n v. United States, 
    568 U.S. at
    32 (citing Pumpelly v. Green
    Bay & Miss. Canal Co., 80 U.S. (13 Wall.) at 177); Sanguinetti v. United States, 
    264 U.S. at 148
     (quoting Pumpelly v. Green Bay & Miss. Canal Co., 80 U.S. (13 Wall.) at 181);
    Vaizburd v. United States, 
    384 F.3d 1278
    , 1282 (Fed. Cir. 2004) (“Government action
    that causes sand accretion, flooding, or accumulation of other materials on a landowner’s
    property may constitute a physical taking.” (citing Pumpelly v. Green Bay & Miss. Canal
    Co., 80 U.S. (13 Wall.) at 181)).
    A Judge of the United States Court of Federal Claims in Ideker Farms, Inc. v.
    United States, 
    151 Fed. Cl. 560
     (2020), appeal filed, Nos. 21-1849, 21-1875 (Fed. Cir.
    Apr. 22, 2021), explained that to analyze the severity of an alleged taking, “the court must
    determine whether or not ‘the asserted intrusion was within a range that the property
    owner could have reasonably expected to experience in the natural course of things.’” Id.
    at 584 (quoting Ark. Game & Fish Comm’n v. United States, 
    736 F.3d at 1375
    ). Moreover,
    in the In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs case, another
    Judge of the Court of Federal Claims held that “intermittent inundation of land, as
    contrasted to continuous overflow, can give rise to a viable permanent taking claim,” In
    re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 250
    (citing United States v. Cress, 
    243 U.S. at 328
    ), and that “the fact that property has been
    or could be, with sufficient outlays, restored to its pre-flood condition is not a relevant
    57The court has not accepted any general indication by plaintiffs that Ms. Orr and Mr. and
    Mrs. Carman lost all of their real and personal property at their respected parcels of land
    during the September 2013 storm, such as by plaintiffs’ allegation of the “destruction of
    their real and personal property,” without qualification.
    87
    consideration in the severity analysis.” 
    Id.
     at 252-53 (citing Ark. Game & Fish Comm’n v.
    United States, 
    568 U.S. at 26-34
    ; United States v. Dickinson, 
    331 U.S. 745
    , 751 (1947)).
    Plaintiffs in the above captioned case testified at trial that they lost their homes and
    personal property as a result of the flooding that occurred during the September 2013
    storm. The Carmans additionally testified that they lost their business and their horses
    because of the damage done to their property by the flooding. As defendant points out,
    Ms. Orr appears to have reclaimed her property from the riverbed, as plaintiffs’ expert Mr.
    Potter’s post-flood graphic, based on a Google Earth image from 2019, appears to show
    land on Ms. Orr’s property, which had been flooded, filled in. As defendant also points
    out, the Carmans sold their land to the Colorado Department of Transportation for the
    relocation of Highway 34. The court notes, however, that demonstrating “accretion,
    flooding, or accumulation of other materials” can be sufficiently severe to support a taking,
    see Vaizburd v. United States, 
    384 F.3d at 1282
    , as is having property “actually invaded
    by superinduced additions of water, earth, sand, or other material,” Pumpelly v. Green
    Bay & Mississippi Canal Co., 80 U.S. (13 Wall.) at 181. Similarly, selling or attempting to
    improve the property in the wake of a flood or other destruction of one’s property does
    not necessarily diminish the severity of the damage experienced. See In re Upstream
    Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 252-53 (“[T]he fact
    that property has been or could be, with sufficient outlays, restored to its pre-flood
    condition is not a relevant consideration in the severity analysis.” (alteration added)).
