Gross Reservoir Expansion Project

As a federally permitted project, the purpose, need and environmental impacts of the project have been vetted through almost a decade of research. The U.S. Army Corps of Engineers released the Final Environmental Impact Statement (FEIS) in 2014 that details project mitigation measures and addresses public comment received after publication of the Draft Environmental Impact Statement. Like many water supply projects, there are a number of permits at the federal, state and local level that are needed before construction can begin:

401 Certification

  • Also a component of the Clean Water Act of 1972, 401 Certification is a process handled at the state level. In the case of the Gross Reservoir Expansion Project, the Colorado Department of Public Health and Environment (CDPHE) is responsible for evaluating the impacts of and ensuring water quality associated with this project.
  • Secured: June 2016

Record of Decision (ROD) and 404 Permit

  • A major responsibility of the Army Corps of Engineers (ACE) is administering the permitting program under Section 404 of the Federal Water Pollution Control Act of 1972, also known as the Clean Water Act. Permit review and authorization is a thoughtful and lengthy process that encourages avoidance of impacts, followed by minimizing impacts and, finally, requiring mitigation for unavoidable impacts to the aquatic environment.
  • 404 Permit
  • Secured: July 2017.

Federal Energy Regulatory Commission (FERC) License Amendment

  • The Gross Reservoir Dam includes a 7.6 mW hydropower unit, which is licensed for operation by FERC. Under the Federal Power Act, FERC has exclusive authority to license nonfederal hydropower projects. The amendment of license process requires that FERC address both the economics and engineering issues and the potential environmental and socioeconomic effects of project development and operation.
  • Denver Water expects to receive the License Amendment by the end of 2018.

Latest News / Blog

New technologies under review

The trees removed from the expanded reservoir may have a new life as “biochar,” improving soil for plants. Denver Water TAP - Expanding a reservoir has a lot of challenges, among them dealing with the trees and bushes that must be removed. Leaving this biomass in...

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Successful 2018 yurt season

With the sun drifting ever lower in the sky and the brilliant colors of fall a pleasant memory, the 2018 season for the Gross Reservoir Expansion’s Public Information Yurt has come to a successful finish. It was a great year marked by constructive two-way...

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