Geologists with the U.S. Department of Interior’s Bureau of Reclamation have begun extracting core samples from on, around and deep within Shasta Dam in California, in preparation for a proposed dam raise.
Reclamation proposes to raise the height of the dam by 18.5 feet but first needs to characterize the concrete and geology conditions. The agency has been studying the idea of raising the dam and enlarging the reservoir since the 1980s.
The 602-foot-high structure was completed in 1945. The site is also home to the 633-MW Shasta hydroelectric plant, with five turbine-generator units.
The Shasta Dam and Reservoir Enlargement Project would provide an additional 630,000 acre-feet of water storage for the environment and for water users, Reclamation says. Enlarging the reservoir will:
- Improve water supply reliability for agricultural, municipal and industrial, and environmental uses
- Reduce flood damage
- Improve water temperatures and water quality in the Sacramento River below the dam for anadromous fish survival
Last March, Congress approved $20 million in Water Infrastructure Improvements for the Nation (WIIN) Act funding for this project, currently in the preconstruction and design phase. The total cost of the project is estimated at $1.4 billion (in 2014 dollars).
Other pre-construction activities ongoing or to be scheduled are consultations and coordination with tribal interests, land owners, government and non-government agencies; real estate planning; and arranging for a non-federal cost share partner.
Reclamation expects to issue the first construction contract for the dam raise by December 2019.
Earlier this year, Eaton announced it had received a contract to lead an electrical life extension and modernization project at the Shasta and Keswick hydroelectric power plants in California.