Sly Park Dam is located near Pollock Pines, California in the United States. The dam impounds Sly Park Creek, a tributary of the Middle Fork Cosumnes River, to form a 41000acre.foot, 650acre reservoir called Jenkinson Lake. It was constructed as part of the American River Division of the Central Valley Project to provide irrigation water to a portion of El Dorado County, California. The dam was begun on May 1953, with clearing operations, and was completed in mid 1955.The earthfill Sly Park Dam is 190ft high, with a hydraulic height of 170ft, and 760ft long. Its auxiliary dam is 130ft high and 600ft long. The spillway of Sly Park Dam is actually in the auxiliary dam: it is a concrete chute 170ft long and can carry 6700ft3 per second, while the outlet works at the foot of the dam can carry 47ft3 per second. The drainage area of Sly Park Creek behind the dam is 47sqmi. The Camino Conduit diverts water roughly 7.2mi west from the Jenkinson Reservoir for irrigation purposes. Water is also diverted from Camp Creek into Jenkinson Lake to increase the total water yield.Jenkinson Lake WatershedThe Jenkinson Lake watershed consists of the approximately 16.5 square mile area between Sly Park Dam and the Cold Canyon Tributary of Sly Park Creek. This area includes both forks of Sly Park Creek, Hazel Creek, and the Cold Canyon Tributary of Sly Park Creek. Jenkinson Lake receives insufficient inflow from this area and additional water is diverted from outside the watershed through the Camp Creek Diversion Tunnel to meet demand. The area played a significant role in the gold rush era of California's history.
