Guest editorial in The State, Oct 10, speaks to need for stronger water law

Guest editorial in The State, Oct 10, 2014 -- Stronger Protections needed for precious SC surface waters --

Columbia, SC — The registration that allowed a single farm to withdraw up to two-thirds of the South Fork Edisto River’s flow during low-flow conditions demonstrates the need for legislative action on state water policy.

Water withdrawals in South Carolina should be managed to minimize socioeconomic and environmental damage during periods of water shortage. Water is a precious resource, and rates of replenishment are finite and irregular. Shortages occur naturally during droughts and artificially if withdrawal rates are too high.

The population of South Carolina doubled from 2.3 million in 1960 to 4.6 million in 2010, and water withdrawals for municipal, agricultural and industrial use simultaneously increased. Increased demand increased concerns over potential shortages, and so the 2004 State Water Plan recommended establishing minimum flow requirements for streams, to be determined by the Department of Natural Resources.

The Surface Water Withdrawal Act was passed in 2010 to require water withdrawal permits. It was a positive step forward but did not provide sufficient constraints. For example, large agricultural water users are not required to obtain permits, and the potential for over-allocation has emerged as a serious issue.

The Legislature should have granted agencies charged with protection of the state’s water resources appropriate authority to exercise judgment. At a bare minimum, withdrawals should be evaluated by “reasonable use” criteria derived from common law, which have been used for centuries.

In the legal dispute over the South Fork Edisto River, Friends of the Edisto River contested DHEC’s registration, which was approved without public notification. But the law requires DHEC to approve an agricultural withdrawal if it does not cause stream flow to fall below a certain percentage of the average annual daily flow, so DHEC argued that it does not have “any discretion to decide whether or not a requested surface water withdrawal by a proposed registered surface water withdrawer will be authorized.”

In essence, the law eliminates consideration of reasonable use for farmers seeking to withdraw more than three million gallons per month. Citizens should disagree wholeheartedly with the General Assembly’s abdication of responsibility for guarding our water resources, which are held in trust for all the people of South Carolina.

Permitting should be required of agricultural water users, and the permitting criteria should be strengthened for all users. The present policy is based on a so-called safe yield, defined by long-term average flows. Unfortunately, the variability of stream flows makes defining safe yields problematic. Current law allows withdrawals of up to 80 percent of long-term average flows, even during the low-flow season. This risks acute shortfalls during droughts, when available water is well below average.

A better approach would use two criteria. The first is to limit withdrawals to only a specified percentage of available flow at a given withdrawal site, based on daily flow data, for example, limiting total surface-water withdrawals to 10 percent of the present flow. The second is to establish seasonally varying minimum flows, below which withdrawals are not allowed. These criteria should be more stringent than annually averaged yields and based on scientific evaluation of hydrologic, socioeconomic and environmental factors.

Water availability and use have high spatial, seasonal and inter-annual variability, so the limits should be revised as more information becomes available. A statewide hydrologic study is underway, including surface-water availability models that ultimately can be coupled with other water-budget information. Withdrawal limits can be changed as such studies are completed, but more stringent criteria are needed now.

As water demand rises in South Carolina, wise management is essential and should recognize high geographic, seasonal and inter-annual variability in supply and demand.

Dr. James is a river scientist and geography professor, and Dr. Tufford is a research associate professor in biological sciences at USC. Contact them at [email protected] or [email protected]