Power plants along the Catawba River are creating an inordinate amount of stress on the water and region, according to a report published last week.
Union of Concerned Scientists last week released "Freshwater Use by U.S. Power Plants: Electricity's Thirst for a Precious Resource," listing the Upper Catawba and South Fork of the Catawba among the hardest hit watersheds nationwide by water withdrawals for power plants.
"The Catawba River basin is one of 25 basins in the country where power plants are the major driver of stress on the region," said Peter Frumhoff, director of science and policy for Union of Concerned Scientists. The union is a nonprofit science advocacy group
The authors defined stress as the amount of water being withdrawn, and the temperature it reaches before being released. High temperature can have negative impacts on wildlife and ecosystems, while quantity losses create "increasing competition" for water. The entire Southeast showed stress, with the report finding that power plants in the region withdraw close to 40 times as much water per unit of energy created compared with others such as the Southwest.
"It is concerning us that the Southeast is facing a much different future," said Ulla-Britt Reeves, regional program director for Southern Alliance for Clean Energy. "We can no longer rely on the Southeast being flush with water."
The report said Duke Energy, the company managing power plants along the Catawba River, including Lake Wylie, has the largest "withdrawal intensity" of the 15 largest electric utilities, Reeves said. A Duke study projects that by 2048, the demand on the Catawba will exceed its yield. Groups such as the Catawba-Wateree River Basin Advisory Commission, Catawba-Wateree Drought Management Advisory Group and others are studying the issue.
"Our water and energy demands will collide," said David Merryman with the Catawba Riverkeeper Foundation. "If we all intend to keep using the Catawba River, we'd better act now."
In a statement, Duke said some of the issues in the report are being addressed.
The company is building two natural gas, combined-cycle plants in North Carolina, retiring nearly 3,800 megawatts of older, coal-fired generation. The company said it continues to seek "a diverse array" of energy options while balancing the need for consistent power for customers.
On other points, Duke disagrees with the report.
The findings do not note the voluntary implementation of a basin-wide drought response, spurred by Duke's federal hydroelectric relicensing effort, that saved more than 1 trillion gallons of water during the record 2007-2008 drought and "preventing a true water emergency." Or that the same effort created a basin-wide water management group already working to extend that 2048 deadline.
"Duke Energy remains committed to providing service to customers reliably, affordably and in increasingly clean ways," according to the company's statement. "Some of the recommendations in the report, such as switching to dry or hybrid cooling methods, have significant disadvantages and would not be in the best interests of our customers."
Duke said its plants should be graded on water consumed, not water withdrawn. Once-through plants, where cooling water is returned to its original body of water, supply back 99 percent of withdrawals without temperature increases beyond what regulations allow. Closed-cycle systems such as the one used at Catawba Nuclear Station withdraw much lower volumes of water but consume 30 to 40 percent more overall since the water is released back as steam.