    The above analysis demonstrates that, by an application of the framework set forth
    in the United States Supreme Court’s Arkansas Game & Fish Commission decision,
    plaintiffs in the above captioned case perhaps might have been able to demonstrate that,
    because plaintiffs lost property in the September 2013 storm, the alleged harm due to the
    flooding was severe. At trial, however, although plaintiffs each described their losses, no
    independent evidence on valuation was offered. Moreover, as discussed above, plaintiffs
    have failed to carry their burden with respect to establishing that the Bureau of
    Reclamation’s actions caused the loss of plaintiffs’ properties, that the flooding of
    plaintiffs’ properties was an intentional or the foreseeable result of the government’s
    actions, or that the flooding attributable to the government was of sufficient duration to
    constitute a taking.
    Necessity Doctrine
    Defendant also argues that the United States “is not liable for destruction of real
    and personal property when, in the case of actual necessity, the government acts to
    prevent grave threats to life and property.” (citing TrinCo Inv. Co. v. United States, 
    722 F.3d 1375
    , 1377 (Fed. Cir. 2013)). Defendant cites the analysis of defendant’s expert Dr.
    David Bowles, which, as explained above, “assessed three hypothetical cases” of limiting
    releases from Olympus Dam starting at 2:15 a.m. on September 12, 2013, and continuing
    for the duration of the September 2013 storm, which differed from the actions taken by
    the Bureau during the September 2013 storm. Dr. Bowles explained the potential
    consequences of overtopping the spillway gates of Olympus Dam in his expert report and
    at trial, testifying regarding potentially jamming the “lifting arms” of the gates and the gates
    “peel[ing] away” from the dam; exceeding the sliding stability threshold, which would
    88
    “propagate[] a crack underneath the dam” because of which “you’d no longer have the
    dam secured to the ground;” overtopping the left abutment of Olympus Dam, which could
    “erode out the toe of the dam” and “potentially eat through the dam;” and overtopping the
    parapet wall of Olympus Dam, which has “the potential to initiate an erosional failure” at
    the right end of Olympus Dam. (alterations added). Defendant asserts that “in each
    hypothetical, Olympus Dam would suffer radial gate overtopping, the potential for
    concrete sliding failure, and the potential for erosional failure.”
    Defendant argues that the doctrine of necessity, which “requires ‘an imminent
    danger and an actual emergency giving rise to actual necessity,’”58 applies to plaintiffs’
    case. (quoting TrinCo Inv. Co. v. United States, 
    722 F.3d at 1378
    ). According to
    defendant, when “determining whether a response is necessary, the proper focus is on
    whether it was reasonable under the circumstances.” (citing the decision after remand in
    Trin-Co Inv. Co. v. United States, 
    130 Fed. Cl. 592
    , 599-600 (2017)). Defendant further
    argues that “‘the necessity of an “actually necessary” [sic] response[] must be measured
    at the time of the actual emergency and imminent danger, not in hindsight,’” (emphasis in
    original; first alteration added) (quoting Trin-Co Inv. Co. v. United States, 
    130 Fed. Cl. at 601
     (quoting Brewer v. State, 
    341 P.3d 1107
    , 1118 (Alaska 2014))), and defendant
    argues that “this assessment must consider the information available at the time.”
    Defendant, quoting the trial testimony of Paula O’Brien, emphasizes that Lake
    Estes is “a ‘sensitive reservoir’ with ‘very little storage’ that is ‘very reactive to inflows,’”
    and that “Lake Estes rose to within mere inches of the top of the operational pool by the
    evening of September 12,” after “the Bureau had been facing a steadily increasing
    elevation level for twenty-four hours despite its releases,” while “estimated inflow was
    increasing by 1,000 cfs hour over hour—threatening to engulf the buffer space and
    overtop the radial gates.” Moreover, defendant argues that “[w]hile Bureau employees
    58Defendant previously asserted that the police powers doctrine also applies in the above
    captioned case as a defense to the government’s liability. Defendant refers to the police
    powers defense only in a footnote to the necessity defense in its trial brief, however,
    arguing that “[b]ecause the United States acted reasonably when faced with an
    unavoidable choice involving health, safety, and public welfare, its actions are similarly
    insulated from takings liability.” (alteration added). Plaintiffs opposed defendant’s
    assertion of the police powers defense on the grounds that the
    decisions by the Bureau, the same ones that ultimately caused the taking,
    created the purported emergency the United States now seeks to use to
    invoke as the impetus for its police powers defense. The Court should reject
    that defense since a party cannot manufacture an emergency and then use
    it as an excuse for its unlawful acts to correct the emergency it created.
