In the late 1920s, Thomas Williams and William S. Murray had an idea: a hydroelectric power plant in the middle of South Carolina.

That idea turned into a reality, now officially known as the Dreher Shoals Dam and more frequently called the Saluda Dam (after the river it plugs up) or the Lake Murray Dam (after the 41-milelong, 14-mile-wide lake named after one of the dam’s lead engineers, William Murray).

On Nov. 10, Billy Chastain — director of lake management at Dominion Energy, which owns and operates the Saluda Hydroelectric Plant and oversees land use and shoreline management around Lake Murray — was the guest speaker at the Irmo Chamber Luncheon. He presented some interesting points about the history of the dam.

The first load of dirt was put in place with the latest technology, steam-powered shovels, on Sept. 21, 1927. In August 1929, the river diversion tunnel was closed to fill up the new lake. History was made, as what was then the world’s largest earthen dam was completed.

Completed in 1930, the 1.5-mile-long dam was 208 feet high. Today, after receiving upgrades in the intervening years, it produces more than six times as much power as it did when it began operation.

Chastain said the maximum amount of water released at the spillway can flow at 18,000 cubic feet per second. The spillway has been opened twice in the history of the dam, in 1969 and during the Midlands’ historic flooding in 2015. The 50,000-acre lake cannot get over a surface elevation of 360 feet at the shoreline. During the 2015 flood, the lake approached 359.9 feet. On Oct. 4, 2015, the spillway was opened to relieve the pressure of the water.

According to Chastain, the first boat to enjoy the lake was a mosquito control boat. The boat’s purpose was to spray kerosene on the lake to kill the mosquitoes.

Lake Murray touches four counties — Lexington, Newberry, Saluda and Richland counties — and currently has 14,000 docks.

The backup dam behind the original earthen construction was started in 2001 and finished in 2005. The granite rock it was built with came from the quarry on site.