Hartwell, Thurmond Lakes Enter Drought Trigger Level 1

The hot weather may finally be giving way to much-anticipated fall temperatures, but it lingered long enough to cause our reservoir lakes to go into drought status.

On Thursday, the Corps of Engineers Savannah office announced that both Hartwell and Thurmond Lakes have now gone into Drought Trigger Level 1 status.

As of Monday, Hartwell Lake’s level was 656.31 ft above mean sea level – that’s four feet below full pool.

Corps spokesman Billy Birdwell says that means because of a lack of rainfall, the Corps must keep the levels in both lake balanced.

“That means that we limit the amount of water that we release from the system,” Birdwell said. “That is measured out at Thurmond Dam. We try to keep the two major reservoirs in balance with each other. We’re sending water downstream sometimes and we’re holding it back sometimes. It just depends on the inflow and the rainfall is on each of the subasins.”

Inflow, according to Birdwell, plays a critical role not only with regard to how much water is sent down stream, but also lake levels generally.

“The inflows are what really drives the reservoir levels,” he said. “Rainfall on the reservoir helps, of course, but it’s really the run-off from the streams into the reservoirs that drive the reservoir levels. And we measure it on the Broad River because it’s a major tributary going into Lake Thurmond and it’s unregulated. There are no dams on the Broad River so it gives us very accurate measurement of how much rainfall and inflow we’re getting for the basin.”

In addition, if the 28-day average stream flow at the Broad River gauge near Bell, Georgia, falls below 10 percent of normal, managers will further reduce the flow from Thurmond to a daily average of 4,000 cfs.

However, a drought trigger level 1 status does not limit recreation on the reservoirs.

While some swim beaches have limited water levels, Birdwell said camping, boating, skiing, fishing and other forms of recreation continue unabated.

The Corps expects the levels at Hartwell and Thurmond lakes to stay in drought trigger level 1 and continue their gradual decline through December.