    (citing In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl.
    at 263-64). Defendant’s police powers defense, however, was not fully developed by the
    parties and is not necessary to the court’s decision in the above captioned case, in which
    the court has found causation of the damage to plaintiffs’ property is not attributable to
    the defendant and that no taking occurred in the above captioned case.
    89
    have said that Olympus Dam was safe during the storm, those comments do not diminish
    the imminent danger. Defendant argues that Bureau employees believed Olympus Dam
    was not in danger of breaching or failing because of the Bureau’s operations,” (alteration
    added), and defendant cites the testimonies of Bureau of Reclamation employees James
    VanShaar, Ralph Beall, and Paula O’Brien, all of whom testified that the Bureau of
    Reclamation employees’ actions during the September 2013 storm prevented Olympus
    Dam from being in danger or damaged. Defendant claims that “the Bureau’s success in
    averting dam failure does not negate the imminent danger.”
    Defendant also argues “that the September 2013 storm created an actual
    emergency,” recognized when “the state of Colorado, the federal government, and the
    city of Loveland all declared the storm an emergency before inflow to Lake Estes or its
    elevation level had even peaked,” and when “[t]he Bureau formed an Incident
    Management Team during the storm, which it uses to manage ‘emergencies at Olympus
    Dam.’” (emphasis in original; alteration added). Defendant states that the September
    2013 storm had an “annual exceedance probability” of “as low as 0.1%,” or “a 1,000-year
    storm event,” in which, during a twenty-four-hour period, “Estes Park received more than
    double its September monthly average rainfall.”59
    According to defendant, “the Bureau’s actions in releasing water from Olympus
    Dam were reasonably necessary because of the increasing elevation of Lake Estes and
    the ongoing severe nature of the storm.” Defendant asserts that plaintiffs cannot rely on
    “the benefit of hindsight” to argue over “what the Bureau could or should have done,” but
    instead contends that with the information the Bureau had, indicating that “the Bureau
    projected the storm to continue, with estimates of inflow increasing by 1,000 cfs hour over
    hour,” the court should find that “the Bureau’s actions were reasonably necessary in
    response to the imminent danger of dam failure and the actual emergency of the 1,000-
    year storm event.” Defendant distinguishes the above captioned case from the Upstream
    Addicks case decided by a Judge of the Court of Federal Claims.60 Defendant argues that
    “the Bureau did not design Olympus Dam to impound water on Plaintiffs’ properties,” and
    the government did not cause the flooding of plaintiffs’ properties “as ‘the direct result of
    calculated planning.’” (citing In re Upstream Addicks & Barker (Texas) Flood-Control
    Reservoirs, 146 Fed. Cl. at 264). Defendant instead characterizes the flooding as “just an
    incidental effect” of responding to the emergency.
    59 Defendant cites to the rainfall “[f]rom the early morning of September 12 through the
    early morning of September 13—a period that include peak inflow at Lake Estes,”
    although defendant does not state the amount of rainfall that fell during that twenty-four-
    hour period. Defendant also claims that Estes Park “received 11.54 inches of rain
    between September 9 and September 16.”
    60Defendant also cites to In re Downstream Addicks and Barker (Texas) Flood-Control
    Reservoirs, 
    147 Fed. Cl. 566
    , 575-76 (2020), to support its argument, however, the
    Downstream Addicks decision was reversed and remanded by the Federal Circuit in
    Milton v. United States, 36 F.4th at 1163, after all submissions by the parties were
    completed in the case currently before this court.
