| Pit 5 Dam | |
| Location Map: | California |
| Location Map Caption: | Location of Pit 5 Dam in California |
| Coordinates: | 40.9917°N -121.8711°W[1] |
| Country: | United States |
| Location: | Shasta County, California |
| Purpose: | Hydroelectric |
| Opening: | 1944 |
| Owner: | PG&E |
| Dam Crosses: | Pit River |
| Dam Height Foundation: | 58feet[2] |
| Dam Length: | 340feet |
| Res Name: | Pit 5 Reservoir |
| Res Capacity Total: | 330acre feet |
| Plant Name: | Pit 5 Powerhouse |
| Plant Capacity: | 160 MW |
| Plant Annual Gen: | 781,328,000 KWh (2001–2012)[3] |
Pit 5 Dam is a run-of-the-river hydroelectric dam on the Pit River in Shasta County, northeastern California, about 2miles south of Big Bend. It is part of the Pit 3-4-5 hydroelectric project owned by Pacific Gas & Electric Company.[4]
The concrete gravity diversion dam is 58feet high and 340feet long.[2] It has a gated spillway controlled by four 50x steel wheel gates, and a 30inches diameter river outlet for regular releases. An intake structure diverts water into a 5109feet long penstock to the Pit 5 Tunnel forebay reservoir, from which a second 23149feet tunnel connects to the Pit 5 power station. There are four 40 MW generating units, each fed by a 1380feet-long penstock.[5]
The dam and power station were authorized in 1942 and constructed as a wartime project, and the first power was generated on April 29, 1944.[6] Construction of the dam and power station dewatered a stretch of the Pit River known as the "Big Bend". When the projects were relicensed in 2007, a minimum 250cuft/s release[5] into the river was established, to provide recreation benefits such as boating and fishing, and to improve riparian habitat.[7]