The U.S. Bureau of Reclamation announced on Friday it will perform a Safety of Dams drilling program at Prosser Creek Dam, located just above Prosser Creek’s confluence with the Truckee River in Truckee, Calif., to evaluate the ability of the dam to resist large earthquakes.
The cost of the program is not immediately available.
Prosser Creek Dam is an earthen structure 163 feet high and 1,830 feet long, built in 1962. It is capable of storing 29,800 acre-feet of water for flood control, recreation and improvement of fishery flows in the Truckee River. Storage began in January 1963, and the water storage structure is part of Reclamation’s Washoe Project, which also includes Marble Bluff Dam and the 3.65-MW Stampede hydroelectric facility.
In 2013, Knight Construction & Supply Inc. won a contract worth US$2.1 million from Reclamation to refurbish gates at Prosser Creek Dam and in 2016 Reclamation awarded a $21.8 million contract to NW Constructors Inc. for dam safety modifications at the Stampede hydroelectric plant.
Prosser Creek Dam is located in a seismically active area, according to Reclamation.
The agency said the drilling program will help analyze the potential loss of strength, known as liquefaction that could result in a dam failure during an extreme earthquake.
Reclamation said it will continue drilling at Prosser Creek Dam throughout the summer of 2017 to collect additional data which will be used to assess the likelihood of liquefaction and response of the dam.