Georgia aquifers could provide more water

Georgia's coastal plain aquifers could provide more water than current withdrawals demand, according to a new study prepared for the state's regional water planning councils.

State Geologist Jim Kennedy, speaking Tuesday during a joint meeting of five regional councils, said the model devised to evaluate groundwater resources shows the region could produce a sustainable yield of 1,066 to 1,229 million gallons a day -- compared to an estimated current pumping of 667 million gallons a day.

He cautioned, however, that anytime water is pumped from the series of subterranean aquifers, it has definite impacts.

"It's a varied system, and all the pieces are speaking to each other," he said.

Pumping increases the rate of recharge from surface streams and nearby aquifers, he said, and the removal of water from certain areas can lower underground water tables, which in turn can reduce the amount of water discharged from aquifers into streams, other aquifers and even the ocean.

The study is one of several undertaken by Georgia officials working to develop a Comprehensive Statewide Water Management Plan that will help guide future water use priorities.

While the groundwater study found ample supplies in most areas, notable exceptions included coastal areas affected by saltwater intrusion, including Savannah, and selected areas in the lower portion of the Flint River Basin, which are already subject to special permitting provisions.

Kennedy also acknowledged that changes in groundwater use in portions of South Carolina might affect Georgia's projections.

A similar study found that the Savannah River Basin has ample water to satisfy existing flow and usage demands -- with enough storage in major reservoirs to survive even the most critical droughts. Flows in the Ogeechee River Basin, by comparison, were insufficient to meet existing demands during drought conditions.

The water councils represented Tuesday included the Savannah-Upper Ogeechee, led by Columbia County Commission Chairman Ron Cross; and the Coastal, Altamaha, Suwanee-Satilla and Upper Oconee.

Reach Rob Pavey at (706) 868-1222, ext. 119, or rob.pavey@augustachronicle.com.