Halligan Water Supply Project draft environmental impact statement published

Posted on: Nov-22-2019

[Released by the U.S. Army Corps of Engineers Nov. 22, 2019]

The U.S. Army Corps of Engineers, Omaha District has published in the federal register the Draft Environmental Impact Statement and conceptual mitigation plan for the Halligan Water Supply Project, a water supply project located in Larimer County, Colorado, proposed by the City of Fort Collins Utilities.  

The Corps is evaluating an application and conceptual mitigation plan from Fort Collins for a Department of the Army permit for the Halligan Project and prepared the Draft EIS in accordance with the National Environmental Policy Act to provide decision-makers and the public with information pertaining to the Halligan Project and disclose environmental impacts of the alternatives.  It also provides information for local and state agencies having jurisdictional responsibility for affected resources.  The U.S. Environmental Protection Agency Region VIII, U.S. Fish and Wildlife Service, Bureau of Land Management, Colorado Department of Natural Resources, Colorado Department of Public Health and Environment, and Larimer County participated as cooperating agencies in the development of the Draft EIS.  The Corps is neither a proponent nor an opponent of the proposed project.  

Fort Collins proposes to enlarge the existing Halligan Reservoir located about 25 miles northwest of Fort Collins on the North Fork of the Poudre River in Larimer County, Colorado.  Fort Collins proposes to raise Halligan Dam by 25.4 feet to enlarge Halligan Reservoir from its current capacity of 6,400 acre-feet to approximately 14,525 acre-feet to provide about 7,900 acre-feet of additional annual firm yield to meet Fort Collins’ projected 2065 municipal and industrial water demands.  The existing reservoir surface area is approximately 253 acres; the proposed enlargement would result in a surface area of approximately 386 acres.

Halligan Dam is a concrete arch dam built more than 100 years ago and will require rehabilitation in the near future to address safety risks.  These safety risks would be addressed by Fort Collins under their proposed action during enlargement of the dam.  Under the project alternatives, ownership of the dam and responsibility for rehabilitation would revert to the North Poudre Irrigation Company.

Under Fort Collins’ proposed action, Halligan Reservoir would continue to be filled with direct flows from the North Fork.  Releases would be made to the North Fork downstream of the dam and would flow through Seaman Reservoir to the confluence with the Cache la Poudre River.  From there, water would be exchanged up to Fort Collins’ intake or to the Monroe Canal intake and delivered to Fort Collins’ water treatment facility through the Pleasant Valley Pipeline.  

Under the proposed action, Fort Collins would maintain a minimum flow of five cubic feet per second in the North Fork from May 1 to September 30, a minimum flow of three cubic feet per second the remainder of the year, and forego all diversions to the enlarged Halligan Reservoir for the three days that coincide with the forecasted peak runoff flow event for the North Fork.

The Draft EIS also evaluates the effects of several alternatives to Fort Collins’ proposed action, including the No-Action Alternative, the Expanded Glade Alternative, the Gravel Pits Alternative, and the Agricultural Reservoirs Alternative.

The Corps’ decision on whether or not to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts, of the proposed project and its alternatives on the public interest.  The decision will reflect the national concern for both protection and use of important resources.  The benefits that may reasonably be expected to accrue from the proposal must be balanced against the reasonably foreseeable detriments.  All factors that may be relevant to the proposal will be considered including the cumulative effects thereof; among those are conservation, economics, aesthetics, wetlands, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, energy needs, safety, food and fiber production, mineral needs, considerations of property ownership and, in general, the needs and welfare of the people.  

The Draft EIS and conceptual mitigation plan are available for review on our website at:  https://www.nwo.usace.army.mil/Missions/Regulatory-Program/Colorado/EIS-Halligan

Printed copies of the Draft EIS are available for review at the following libraries and offices:

• Colorado State University Morgan Library, 1201 Center Avenue, Fort Collins, Colorado 80523
• Poudre River Public Library District-Old Town Library, 201 Peterson Street, Fort Collins, Colorado 80524
• Poudre River Public Library-Harmony Library, 4616 South Shields Street, Fort Collins, Colorado 80526
• University of Northern Colorado, James A. Michener Library, 14th Avenue and 20th Street, Greeley, Colorado 80639
• U.S. Army Corps of Engineers, Denver Regulatory Office, 9307 South Wadsworth Boulevard, Littleton, Colorado 80128

The Corps is soliciting written comments on the Draft EIS and conceptual mitigation plan from the public; federal, state, and local agencies and officials; Native American Tribes; and other interested parties.  

On January 13, 2020, the Corps is holding a public hearing regarding the Department of the Army Permit application and Draft EIS for the Halligan Project. The public hearing will be at the Drake Centre at 802 West Drake Road in Fort Collins, Colorado.  From 5:30 to 7:00 p.m., the public may view various posters on the issues and ask questions of representatives of the U.S. Army Corps of Engineers, their contractors, and Fort Collins.  From 7:00 to 8:30 p.m., public officials or individuals wishing to make a public statement to the Corps will be given three minutes each to speak.

All written comments on the Draft EIS and conceptual mitigation plan must be submitted to the mailing address listed below or to email address NWO.HalliganEIS@usace.army.mil by January 26, 2020. Additional information about the application, Draft EIS, or conceptual mitigation plan may be obtained by contacting Mr. Cody Wheeler, Regulatory Project Manager at the U.S. Army Corps of Engineers, Denver Regulatory Office, 9307 South Wadsworth Boulevard, Littleton, Colorado 80128; at telephone 720-922-3846; or via email at cody.s.wheeler@usace.army.mil.

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