Strontia Springs Reservoir is a 98-acre man-made lake located in Waterton Canyon south of Littleton, Colorado. Created in 1983 by the 243-foot Strontia Springs Dam, the reservoir serves as a crucial water source for Denver, with approximately 80% of the city's water passing through it.

IMPORTANT: Boating and paddling are strictly prohibited on Strontia Springs Reservoir and the South Platte River through Waterton Canyon. This restriction is enforced by Denver Water to protect the drinking water supply.

The reservoir sits at an elevation of 6,002 feet and has a capacity of 7,864 acre-feet. While paddling is not permitted, the surrounding area offers significant natural attractions. The reservoir and canyon are home to Rocky Mountain bighorn sheep, mule deer, black bears, mountain lions, elk, and over 40 species of birds including herons, warblers, flycatchers, owls, and buntings.

Access to the reservoir requires a 6.5-mile journey along the Waterton Trail, which is open to hiking, biking, and horseback riding. The Bighorn Sheep Rest Area near the reservoir provides bathrooms and picnic facilities. The reservoir connects to multiple trail systems including the Colorado Trail and routes into Roxborough State Park.

The South Platte River, which feeds the reservoir, flows clean and clear but is not potable without treatment. The steep shorelines around the reservoir make water access challenging. Before the dam's construction in 1983, this section of Waterton Canyon was known for challenging whitewater, including the infamous "Widowmaker" stretch which now lies submerged beneath the reservoir.

The area is open year-round from 30 minutes before sunrise to 30 minutes after sunset. No dogs or other pets are allowed in the canyon to protect the wildlife populations.