Protecting Colorado River Flows by Preventing Dam Expansion

Guardians is part of a coalition that is seeking to halt Denver Water’s proposed expansion of Gross Dam in Boulder County, Colorado, and to protect flows in the Colorado River. Federal agencies charged with permitting the project failed to comply with environmental laws including the Clean Water Act, and failed to ensure the health of the Colorado River, its native and imperiled species, and communities across Colorado that will be negatively impacted by the project. This litigation comes at a time when the basin states are working to put together a Drought Contingency Plan to address falling levels in Lake Mead and Lake Powell due to extensive drought and climate change. Scientists predict that climate change will further drain the river in the coming decades, thus further imperiling water supplies and river health in the future. The Moffat Project is just one of a series of proposed water projects that look to develop the last bit of water left to sustain the already compromised Colorado River.

Denver Water’s Moffat Collection System Project involves diversion of additional water from the headwaters of the Colorado River, transport in the existing Moffat Tunnel through the Continental Divide, and release into South Boulder Creek for storage in the proposed expansion of Gross Dam and Reservoir. The project will triple the storage capacity of Gross Reservoir and the dam will become the tallest dam in the history of Colorado. Denver Water moved to dismiss the case for lack of jurisdiction once the City received a permit from the Federal Energy Regulatory Commission (FERC) on the theory that a decision involving a FERC license can only be challenged in the Court of Appeals. The court granted the motion to dismiss for lack of jurisdiction. The case was appealed to the Tenth Circuit Court of Appeals where the Court held oral argument on May 18, 2022. Awaiting a decision.