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About the Project

What is the Gross Reservoir Expansion Project? Environmental Benefits

The Gross Reservoir Expansion Project is one of the major elements of Denver Water’s long-term supply plan. It will prevent future shortfalls during droughts and correct a serious imbalance in our north-south collection systems.  

With this project, Denver Water will provide future water security to our customers — one-quarter of the state’s population — by increasing redundancy and flexibility in our system to guard against the impacts of climate change. At the same time, the project will provide a net environmental benefit to the state’s water quality and address the environmental impacts through mitigation and enhancement projects on both sides of the Continental Divide. 

When the reservoir begins to fill to its new, increased capacity in 2027, the project will have spanned nearly a quarter-century from the start of environmental study and permitting to the end of construction.  

In December 2021, the Denver Board of Water Commissioners approved a $531 million construction contract for the expansion of Gross Reservoir. The road to get to this value started through a bidding process, which brought Kiewit-Barnard Joint Venture into the project team early to identify efficiencies in design and construction to reduce the final construction cost.  

The project is an investment on many levels. First, it is an investment in a secure water future for Denver Water customers who live and work on Colorado’s Front Range. It’s also an investment in the local and regional economy, creating jobs and opportunities in industries beyond engineering and construction.