Construction Begins at Chimney Hollow Reservoir

On Aug. 16, 2021, Northern Water’s Municipal Subdistrict issued a Notice to Proceed to Barnard Construction Co. Inc. to begin construction of Chimney Hollow Reservoir. Environmental and mitigation efforts have also begun in the Upper Colorado River basin. 

Chimney Hollow Reservoir, the key component to the Windy Gap Firming Project, will bring a reliable water supply to the 12 municipalities, water providers and utilities paying for its construction, as well as provide a much-needed recreation area to be managed by the Larimer County Department of Natural Resources. Chimney Hollow Reservoir will be located in a dry valley just west of Carter Lake in southwest Larimer County and will store 90,000 acre-feet of water from the Windy Gap Project for use by 12 participants, including Broomfield, Platte River Power Authority, Longmont, Loveland, Greeley, Erie, Little Thompson Water District, Superior, Louisville, Fort Lupton, Lafayette and Central Weld County Water District. Chimney Hollow Reservoir will make the Windy Gap water supply serving those participants more reliable and meet a portion of their long-term water supply needs. 

During the groundbreaking ceremony on Aug. 6, Heather Banks, Chair of the Windy Gap Participants Committee said, “This day is the realization of over 20 years of hard work, planning and partnerships along the Front Range as well as on the West Slope.”  

Construction is anticipated to take four years and water will begin to be stored in the reservoir in 2025.