“It’s like Niagara Falls for Augusta,” said Beverly Cullipher, who joined an estimated 1,000 spectators who picnicked, took photos and socialized while enjoying the view – and the roar of falling water – during the two-hour gate test.
“It was well worth the walk,” said Ryan Tripp, of Aiken, who took time off work to take his three sons – Ben, Brayden and Barrett – to the Below Dam recreation area to enjoy the show.
The Army Corps of Engineers opened 22 of the dam’s 23 spillway gates from one to two feet apiece to make sure the recently renovated gates perform properly should an emergency release of water be required. The gates are designed to open more than 20 feet.
Although the falling water offered a spectacular view, it did not add to the volume of floodwaters already flowing downstream toward Augusta.
The dam’s seven hydropower turbines have been generating large volumes of electricity with excess water from recent rains, but six of those turbines were shut down while the gate test was underway, corps spokesman Billy Birdwell said.
The net effect was actually a small decrease in river flow during the gate tests, he said, but the flow increased again when the gates were closed and the turbines resumed operation.
The test was the first time in more than six years the gates have been opened. Similar tests were conducted this week at lakes Hartwell and Russell, but those events didn’t draw nearly the crowds that gathered at Thurmond Lake.
“We had about 400 people at the Hartwell test and about 200 at Russell,” Birdwell said.
Although the lakes have been well below full pool in recent years because of long droughts, the corps has occasionally needed to open the gates for emergency water releases.
On Feb. 7, 1998, for example, heavy winter rains pushed Thurmond Lake up to 335.57 feet above sea level – more than five feet above full pool – prompting an emergency opening of all 23 spillway gates.
Corps officials estimate it will take from 18 to 45 days before the lake is reduced to its normal full pool of 330 feet.
The river continued to swell downstream, where boat ramps, parks, marinas and sections of Riverwalk Augusta were inundated and closed.
According to the U.S. Geologic Survey’s monitoring gauges below Augusta, the river’s flow was more than 47,000 cubic feet per second on Thursday afternoon, and the pool level was approaching 118 feet above sea level – or the official flood stage.