Sunset Lake, located in Longmont, Colorado, is a local government-owned reservoir primarily used for irrigation purposes. Managed by the Gravel Mining Company, this Earth-type dam sits on the St. Vrain River, with a structural height of 15 feet and a storage capacity of 260 acre-feet. The dam also serves as a fish and wildlife habitat, as well as a recreation area for enthusiasts in the community.

With a low hazard potential and a moderate risk assessment rating, the Sunset Lake dam is regulated by the Colorado Department of Water Resources, ensuring regular inspections and enforcement measures are in place to maintain its safety. The spillway, with a width of 38 feet, is uncontrolled, allowing for controlled discharge during periods of high water flow. While the emergency action plan status and risk management measures are yet to be assessed, Sunset Lake remains a vital water resource for the surrounding area, demonstrating the importance of sustainable water management practices in the face of climate change challenges.