Moderate drought declared for Savannah River Basin
State and local Drought Response Committee members declared a “moderate” drought for the Savannah River Basin during a meeting Wednesday, September 20, 2006, in Columbia based on the hydrologic conditions in the basin. The state agency members of the drought response committee voted to declare a moderate drought in Oconee, Pickens, Anderson, Abbeville, McCormick, Edgefield, Aiken, Barnwell, Allendale, Hampton and Jasper Counties.
The state agency representatives of the drought response committee declared an incipient drought on August 16, 2006. Recent rains have not improved the hydrologic conditions with lake levels continuing to decline. The U.S Army Corps of Engineers upgraded the drought status for the Savannah River Basin to the second stage of drought on August 28, 2006.
Moderate drought means there is an increasing threat of a drought as demonstrated by drought indices. The primary indices driving this declaration were the sustained decline in reservoir levels and decline in ground water resources.
“The decision to upgrade the drought status to moderate was supported by the long-term rainfall deficit in the Upstate,” said Freddy Vang, DNR deputy director of the Land, Water and Conservation Division. “What we need to see is a significant change in rainfall over the next 60 days and beyond, otherwise, the streams and lake levels along the Savannah will continue to decline.”
According to Hope Mizzell, South Carolina state climatologist, the U.S Army Corps drought designations and what Duke Energy is observing in the basin were the primary factors influencing the State and Local Drought Response Committee’s decision to upgrade. On the Savannah, Lake Hartwell and Lake Thurmond have reached drought trigger level two, according to the U.S. Army Corps of Engineers Drought Plan. Mr. Vang adds, “The U.S. Army Corps of Engineers and Duke Energy have been working together to manage and conserve water levels in the basin. This is not an easy task given the long-term rainfall deficit. The SC Drought Response Committee’s decision to upgrade to the second level of drought demonstrates that consistency between local, state, and federal drought response is important for effective drought planning and management.
Bud Badr, State Hydrologist, explains, “The U.S. Army Corps of Engineers drought level two recommends a water release of 4,500 cfs [cubic feet per second] downstream from Lake Thurmond; however, because of the persistent drought conditions in the basin the U.S. Army Corps of Engineers has only been releasing 3,600 cfs for the last 10 days. 3,600 cfs is the lowest that can be released without negative impacts for downstream users. By reducing releases now they are extending the availability of water in the reservoirs.
Fortunately, according to David Baize with the S.C. Department of Health and Environmental Control, no water systems are reporting any supply problems at this time. Hope Mizzell explained that the moderate declaration does not require any mandatory action by public water systems or the public, but all water systems in the Savannah should take the opportunity to review their local drought plans and ordinances and where needed implement accordingly.