Twin Lakes Dam and Reservoir is located approximately 13 miles south of Leadville, in Lake County.  The reservoir has a total capacity of 141,000 acre-feet. The dam is a zoned, rolled earthfill structure with a height above streambed of 53 feet. The crest of the dam is 30 feet wide and 3,150 feet long.

The spillway is on the left abutment of the dam, and has a capacity of 1,400 cfs. The spillway is an uncontrolled concrete morning-glory inlet structure with a 9-foot-diameter concrete conduit under the dam embankment and a concrete stilling basin. A channel downstream from the stilling basin caries the water to Lake Creek.  The outlet works located in the right abutment delivers 3,465 cfs to the river.  

The outlet works has an inlet structure with a trash rack, a 12-foot-diameter concrete conduit with a steel liner, and a gate chamber housing a 9-by-12-foot high pressure gate. A 16.75-foot-diameter horseshoe-shaped concrete conduit containing a 12.0-foot-diameter steel outlet pipe leads from the gate chamber to the river outlet control house where two 6.5-by-8.0-foot high-pressure gates are located.  A chute, stilling basin, and a 400-foot-long outlet channel lead to Lake Creek.