Gilpin County Historic Courthouse front porch/entrance will be closed May 16 to June 17. Signs will redirect visitors.


Gross Reservoir Expansion Project


Project updates

This May 2024, Denver Water and its contractor, Kiewit Barnard, will begin placing concrete to raise Gross Dam. They will build 118 concrete steps from the bottom of the existing dam to the new dam crest, 131 feet above the existing dam. Be on the lookout for a postcard to learn more about what to expect during this phase of construction.

Denver Water is also working diligently to reopen Gross Dam Road to the public. Due to the severity of the rockfall caused by the March snowstorm, and based on guidance from geotechnical engineers, they have implemented a two-phase approach to reopen the road. The first phase, completed in late March, reopened the road for emergency responders only. Now that the road is clear of debris, they will begin phase two and fully assess what additional repairs are needed to ensure the road is suitable for unrestricted public use. They will update the project MyMap once they have an estimated timeline to reopening the road and the Fisherman's Parking Lot.

If you have questions, please stop by Canyon Coffee for their in-person office hours on Wednesdays from 8 - 10 a.m. (weather permitting) or email them at

Other News

β€œIn 2023, the project team completed the abutment excavation, hydro demolition of the dam face and a full-scale roller-compacted concrete test placement. We also nearly completed the foundation grouting and erection of the crusher and batch plants. In short, the preparatory work is almost complete, and the project is on track to start the dam raise in the spring of 2024.” - Jeff Martin, Denver Water Gross Reservoir Expansion Program Manager. 2023 Year in Review.

Gross Dam ready to go up. Final preparations underway at reservoir before dam raise begins.

Safety gets top billing for Gross Dam project. Denver Water has two priorities when it comes to the construction of the Gross Reservoir Expansion Project. One: Build a dam that will last hundreds, if not thousands of years. Two: Build it as safely as possible.