Chimney Hollow Reservoir Project

Chimney Hollow Reservoir Project 

A New and Much-Needed Reservoir  

The Chimney Hollow Reservoir Project is a collaborative effort by 12 Northeastern Colorado water providers to improve the reliability of the Windy Gap Project. Chimney Hollow Reservoir will be located just west of Carter Lake in Larimer County. Its 90,000 acre-feet of dedicated storage capacity will supply a reliable 30,000 acre-feet of water each year for future generations. Construction began in August 2021.   

This project will not take water away from irrigated agriculture or other users, but will utilize the water rights currently associated with the existing Windy Gap Project, which has been delivering water since 1985. Once built, Chimney Hollow Reservoir will provide the additional storage needed to improve the Windy Gap Project’s reliability for its participants and constituents. 

The Windy Gap Firming Project (of which Chimney Hollow Reservoir is the major component), was reviewed and approved under the National Environmental Policy Act. NEPA, state and local approvals and requirements, plus substantial negotiations, will result in robust mitigation, enhancements and protection for fish, wildlife and the environment, to address the project's impacts. 

Chimney Hollow Reservoir Project Website