Gross Reservoir Expansion Project

Document library

Project specific plans

Denver Water has worked with stakeholders to develop, review and finalize various project related plan. Links to those final approved plans can be found here (due to file size they are shared through an external site). As additional plans receive final approval, they will be added to the list below and provided at the link above.

Federal Preemption Lawsuit

On July 14, 2021, Denver Water filed a lawsuit in U.S. District Court against Boulder County, asserting the county is overreaching its authority and jeopardizing a federally ordered reservoir expansion critical to a safe and secure water supply for one quarter of the state’s population while risking long-planned benefits for the West Slope environment.

Federal NEPA Lawsuit

In late 2018, groups opposing the Gross Reservoir Expansion Project filed suit against the U.S. Army Corps of Engineers and the U.S. Fish & Wildlife Service in opposition to the 404 Permit and Record of Decision that Denver Water received in July 2017. Denver Water intervened as a respondent and is defending the permit alongside the federal respondents. Below are the primary court filings in order of submittal.

Federal Energy Regulatory Commission Order

In July 2020 the Federal Energy Regulatory Commission issued an order to proceed with design and construction to expand Gross Reservoir in Boulder County. The order can be found below.

Final Federal Energy Regulatory Commission Hydropower License Amendment Application

Feb 2019: FERC published the Final Supplemental Environmental Assessment, including the Finding of No Significant Impact. 

Feb 2018: FERC published notice of availability of a Supplemental Environmental Assessment. Public comment will be accepted until April 9, 2018; instructions may be found here.

May 2017: We responded to public comments received by FERC during their 60-day comment period. Those responses can be found here.

April 2017: We provided FERC with details about our consultation with the U.S. Forest Service regarding changes to our Recreational Management Plan.

March 2017: We responded to FERC’s February 2017 request for more information with this letter.

February 2017: FERC notified Denver Water that the public comment period has started on our application to amend our hydropower license. They also wrote us a letter requesting more information.

November 2016: Denver Water filed our final license amendment application with the FERC. Multiple Documents and Volumes available here:

U.S. Forest Service Agreement
In September 2016, Denver Water and the U.S. Forest Service reached a Settlement Agreement to address past, current and future impacts Denver Water operations have on USFS resources. The three-part agreement identifies funding and projects to protect and preserve USFS resources, and includes:

  • Settlement Agreement – the overall master agreement describing the negotiations and resolution of issues.
  • Appendix 1 – 4(e) Conditions related to operation and maintenance of the Gross Expansion Project – these conditions will be part of the amended Federal Energy Regulatory Commission (FERC) license.
  • Appendix 2 – Off-license Agreement – commitments by Denver Water and USFS related to Denver Water’s past, existing and future operations on USFS lands.
U.S. Army Corps of Engineers 404 Permit and Record of Decision

In July 2017 the U.S. Army Corps of Engineers approved the Gross Reservoir Expansion Project by granting Denver Water its’ 404 permit and Record of Decision. The 404 permit and Record of Decision can be found below.

Clean Water Act, Section 401 Water Quality Certification

June 2016: The Colorado Department of Public Health and Environment issued the Section 401 Water Quality Certification for the Gross Reservoir Expansion Project that certifies – with the approved mitigation and enhancement measures – the project will create a “Net Environmental Benefit” on both the West and East slopes. This certification includes the following documents:

Endangered Species Act, Section 7 Consultation

December 2013: U.S. Fish and Wildlife issued its Biological Opinion on impacts of depletions of Denver Water’s entire system (not just the Gross Reservoir Expansion Project).

National Historic Preservation Act, Section 106 Consultation
October 2015: Denver Water and the State Historic Preservation Officer reached a Programmatic Agreement following a consultation process to meet obligations set forth in the National Historic Preservation Act. Following what is known as a Section 106 Consultation, this agreement fosters cooperation between Denver Water, and state and federal agencies to identify and document historic features and sets a procedural framework to follow in the event historic features are discovered.
2015 Availability Sessions

Handouts:

Posters:

Presentation:

2008 Public Meetings
Construction Traffic Documents

Documents:

 

During construction, the volume of construction traffic will vary day-to-day and month-to-month, depending on the type and number of construction activities taking place.

There may be delays caused by slow-moving construction vehicles on Gross Dam Road and Colorado 72. Other roads, such as Colorado 93, Colorado 128, U.S. 287, Arapahoe Road (U.S. 287 bypass to County Line Road) and County Line Road may be affected depending on the location of the construction materials needed to be transported to the site.

Denver Water is looking into alternatives for reducing construction traffic delays, including constructing and/or improving turnouts on Colorado 72 for slow-moving traffic.

To assure we fully understand the potential impacts, on Aug. 8, 2013, Denver Water conducted a test by using loaded trucks to gauge noise and safety issues using third-party experts who have conducted many similar studies. Learn more by viewing the videos at the following links:

Introduction

Study Overview

Passing Slow-Moving Vehicles

Intersection of Highway 72 and Gross Dam Road

Truck Noise

Dust

Conclusion

Draft FERC Hydropower License Amendment Application
  • Denver Water operates a hydroelectric power plant at Gross Reservoir under a Federal Energy Regulatory Commission (FERC) hydropower license. To expand the reservoir, Denver Water needs to amend its existing hydropower license. Denver Water is required to provide information on the proposed changes at Gross Reservoir to stakeholders (e.g., relocation of recreation facilities, changes in hydropower generation, etc.), before submitting a final application to the FERC.

Please note that the draft application is a large document and it may take a long time to download.

Draft FERC Hydropower License Amendment Application (29.34 MB)

Copies of the draft FERC hydropower license amendment application are also available for public review at:

    Environmental Impact Statement

    Click here to visit the Moffat EIS Page on the U.S. Army Corps of Engineers’ Website.

    FERC Amendment - Initial Consultation Document
    Letters to Gross Reservoir Neighbors
    Letters to Stakeholders

    Former Gov. Endorses Gross Reservoir Expansion Project

    Latest News / Blog

    Survey activity on Gross Dam Road

    Over the next two weeks, Denver Water’s contractors, Metcalf Archeological Consultants, will be conducting cultural resource surveys along Gross Dam Road. Surveys are scheduled to start the week of April 25.   Residents can expect to see crews walking along the...

    Heavy equipment to travel to Gross Reservoir Expansion Project site

    March 28, 2022 - Between March 28 and April 2, weather permitting, Kiewit Barnard Joint Venture will mobilize large equipment to the Gross Reservoir Expansion Project site. This activity will consist of a maximum of four caravans over the course of two nights. Each...

    First steps on Gross Reservoir expansion

    Feb. 27, 2022 - TAP - After 20 years of preparation, first signs of construction work emerging in vicinity of dam. After nearly two decades of planning and permitting, Denver Water’s work to expand Gross Reservoir northwest of Denver is set to kick off. Over the...

    Learning By Doing 2022 Annual Report

    Grand County Learning By Doing Cooperative Effort (LBD) has a goal to maintain, and where reasonably possible, restore or enhance the aquatic environment in the Fraser, Williams Fork, and Colorado River basins and their tributaries in Grand County, Colorado. See a...