Upper Black Creek Reservoir, also known as Blue Lake, is a private water resource located in Summit County, Colorado. Constructed in 1957, this reservoir serves multiple purposes, including irrigation and recreation for the local community. With a dam height of 41 feet and a maximum storage capacity of 672 acre-feet, the reservoir covers an area of 21 acres and has a drainage area of 16 square miles.

Despite its importance for water supply and recreational activities, Upper Black Creek Reservoir poses a significant hazard potential and has been assessed as unsatisfactory in condition. The dam features an uncontrolled spillway and a single slide gate for outlet control. The reservoir is regulated by the Colorado Division of Water Resources and undergoes regular inspections, with the last assessment conducted in June 2020. Although the risk assessment indicates a moderate level of risk, there is a need for ongoing risk management measures to ensure the safety and integrity of the dam structure.

In the event of an emergency, the reservoir is equipped with emergency action plans, although the last revision was in 2011. With its location in a picturesque setting near Black Creek and Kremmling, Upper Black Creek Reservoir remains a valuable water resource for the region, while also highlighting the importance of proper maintenance and monitoring to mitigate potential risks associated with dam infrastructure.