Plan to expand Colorado mountain reservoir could double water storage near Alma

A plan is moving forward to expand Montgomery Reservoir in Colorado's mountains, potentially doubling its capacity as water providers look to shore up supplies in the increasingly dry West. Officials with Colorado Springs Utilities say the project is part of a broader effort to modernize aging infrastructure and better capture water that is currently going unused.  

"It is nearly 70 years old," Water Resource Planner Maria Pastore said. "So, it will also help meet our water management needs by addressing current storage capacity constraints that we have."

The reservoir, built in 1957, is part of the Continental-Hoosier System, a transmountain network that moves water from the Blue River basin to Colorado Springs. That system supplies about 13% of the city's drinking water and is entirely gravity-fed, making it one of the most efficient pieces of infrastructure in the region, according to Colorado Springs Utilities.

But right now, Colorado Springs Utilities says it's missing opportunities to store water during good years.

"We're not able to divert physically and legal water supplies that we could capture if we had a bigger bucket," Pastore said.

The proposal would expand the reservoir from about 5,700 acre-feet to roughly 13,800 acre-feet, more than doubling its storage capacity.

That could allow an additional 4,000 acre-feet of water to be captured annually from existing water rights.

Across the West, water managers are increasingly focused on storage as snowpack becomes less reliable.

"Storage is just critical for our systems," Pastore said. "Especially with high elevation storage, we have less evaporation."

The project is also tied to long-term planning for population growth and drought resilience. Colorado Springs Utilities says expanding existing infrastructure now is more efficient than building entirely new systems later.

The Continental-Hoosier System itself dates back to 1957 and was originally designed with future expansion in mind, meaning this proposal has been decades in the making. Still, the expansion would increase the footprint of the reservoir and raise the height of the dam, something officials acknowledge could impact a popular recreation area near the mountain town of Alma.

"We understand that to be very important to the community up there," Pastore said. "Those public benefits, the hiking, the fishing, off-road access, those will all remain the same once construction is complete."

The project is currently in the permitting phase, with applications for local, state, and federal approval expected this year. If approved, construction could begin as early as 2028 and continue into the early 2030s.

Utilities say they plan to stay in regular contact with the community through updates as the project moves forward, and have already done one community meeting with the surrounding neighborhood.