Island Lake, also known as Reservoir #15, is a privately owned reservoir located in Cedaredge, Delta County, Colorado. Built in 1954, this irrigation reservoir serves multiple purposes including irrigation and recreation, with a primary dam type of Earth construction. With a dam height of 18 feet and a storage capacity of 2355 acre-feet, Island Lake covers a surface area of 161 acres and has a drainage area of 2 square miles.

The reservoir has a significant hazard potential and is classified as fair in condition assessment, with the last inspection conducted in June 2020. It has uncontrolled spillways, slide and sluice gate outlet gates, and a maximum discharge capacity of 600 cubic feet per second. Despite its moderate risk assessment rating, the reservoir remains a vital water resource in the area, supporting agricultural activities and providing recreational opportunities for local residents and visitors alike.

Managed by the Colorado Division of Water Resources, Island Lake plays a crucial role in water management and conservation efforts in the region. With its picturesque location and essential functions, this reservoir serves as a valuable asset for water resource and climate enthusiasts interested in the sustainability and resilience of water systems in Colorado.