North St. Vrain Creek Restoration

Press Enter to show all options, press Tab go to next option

at Button Rock Preserve

North St Vrain Creek
North St Vrain Creek before phase 1
North St Vrain Creek Spillway
Water being released from Button Rock Dam


Button Rock Preserve is an approximately 3,000 acre property owned by the City of Longmont on North St. Vrain Creek about 7 miles west of Lyons. The Preserve is maintained by the City of Longmont as a protected watershed that provides the majority of the drinking water for Longmont and Lyons. The Preserve contains approximately 4 miles of North St. Vrain Creek and two reservoirs: Ralph Price Reservoir (Button Rock) and Longmont Reservoir.

The floods of September 2013 drastically altered North St. Vrain through Button Rock Preserve. The City of Longmont is working to restore the North St. Vrain to a natural and resilient river that provides clean drinking water, excellent fishing opportunities, wildlife habitat, and other valuable ecosystem services.

Restoration Projects

Button Rock Preserve Restoration Map 

View a PDF of the map showing the restoration areas >

The restoration of North St. Vrain Creek is being undertaken in two phases.

Phase 1 - Completed

The Phase 1 project encompassed in-channel and riparian plant community restoration along 1,750 feet of the creek below Longmont Dam in the entrance to Button Rock Preserve. This phase of the restoration was managed by Boulder County. Learn more about Phase 1 work on Boulder County's project web page >

Phase 2

Phase 2 of the restoration work takes place in the 1.3-mile stretch between Longmont Reservoir and the Button Rock Dam spillway in Button Rock Preserve. The City of Longmont is managing the Phase 2 project work. This project will incorporate two sub-reaches of in-channel restoration work with an extensive riparian ecosystem replanting effort.

This restoration work is included in the Forest Stewardship Plan for Button Rock Preserve.

Timeline & Status

Phase 1 - Completed

The Phase 1 restoration project has been completed. The in-channel restoration of the low flow channel and floodplain was completed in March 2016. Replanting of the riparian corridor took place in summer 2016. This restoration work was coordinated with the reconstruction of Longmont Dam Road. Learn more about the Longmont Dam Road project work >

The video above shows restoration project work creating bank structures as part of Phase 1.

Phase 2

The initial design for the Phase 2 work was completed in summer 2015. In-stream construction will take place for two priority sub-reaches in spring 2017. These two priority sub-reaches are 1) immediately upstream of Longmont Reservoir and 2) at the confluence of the Button Rock Dam Spillway with North St. Vrain Creek.

Additional in-stream restoration work will be carried out at Chimney Rock Dam to improve fish passage and other habitat. This additional work is anticipated for fall 2017.

Replanting is also planned to begin in spring 2017 and continue through fall 2017 to restore the riparian plant community that was lost during the September 2013 flood.


The restoration work on North St. Vrain Creek in Button Rock Preserve is being managed jointly by Boulder County and the City of Longmont.

Colorado Parks and Wildlife has awarded $84,000 toward the project as part of its "Fishing is Fun" program. Read a news release from CPW about the award >

The St. Vrain Anglers chapter of Trout Unlimited provided a $30,000 cash match grant for the project, which was used to help Longmont qualify for the CPW grant.


Watershed & Wildfire Resiliency Coordinator, Keith Stagg

Free viewers are required for some of the attached documents.
They can be downloaded by clicking on the icons below.

Acrobat Reader Flash Player QuickTime Windows Media Player Microsoft Silverlight Word Viewer Excel Viewer PowerPoint Viewer
View Full Site