    90
    As noted above, defendant’s witness Dr. Bowles considered three hypothetical
    scenarios in which water releases from the Olympus Dam remained static throughout the
    September 2013 storm. Dr. Bowles calculated, for each hypothetical, the duration of time
    that different portions of the Olympus Dam would have been overtopped or damaged.
    Plaintiffs, however, argue that defendant’s expert witness Dr. Bowles’ conclusion that
    Olympus Dam was in danger during the September 2013 storm is not credible. Plaintiffs
    argue that Bureau of Reclamation personnel Howard Bailey and Paula O’Brien testified
    “that Olympus Dam was never in danger of failing or breaching” during the storm. Plaintiffs
    quote extensively from the testimonies of these witnesses, including Mr. Bailey’s
    statement, when asked how he knew that “Olympus Dam was not in danger:”
    I know this because we had people on site at the dam and because I was
    attending all the Incident Management Team meetings and other
    reoccurring meetings where we were receiving feedback from the people
    on site. And at no point was there any failure or breach suggested. We were
    constantly concerned with the safety of the dam. And in the extensive onsite
    monitoring that was being done, the team was consistently assured that the
    dam was not at risk of failing.
    As quoted by plaintiffs, Ms. O’Brien’s testimony differentiated the “long-term risk” of
    Olympus Dam overtopping if releases were not made, from the lack of “active present
    tense” danger of Olympus Dam failing during the September 2013 storm.
    Plaintiffs argue that defendant’s expert Dr. Bowles did not consider the Olympus
    Dam Emergency Action Plan in formulating his hypothetical scenarios of dam failure, nor
    did Dr. Bowles consider “maintaining an elevation below 7474 feet and then following the
    Emergency Action Plan or restricting releases to less than 1500 cfs” in his hypothetical
    scenarios. Plaintiffs state that “Dr. Bowles admitted on cross-examination that his
    hypothetical scenarios could never have occurred if the elevation of Lake Estes never
    exceeded 7475 feet,” the overtopping height of Olympus Dam’s spillway gates when
    closed. Plaintiffs argue that “the elevation of Lake Estes never even reached (let alone
    exceeded) 7474 feet” during the September 2013 storm. Plaintiffs further argue that Dr.
    Bowles’ hypothetical scenarios of the dangers of exceeding 7,475 feet elevation in Lake
    Estes are inconsistent with the historic “first fill” of Olympus Dam, which the Bureau’s Post
    Incident Analysis Report records as 7,475.25 feet. For these reasons, plaintiffs argue that
    defendant’s expert Dr. Bowles’ opinions on the safety of Olympus Dam are not credible.
    Additionally, plaintiffs argue that defendant’s necessity defense fails because “‘the
    government is responsible for creating the emergency,’” and the government knew that
    “‘flooding beyond the extent of government-owned land upstream would result, in light of
    the design of the dams and the plans for their operation.’” (quoting In re Upstream Addicks
    & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 264). Plaintiffs argue in their
    reply brief that the Bureau’s decisions, including, according to plaintiffs, “releasing more
    water than necessary in order to draw down the elevation of Lake Estes,” and “shutting
    down the Olympus Tunnel,” “were made to protect government properties in the C-BT,”
    and that the Bureau made those decisions “knowing its releases would inundate
    properties downstream.” Therefore, according to plaintiffs, “‘the necessity defense cannot
    91
    apply here, because it cannot be said that “necessity” existed in this case, when the
    flooding that occurred was the direct result of calculated planning,’” as well as “the
    Bureau’s decisions in running its C-BT facilities during the 2013 storm.” (quoting In re
    Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 264).
    As the United States Court of Appeals for the Federal Circuit explained the
    necessity doctrine in TrinCo Investment Co. v. United States,
    the United States Supreme Court has observed that the “common law ha[s]
    long recognized that in times of imminent peril—such as when fire
    threatened a whole community—the sovereign could, with immunity,
    destroy the property of a few that the property of the many and the lives of
    many more could be saved.”
