J. Strom Thurmond Dam

In 1890, Lieutenant Oberlin M. Carter of the U.S. Army Corps of Engineers (USACE) Savannah Office issued a survey report that recommended the construction of dams on the Savannah River in order to prevent flooding in Augusta, Georgia. His report was overlooked until the 1927 Rivers and Harbors Act allowed the USACE to investigate development of the Savannah River for the purpose of hydroelectricity, navigation, flood control and irrigation. In 1933, the USACE completed the report for the entire Savannah River Basin that recommended against government flood control development of the basin but did propose two hydropower dams in the upper Savannah Basin, the Clark Hill and Hartwell Dams.[2]

Construction on the Clarks Hill project was not authorized until 1944 by the 78th Congress and prior efforts by local leaders in Augusta were instrumental in gaining approval. Support from the USACE along with Georgia Senators Walter F. George and Richard Russell and Georgia Congressman Paul Brown were important towards getting President Franklin D. Roosevelt's blessing in a 1935 plan. Roosevelt ordered a feasibility study to be done on the Clark Hill Project amongst other dams in the plan. The results were sent back to the President in 1937 and other reviews were conducted until focus on the Second World War slowed the approval process. The next comprehensive study on the Upper Savannah Basin was not completed until 1943 but the project was authorized by Congress with Public Law 534 in 1944. A clerical error at the time named the project "Clark Hill" instead of "Clarks Hill". The final report on the Upper Savannah Basin was issued in 1946 and initial construction began soon thereafter on August 1.[2]

Construction was at first ceased until November 1946 as President Harry S. Truman had halted funding for many government programs in order to handle a post-Second World War depressed economy. In 1947, diversion of the Savannah River and construction of a coffer dam began while the contract for the actual dam was awarded. The construction plant for the dam was also completed in 1947, containing equipment to create concrete that would be transported anywhere on the construction site via three-revolving gantry cranes with 124 ft. booms. In 1948, after the foundation was excavated, workers began to pour concrete on site for the spillway. In 1949, initial work on the concrete spillway was completed; the original coffer dam was removed and a second cofferdam was installed in order to restore the flow of the Savannah River to its original channel but now through eight-sluice gates in the spillway structure. Concrete operations on the main part of the dam had halted in 1949 because of a steel-strike but resumed in 1950 and much of the spillway was completed by the end of the year.[2]

In late 1950, contracts for construction of the powerhouse were awarded and the contracts for the 7 generators had been awarded a year prior. Construction on the powerhouse would lag initially because materials were needed for the Korean War but by July 1952, 60% of the powerhouse was complete. Each generator required for the power house needed 32 railcars to transport on site. By July 1951, the reservoir began to fill as most of the embankment part of the dam was complete and filling would finish in October 1952. By November 1952, the first generator was operating and began transferring power to South Carolina early the next year. The six remaining generators went online between 1953 and 1954. The project was completed at a cost of US $78.5 million compared to the estimated cost of US $35.3 million in 1944.[2]

Since completion, the J. Strom Thurmond dam has prevented an estimated $185,000 annually in flood damages. In one specific case, the dam decreased the height of the March 1964 flood from 38 feet (12 m) to 25 feet (7.6 m) at Augusta, where the flood stage is 32 feet (9.8 m). The dam also helps maintain the 9-foot (2.7 m) navigation channel near Augusta along with reducing silt in the channel by 22%.[2]

Power plant

The J. Strom Thurmond Dam's power-house is a concrete-gravity structure that is flanked by embankment dams for a total length of one mile. The concrete section is 1,096 feet (334 m) long and is 200 feet (61 m) high from the Savannah's thalweg. The dam created the 71,000-acre (29,000 ha) Lake Strom Thurmond which stretches 29.4 miles (47.3 km) up the Savannah River and 17 miles (27 km) up the Little River. The dam is 239.5 miles (385.4 km) upstream of the Savannah's mouth and combines with the Hartwell Dam (1962) and the Richard B. Russell Dam (1985) in order to form over 120 miles (190 km) of lakes.[5]

The dam helps provide electricity during peak-hours with seven 40-MW hydroelectricity generators. Each turbine weighs 300 tons and has a 30-foot (9.1 m) diameter. The generators are fed with water by seven 214-foot (65 m), 20-inch-wide (510 mm) penstocks, and the dam's spillway contains 23 tainter gates that help maintaining a normal 330 ft MSL lake elevation and flooding. The dam's 700,000,000 kW·h annual production of electricity is managed by the Southeastern Power Administration[5]

Electricity from the dam is marketed by the Southeastern Power Administration.[6]

• List of dams and reservoirs in Georgia
• List of dams and reservoirs in South Carolina

Wikimedia Commons has media related to J. Strom Thurmond Dam.

• USACE J. Strom Thurmond Dam and Lake