| Fontenelle Dam | |
|---|---|
 | |
| Location | Lincoln and Sweetwater counties, Wyoming, USA |
| Coordinates | 42°01′42.4″N 110°03′37.9″W / 42.028444°N 110.060528°W |
| Construction began | 1961 |
| Opening date | 1964 |
| Operator(s) | U.S. Bureau of Reclamation |
| Dam and spillways | |
| Type of dam | Zoned earthfill |
| Impounds | Green River |
| Height | 139 feet (42 m) |
| Length | 5,421 feet (1,652 m) |
| Dam volume | 5,265,000 cu yd (4,025,000 m3) |
| Spillway type | Gated spillway |
| Spillway capacity | 20,200 cu ft/s (570 m3/s) |
| Reservoir | |
| Creates | Fontenelle Reservoir |
| Total capacity | 345,360 acre-feet (426.00 GL) |
| Catchment area | 4,156 sq mi (10,760 km2) |
| Power Station | |
| Hydraulic head | 121 ft (37 m) |
| Turbines | 1 x 10 MW Francis-type |
| Installed capacity | 10 MW |
Fontenelle Dam was built between 1961 and 1964 on the Green River in southwestern Wyoming. The 139-foot (42 m) high zoned earthfill dam impounds the 345,360-acre-foot (0.42600 km3) Fontenelle Reservoir. The dam and reservoir are the central features of the Seedskadee Project of the U.S. Bureau of Reclamation, which manages the Fontenelle impoundment primarily as a storage reservoir for the Colorado River Storage Project. The dam suffered a significant failure in 1965, when the dam's right abutment developed a leak. Emergency releases from the dam flooded downstream properties, but repairs to the dam were successful. However, in 1983 the dam was rated "poor" under Safety Evaluation of Existing Dams (SEED) criteria, due to continuing seepage, leading to an emergency drawdown. A concrete diaphragm wall was built through the core of the dam to stop leakage.