Gross Reservoir Expansion Project
Providing a Net Environmental Benefit for Colorado
Denver Water has committed to more than 60 different mitigation and enhancement projects on both the West and East Slopes with a total cost of more than $20 million. Denver Water will be collaborating with numerous stakeholders to preserve the aquatic environment on a cooperative basis. Some of the projects include:
Greenback Cutthroat Trout Recovery
South Boulder Creek Habitat Restoration
Denver Water will restore approximately two miles of South Boulder Creek with the City of Boulder
Williams Fork Restoration
Denver Water will restore approximately two miles of the Williams Fork River in Grand County.
Fraser Sediment Ponds
Denver Water has partnered with Colorado Department of Transportation, Grand County, and the town of Winter Park to capture traction sand used on Hwy. 40 to improve water quality and trout habitat in the Fraser River.
Environmental Pool
Denver Water will establish a 5,000 acre-foot environmental pool in Gross Reservoir that will be used to increase streamflow during low flow periods. This will benefit 17 miles of aquatic habitat in South Boulder Creek from Gross Dam to its confluence with Boulder Creek.
Learning by Doing
Denver Water is a partner in Grand County’s groundbreaking “Learning By Doing” program –
pursuing the goal to “maintain, and, where reasonably possible, restore and enhance the conditions of the aquatic environment in Grand County.”
Long Term Water Quality Monitoring
Denver Water will monitor stream temperatures,
water quality, aquatic insects and channel stability in numerous streams on both West and East slopes.
Stream Restoration on the North Fork South Platte River
Denver Water is committed to preserving and enhancing the environment and habitats that make up our watersheds. We’re proud that in issuing the Gross Reservoir Expansion Project’s 401 Water Quality Permit, the Colorado Department of Public Health and Environment noted the project will have a “net environmental benefit” on the state’s water quality.
Colorado Rivers and Streams
Through the Colorado River Cooperative Agreement, the Gross Reservoir Expansion Project will provide the following benefits:
In partnership with the Cities of Boulder and Lafayette, establishes a 5,000 acre-foot environmental pool, which will enhance stream flow in South Boulder Creek during low flow periods, benefiting 17 miles of aquatic habitat.
Funds multiple water improvement and stream restoration efforts in collaboration with county officials, Trout Unlimited and other interested parties. The Williams Fork River restoration project is one example of these improvements being completed by Denver Water and in partnership with Colorado Parks & Wildlife.
- $50,000 committed to stream channelization improvements on the Fraser River.
- Collaborative effort between Denver Water, Colorado Department of Transportation, Grand County and the U.S. Forest Service to modify Denver Water’s diversion structure on the Fraser River to allow the removal of road sand, which has improved stream quality on the Fraser River.
Protecting Our Resources
A leader in the Colorado River Endangered Fish Recovery Program, a strong coalition of states, agencies and environmental groups cooperating in the restoration of habitat for the humpback chub, Colorado pike minnow and other fish species.
Latest News / Blog
Gross Reservoir recreation opening Saturday, July 2
Boulder, Colo. — July 1, 2022 — Recreation at Gross Reservoir will reopen Saturday, July 2, after a two-week closure to recover a vehicle from the reservoir following a fatal accident at the construction site for the dam expansion project on June 18. Operations for...
Long-term recreation closure at Gross Reservoir
Boulder, Colo. — June 22, 2022 — Recreation at Gross Reservoir will remain closed for multiple weeks following the June 18 fatal accident at the Gross Reservoir Expansion Project where an engineer with six years of experience lost his life. This is essential as crews...