    TrinCo Inv. Co. v. United States, 
    722 F.3d at 1377
     (alteration in original) (quoting United
    States v. Caltex, 
    344 U.S. 149
    , 154 (1952)). The necessity doctrine absolves the
    government of liability for the property it destroys in responding to the emergency. See
    
    id.
     (quoting Lucas v. S.C. Coastal Council, 
    505 U.S. 1003
    , 1029 n.16 (1992)). Moreover,
    the Federal Circuit has stated that “the doctrine of necessity may be applied only when
    there is an imminent danger and an actual emergency giving rise to actual necessity.” 
    Id.
    (citing United States v. Caltex, 344 U.S. at 151-56; Ralli v. Troop, 
    157 U.S. 386
    , 405
    (1895); Bowditch v. City of Boston, 101 U.S. (11 Otto) 16, 16-19 (1879); Mitchell v.
    Harmony, 
    54 U.S. (13 How.) 115
    , 135 (1851)). The Judge of the Court of Federal Claims
    in Upstream Addicks restated the rule from TrinCo as: “Three requirements must be met
    for the necessity doctrine to apply: (1) ‘actual emergency;’ (2) ‘imminent danger;’ and (3)
    ‘actual necessity of the [g]overnment action.’” In re Upstream Addicks & Barker (Texas)
    Flood-Control Reservoirs, 146 Fed. Cl. at 264 (alteration in original) (quoting TrinCo Inv.
    Co. v. United States, 
    722 F.3d at 1379
    ). The Upstream Addicks court, moreover,
    acknowledged limits on the necessity doctrine:
    Where, as here, the government is responsible for creating the emergency,
    granting the government immunity from liability under the necessity doctrine
    would “stretch[ ] the doctrine too far.” [TrinCo Inv. Co. v. United States, 
    722 F.3d at 1378
    ]. Further, the term “emergency,” according to both common
    usage and definition, refers to “a state of things unexpectedly arising.”
    Emergency,                Oxford               English               Dictionary,
    https://www.oed.com/view/Entry/61130?redirectedFrom=emergency#eid
    (last visited Dec. 17, 2019) (emphasis added).
    In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146 Fed. Cl. at 264
    (emphasis and first alteration in original). The Judge in Upstream Addicks refused to apply
    the necessity defense based on these limitations, because “the Corps knew that when a
    severe storm like Harvey came, flooding beyond the extent of government-owned land
    upstream,” and because the government created the emergency when it “made a
    calculated decision years before Harvey, when it designed, modified, and maintained the
    dams in such a way that would flood private properties during severe storms.” Id. at 263-
    64.
    92
    As discussed above, the evidence in the record before this court in plaintiffs’ case
    indicates that September 2013 flood was the first significant flood since 1976 in the Big
    Thompson River Canyon. Plaintiffs testified that on the morning of September 12, 2013,
    they received automated “reverse 911” calls to their homes advising them to evacuate.
    By the time of the “reverse 911” calls, the Bureau personnel at Olympus Dam and the
    East Colorado Area Office had already begun to activate their emergency response
    procedures, such as the activation of the Incident Management Team in the early morning
    hours of September 12, 2013, and the initiation of emergency alerts up to Response Level
    3, and the Bureau’s response to the September 2013 flood began the night before, on
    September 11, 2013. Additionally, on September 12, 2013, the federal government, the
    State of Colorado, and the City of Loveland all declared emergencies in response to the
    September 2013 storms. This does not indicate a lack of responsiveness by the Bureau,
    but rather that the magnitude of the September 2013 storm and the flooding and
    consequences it could cause were unexpected from the perspectives of the federal
    government and the state and local officials, as well as plaintiffs. Therefore, the reasoning
    of the Upstream Addicks case does not control in the above captioned case because,
    under the definition of “emergency” utilized by the In re Upstream Addicks & Barker
    (Texas) Flood-Control Reservoirs Judge, the September 2013 storm in the above
    captioned case represented “a state of things unexpectedly arising” which Bureau
    personnel then took steps to address. See Emergency, Oxford English Dictionary,
    https://www.oed.com/view/Entry/61130?redirectedFrom=emergency#eid (last visited
    May 2, 2023); In re Upstream Addicks & Barker (Texas) Flood-Control Reservoirs, 146
    Fed. Cl. at 264.
