Gross Reservoir
Expansion Project
Gross Reservoir
Expansion Project
For information on blasting schedules, public access and roadwork activities, click the My Map image below.
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Environmental Commitments

Online Office Hours
Now that construction has begun, we will continue to offer online one-on-one appointments with our project representatives who can answer your questions about the Gross Reservoir Expansion Project. We invite you to search for an available time and book an online meeting here.
We look forward to speaking with you!
News
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...
Gross expansion is a go after federal, state and local reviews finalized
TAP - November 8, 2021 - Project to raise dam will improve water reliability for more than 1.5 million people while benefiting the environment. After nearly 20 years of preparations, the expansion of Gross Reservoir in Boulder County is moving ahead. Last week, Denver...
News
Denver Water, Boulder County strike agreement to address construction impacts, improve road safety, and enhance environment, open space and recreation as part of reservoir project
Denver — Wednesday, Nov. 3, 2021 — Denver Water and Boulder County have entered into an agreement related to the Gross Reservoir expansion that marks the final step in a nearly 20-year federal, state and local review to permit the project. Denver Water will commit...
Breathtaking work nearly 300 feet underwater
August 23, 2021 - TAP - Major project replacing large debris grate at Gross Dam requires experts in the harrowing field of saturation diving. Raitt stresses the project is wholly unrelated to the planned expansion of Gross Reservoir. It would be happening regardless...
All the ways we save (It’s not just shorter showers!)
August 6, 2021 - TAP There are a few things many customers might know about Denver Water’s efforts to use water efficiently. There was that fun and flashy and very effective 10-year “Use Only What You Need” campaign that cut per person water use by 22%. Denver Water...
Could Colorado cities save enough water to stop building dams?
Aug. 6, 2021 - Colorado Sun - Conservation groups want more “cash for grass” and other plans to acquire new water by saving it. But Denver and Aurora, among others, say there’s only so much to cut before a new dam is needed. Denver Water, serving 1.5 million customers...