By Tracy Robillard, Public Affairs Specialist
Due to recent increased rainfall throughout the Savannah River Basin and upcoming weather forecasts, water managers with the U.S. Army Corps of Engineers Savannah District issued a revised declaration on July 11.
The good news is that Tropical Storm Chantal has degenerated, and the National Weather Service is no longer forecasting heavy rainfall in the basin due to that storm system. The 7-day forecast suggests between 1 to 1.5 inches of rainfall over the upper part of the basin, and 2 to 3 inches in the lower basin near Savannah.
Our revised declaration lowers outflows from the Thurmond Dam from 37,000 cfs to 33,200 cfs. It also calls for outflows at the Hartwell and Russell dams this weekend: 6,800 cfs at Hartwell and 13,000 cfs at Russell. Normally we don’t release at Hartwell and Russell and Saturdays and Sundays, but we are releasing this weekend to keep the reservoirs from raising any further based on inflows.
Over the next several weeks we aim to bring the reservoirs back down to guide curve, or “full pool” in accordance with our water control manual. Guide curve for this time of year is 660 ft-msl at Hartwell, 475 ft-msl at Russell, and 330 ft-msl at Thurmond. If higher-than-average rainfall continues, it could take anywhere from 14 to 45 days or more to reach guide curve at all three reservoirs.