Stony Gorge Dam, Safety of Dams Project
Stony Gorge Dam is located about 18 miles downstream from East Park Dam on Stony Creek and about 25 miles west of the town of Willows. Studies ongoing since 2001 indicated that a large earthquake could cause the vertical concrete buttresses that support the dam to buckle, possibly leading to subsequent dam leakage or collapse.
Construction of the structural modifications began in January 2007 and were completed in January 2009. The dam modifications consisted of building a concrete wall and additional supports between the vertical buttresses to provide increased stability to them during a possible earthquake.
Stony Gorge Dam has a structural height of 139 feet and a crest length of 868 feet. The reservoir, which has a storage capacity of about 50,000 acre-feet, regulates flows along the lower reaches of Stony Creek, stores surplus water for irrigation purposes, and provides for hydropower and recreation. Releases from the reservoir travel 22 miles down Stony Creek to Black Butte Dam and Lake.
The dam is part of the Orland Project, one of the oldest projects in Reclamation. Construction was completed in 1928. Principal crops made possible by irrigation water from the reservoir are alfalfa, hay, sorghum, olives, almonds, walnuts, and citrus fruit.