Deer Creek Reservoir Dam

Provo River Water Users Association:
The Provo River Water Users Association was formed during a desperate water shortage in 1930’s. The City of Provo, Salt Lake City, and five other Utah County cities that needed additional domestic water supplies joined with local irrigation interests to sponsor the Provo River Project.

Deer Creek Reservoir Dam Description:
Deer Creek Dam is a zoned earth-fill structure located on the Provo River approximately 16 miles northeast of Provo, Utah. Deer Creek Reservoir, the impoundment created by the dam, is a major municipal and industrial water supply as well as an important irrigation supply for the Wasatch Front. Deer Creek Reservoir holds 152,564 acre-feet when full.

Why was the Deer Creek Dam Built?
The Deer Creek dam was constructed as part of the Provo River Project to store water diverted from the Provo, Weber, and Duchesne Rivers under Project and Association water rights. At the base of the dam is the Bureau of Reclamation’s Deer Creek Power Plant which is operated by the Association. Information courtesy of PRWUA

When was the Deer Creek Dam Built?
The dam was constructed from 1938-1941 as part of President Roosevelt’s National Recovery Act of 1933. Construction of all Project facilities was completed in 1951. The Deer Creek Power Plant was constructed later and was completed in 1958.

How Big is the Deer Creek Dam?
Zoned as an earth-fill structure
2.81 cubic yards of fill.
235 feet high
Crest length of 1,304 feet

Deer Creek Reservoir Statistics:
Capacity is 152,564 acre-feet
149,700 acre-feet is active pool, and the remaining
2,864 acre-feet is dead pool
The spillway is a concrete chute at the right abutment controlled by two radial gates with a capacity of 12,000 cubic feet per second (cfs).
Surface area of approximately 2,700 acres at full capacity
Used extensively for recreation, including boating, fishing, and swimming.

An evaluation of Deer Creek Dam, funded by Reclamation under the Safety Evaluation of Existing Dams program, identified potentially liquefiable soils in the original design and construction of the dam. Liquefiable soils are soils susceptible to liquefaction in a large seismic event. Extensive drilling and testing confirmed the presence of these soils.

Having identified a potential risk, Reclamation design team developed a project to reinforce the dam. The project started with dewatering the downstream toe of the dam by drilling a series of wells and then pumping to lower the groundwater level below the river level. When the groundwater was lowered to an acceptable level, excavation began to remove the liquefiable soils. These soils are then replaced with a dense, highly compacted soil carefully designed to retain its strength and structural integrity in the event of a large earthquake near the dam. This compacted soil is called the “shear key”. In addition to the reinforcement work, a modern seepage monitoring and drainage control system is being installed.

The estimated cost of the project is $15 million and is being funded under the Safety of Dams Act passed by the United States Congress in 1978. This legislation requires the local project sponsor, in this case the Provo River Water Users Association (PRWUA), to fund 15% of the cost with the Federal government picking up the rest of the cost. Since the Metropolitan Water District of Salt Lake and Sandy is the largest shareholder in the PRWUA, tax and ratepayers in Salt Lake City & Sandy City are paying about $1 million towards the project costs.

John Robert Carman, General Manager, Metropolitan Water District of Salt Lake and Sandy