Colorado River Connectivity Channel
A New Channel for Fish and Sediment Passage
As part of the Windy Gap Firming Project’s permitting phase to build Chimney Hollow Reservoir, the historical impacts of the original Windy Gap Project were also evaluated, including the loss of river connectivity following construction of the Windy Gap Reservoir dam on the Colorado River.
To minimize the dam’s impact on aquatic habitat and species, the Municipal Subdistrict, which owns and operates the Windy Gap Project, agreed to decrease the reservoir’s footprint and construct a connecting channel around the reservoir capable of passing water, fish and sediment, thereby reconnecting two segments of the Colorado River.
Construction activities began summer of 2022 and were completed in fall 2024. A ribbon cutting ceremony took place on Oct. 15, 2024 with many of the project partners taking part in the event.
The Colorado River Connectivity Channel project, which will also allow public access for fishing along most of the new channel, includes:
- Windy Gap Dam Embankment Modification - A new southern embankment will create a smaller reservoir and provide space to construct the new channel and floodplain.
- Diversion Structure - A new diversion structure will direct and allocate river flows between the reservoir and the new connectivity channel. The structure will allow sufficient flow into the reconfigured reservoir to meet pumping requirements when the Windy Gap Project’s water rights are in priority, while also maintaining flow in the connectivity channel for sediment and fish passage.
- Connectivity Channel - A new channel and floodplain will connect the Colorado River above and below the reconfigured reservoir. To the extent possible, the new channel and floodplain will allow natural geomorphic and ecological river processes to take place while maintaining dam safety.
- Fraser Stream Gauge Retrofit - Improvements to the Fraser River stream gauge immediately upstream of Windy Gap Reservoir will facilitate fish passage.
Project Partnerships
Multiple invested stakeholders are assisting to ensure a successful connectivity channel project. Stakeholder contributions include design, project management, fund raising and time. The Municipal Subdistrict and Trout Unlimited contracted with AECOM to conduct the final design. Other project partners include Colorado Parks and Wildlife, Colorado Water Conservation Board, Grand County, the Colorado River District and the Upper Colorado River Alliance.