    Moreover, and as discussed above, the evidence in the record before the court
    does not establish that the Bureau’s operation of Olympus Dam caused the flooding which
    damaged plaintiffs’ properties. Furthermore, under the standards articulated in Arkansas
    Game & Fish Commission v. United States, 
    568 U.S. 23
    , given the data contained in the
    Colorado Department of Transportation 2014 Hydrology Report, even with a bulking
    factor of 2.0, the largest suggested by plaintiffs’ expert Mr. Brown, the peak release from
    Olympus Dam would have accounted for only 1,444 cfs of the peak flow in the Big
    Thompson River at plaintiffs’ homes, out of more than 14,000 cfs. As found above, the
    flooding at plaintiffs’ properties and throughout the Big Thompson River Canyon was not
    a direct product of the actions of the Bureau of Reclamation.
    Federal, state, and local authorities all declared emergencies with respect to the
    Big Thompson River Canyon area on September 12, 2013, in response to the ongoing
    storm. The Bureau personnel operating Olympus Dam and the East Colorado Area Office
    activated their emergency procedures and formed an Incident Management Team. During
    the course of September 12, rainfall and runoff from the storm increased, while C-BT
    Project facilities such as the Pole Hill Powerplant began to suffer damages from the
    sudden influx of floodwaters, resulting in the Bureau personnel seeking alternate methods
    of moving water through the system to avoid further damage to facilities while more water
    continued to enter the system. Over the course of the night of September 12 into 13,
    2013, water levels continued to rise in Lake Estes, ultimately coming very close to the top
    of the operational pool in Lake Estes at elevation 7,474 feet, as testified by Mr. Miller. It
    may appear, based on the understanding of certain government officials that the Olympus
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    Dam was not in imminent danger, which conflicted with testimony by other government
    officials indicating that a “danger” or “risk” was posed by the rising water elevations, and
    which resulted, after consideration, in a decision to effect increased water releases to
    avoid what they considered more catastrophic damages. The steps taken by the
    government officials, however, according to their own testimony, were ultimately the
    reason that the Olympus Dam did not fail, which was the danger that concerned them.
    The testimony that the dam was not in danger can also be understood as reflecting that
    those witnesses understood that it was their own success given that the actions they took
    preserved the dam, not a lack of a possibility that the dam could fail, including by Paula
    O’Brien’s contrast of “risk” and “danger” in her testimony. The court found the testimony
    from the Bureau employees who testified to the actions taken as part of the response to
    the September 2013 storm to be credible. The actions of the government officials and
    personnel on September 12 to treat the September 2013 storm as an unpredictable
    emergency in an extreme weather situation, especially the continuing and intensifying
    rainfall and runoff from the storm, leading to floodwaters which damaged C-BT Project
    facilities, indicate that on September 12, 2013, the storm represented an actual
    emergency within the meaning of the necessity doctrine. See TrinCo Inv. Co. v. United
    States, 
    722 F.3d at 1379
    .
