Colorado Springs Utilities presents plan to enlarge Montgomery Reservoir; says no new water rights needed

Colorado Springs Utilities outlined plans July 14 to enlarge Montgomery Reservoir as part of the Continental/Hoosier System project, a transmountain diversion that moves water from the Upper Blue River watershed under the Continental Divide to Colorado Springs.

Maria Pastore, a water-resource planner and the project technical lead, told the Breckenridge council the reservoir enlargement would add roughly 8,100 acre-feet of storage to improve resiliency, redundancy and efficiency of the existing system. She said the enlargement was anticipated when Montgomery Reservoir was first built about 60 years ago and that the reservoir is due for lifecycle maintenance by 2030, making that timeframe logical for enlargement and upgrades.

Pastore said the project would not require new water rights and would rely on operational changes and existing conditional storage rights that were resolved under a 2020 Blue River settlement. “No new water rights are needed,” she said, and added that the project will use bypass flows and volumetric limits as part of the National Environmental Policy Act (NEPA) assessment to avoid significant impacts.

She described the CHS as Colorado Springs Utilities’ first transmountain diversion project, diverting water from the Upper Blue River watershed and transporting it via tunnels and the Hoosier Tunnel under the Continental Divide to Montgomery Reservoir. From Montgomery, water is carried about 70 miles by gravity-fed pipeline to storage in the Colorado Springs metropolitan area. The current diversion season runs April through the end of September, and Pastore said annual variability and priority calls can limit diversions in dry years.

The project is proceeding on an environmental-assessment track under NEPA, Pastore said, with planned federal, state and local permit applications, including Summit County and Park County 1041 permits. A Summit County pre-application was submitted in March 2024 and county staff determined the project requires a major review. Pastore said Colorado Springs Utilities plans to submit a Summit County 1041 application by the end of the calendar year and anticipates permitting decisions by 2028, with construction to follow.

Council members asked whether the project would affect Breckenridge’s water rights or local recreation such as boating and fishing. Pastore and Colorado Springs staff said hydrologic modeling and a streamflow analysis did not identify impacts to Breckenridge water rights and that any reductions in streamflow during above-average years would be managed within existing volumetric limits. Utilities staff pointed to the Shoshone outage protocol — which requires stopping diversions when Shoshone flows drop below a defined threshold — as an operational protection for downstream flows.

Why it matters: The project would increase storage capacity that Colorado Springs Utilities says it cannot currently capture, allowing carryover through drought periods and maintaining deliveries during pipeline outages. The enlargement will alter physical infrastructure in Park County while operational and legal aspects in the Blue River Basin are managed through agreements and NEPA disclosures. The council heard the presentation as an informational briefing and was asked to be prepared to supply data and coordination if the Summit County 1041 process requests local information.

What’s next: Colorado Springs Utilities plans a Summit County 1041 application this year and completion of NEPA/permitting steps with an expectation of decisions by 2028 and construction thereafter. The county-level application and the NEPA assessment will include opportunities for public review, and staff said bypass flows will be part of the mitigation approach.

Provenance: Topic introduced SEG 028; presentation and Q&A through SEG 152 and 255.