Blue Mesa Dam


Blue Mesa Dam is on the Gunnison river about 30 miles below Gunnison, and 1.5 miles below Sapinero, Colorado. The zoned earthfill embankment has a structural height of 390 feet, a crest length of 785 feet, and a volume of 3,080,000 cubic yards of materials.

The spillway consists of a concrete intake structure with two 25- by 33.5-foot radial gates, concrete-lined tunnel, concrete flip bucket structure, and stilling basin. Maximum discharge of the spillway is 34,000 cubic feet per second.

The outlet works consists of an intake structure, tunnel, and manifold anchor block. The outlet works is controlled by one 16- by 18-foot fixed-wheel gate in the intake structure and by two 84-inch ring-follower gates and two 84-inch hollow-jet valves in a gate house at the terminus of the outlet conduits. Maximum discharge from the outlet works is 5,000 cubic feet per second at maximum water surface elevation, with two 84-inch hollow-jet valves 62 percent open.

Blue Mesa Reservoir has a total capacity of 940,700 acre-feet and an active capacity of 748,430 acre-feet. At maximum water surface elevation, the reservoir occupies 9,180 acres.

The Blue Mesa Powerplant consists of two 30,000-kilowatt generators, driven by two 41.55-horsepower turbines. Each Turbine is designed to operate at a maximum head of about 360 feet.

One 16-foot-diameter penstock conveys water to the two turbines and also carries water for the outlet works. After branching from the main penstock, each of the penstock laterals is controlled by 156-inch butterfly valves. The main penstock is reduced by a wye branch to the outlet works control valves.


The area has undergone a rather complex geologic development. The stmtigraphic column consists of basement, pre-Cambrian granite, gneiss, and schist, overlain uncomfortably by the Jurassic, Entrada sandstone, and shale, In turn progressively overlain by the Morrison Mancos clay shales. Structurally, the sedimentary strata, underlying the volcanics and overlaying the granites, dip to the north, with the horizontal overlaying volcanics covering their erosional truncated edges. The contact between the granite and sedimentary rocks becomes progressively lower in elevation to the north of the river. On the south side of the river, it rises to the ground surface. A large normal fault parallels the canyon on the southwest side, cutting close to the river at Cimarron, below Blue Mesa Dam.

RegionFacilities in Upper Colorado | Upper Colorado Home Page
ProjectColorado River Storage
Dam Type
ReservoirBlue Mesa
Net Generation203,411,938 kWh
Original Construction1962-1966
Modified Construction
National ID NumberCO01675
Hydrologic Unit Code

Structural Height502.0 ft
Hydraulic Height (Normal Operating Depth at Dam)33.4 ft
Top Parapet (Elevation)
Spillway Crest Elevation7487.9 ft
Crest Elevation7528.0 ft
Crest Length785.0 ft
Crest Width
Base Width
Volume of Dam Construction Materials3,080,000 cu. yards
Streambed at Dam Axis7186.0 ft
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)7519.4 ft
Top of Active Conservation Pool (Elevation)7519.4 ft
Top of Inactive Conservation Pool (Elevation)7393.0 ft
Top of Dead Storage Pool (Elevation)7358.0 ft

Hydraulics & Hydrology
Total Water Storage at Elevation
Maximum Water Surface Elevation7519.4 ft
Normal Water Surface Elevation
Spillway Type
Auxiliary SpillwayNo
Spillway Capacity at Elevation34000 cfs at 7519.4 ft
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation5000 cfs at 7519.4 ft
Diversion Capacity at Elevation
Drainage Area3470.0 sq mi
Hydrometeorological Report (HMR)HMR 49
Probable Maximum Flood (PMF) Report

Contact Information
Title Western Colorado Area Office - Grand Junction
Organization Western Colorado Area Office
Address 445 W. Gunnison Ave., Suite 221 
City Grand Junction, CO 81501
Phone (Office) 970 248-0600
Organization Western Colorado Area Office - Grand Junction
Address 445 W. Gunnison Ave., Suite 221 
City Grand Junction, CO 81501
Phone (Office) 970 248-0600

Last updated: Feb 19, 2009