    Moreover, during the night of September 12 and 13, 2013, rainfall and runoff from
    the storm continued to enter Lake Estes at a high rate, causing the water level in Lake
    Estes to rise. The Bureau personnel, however, lacked a method to accurately measure
    the inflow in Lake Estes and outflow from Olympus Dam, as the downstream gauge had
    been inoperable since early in the morning of September 12, and had to rely on
    calculations based on Olympus Dam spillway gate openings and Lake Estes reservoir
    elevations. By approximately 11:30 p.m. on the night of September 12, the water elevation
    in Lake Estes was less than half a foot below the 7,474 feet height of the top of the
    operational pool, and if the water rose above the top of the operational pool, there was
    only one further foot of vertical space in Lake Estes before the water would overtop the
    closed Gate 3 on the Olympus Dam spillway. As Dr. Bowles testified, the overtopping of
    one or more of the spillway gates could have led to failure of the Olympus Dam and
    uncontrolled releases downstream into the Big Thompson River. Because the Bureau
    personnel found themselves with so little storage space left in the Lake Estes reservoir,
    while the storm continued to deposit more and more rainfall and runoff into Lake Estes,
    by shortly before midnight, September 12, 2013, it was reasonable to conclude that there
    was imminent danger to Olympus Dam within the meaning of the necessity doctrine. See
    TrinCo Inv. Co. v. United States, 
    722 F.3d at 1379
    .
    While plaintiffs argue that the Bureau could have waited longer before it began its
    peak releases, increased its releases less, or could have opened Olympus Tunnel to
    allow more water to leave Lake Estes other than through Olympus Dam, plaintiffs’ after-
    the-fact arguments do not overcome the conclusions reached by the government officials
    at the time, including at the Olympus Dam site, to prevent more catastrophic damage and
    the necessity of the government’s actions. The Bureau personnel operating Olympus
    Dam at the time that peak releases were commenced from Olympus Dam did not have
    access to the calibrated models of rainfall, runoff, and other storm features of which both
    parties have made use in after-the-fact analyses. Rather, Bureau personnel operated
    94
    during an emergency, without the ability to know whether the inflow to Lake Estes would
    increase or stabilize, and, therefore, Bureau personnel could not know with precision how
    long it would take to overtop Gate 3 if they did not increase releases as they ultimately,
    after consultation and deliberation, did. Further, the Bureau had already shut down inflow
    into the Eastern Slope portion of the C-BT Project through the Adams Tunnel, and so the
    Bureau was limited as to the actions it could take to control inflow to Lake Estes as rainfall
    increased. Additionally, the Bureau had stopped outflows through Olympus Tunnel in
    order to protect the failing Pole Hill Powerplant and the Rediversion Structure, which
    would have been in danger if the Bureau of Reclamation had reopened the Olympus
    Tunnel. Therefore, the Bureau personnel were faced with decisions without a crystal ball
    as to future storm conditions and the potential of causing damage to failing C-BT Project
    facilities. The government officials chose a reasonable security option under the
    circumstances when they increased releases through Olympus Dam sufficient to lower
    the water elevation in Lake Estes and give the Bureau personnel the ability to continue
    managing inflows into Lake Estes for the duration of the storm. Accordingly, there was a
    basis at the time for the government officials to conclude that it was necessary for the
    Bureau to increase releases from Olympus Dam shortly before midnight on the night of
    September 12 and 13, 2013. Therefore, also based on the necessity doctrine, plaintiffs
    cannot pursue a taking of plaintiffs’ properties resulting from the flooding which occurred
    during the September 2013 storm.
    CONCLUSION
    After reviewing the evidence in the record in the above captioned case, including
    the trial testimony, plaintiffs failed to establish that the United States caused the damage
    to plaintiffs’ properties during the September 2013 storm or that even if causation could
    have been established by the plaintiffs, that the doctrine of necessity would not apply to
    defeat plaintiffs’ claims. Accordingly, plaintiffs have failed to prove they have a takings
    claim under the Fifth Amendment to the United States Constitution. The Clerk of the Court
    shall enter JUDGMENT in favor of defendant.
    IT IS SO ORDERED.
    s/Marian Blank Horn
    MARIAN BLANK HORN
    Judge
    95