Recent Rainfall Helps; Yet Drought Situation Remains Serious October 30, 2007
CHARLOTTE, N.C. -
In the Catawba-Wateree River basin, Duke Energy currently estimates that without substantial additional rainfall, Stage 4 drought conditions which call for tougher water restrictions may be declared in six to 10 weeks – between mid-December 2007 and mid-January 2008. The estimate was extended based upon last week’s rainfall.
Stage 4 does not mean the remaining supply of water in the basin is depleted. Rather, water suppliers would likely place additional restrictions on water use. Additional rainfall and greater water conservation could help further delay the onset of Stage 4.
Last week’s rainfall amounts ranging from 1-3 inches across the Catawba-Wateree River basin began replenishing the region’s water supply for essential drinking water, electricity and industrial needs.
Estimated Remaining Water Supply in Basin
Predicting the time until the remaining useable storage will be fully depleted is difficult due to a number of variables. The key variables are:
- Evaporation -- The rate at which water evaporates from the surface of the river and its 11 reservoirs. (This rate has fallen significantly and should continue to drop through the winter.)
- Conservation – Continued water and energy conservation has and will continue to be important.
- Rainfall – While the rainfall received during the past week is helpful, the region needs a significant amount of rainfall over the next several months to help the area recover completely from the drought situation.
Through the use of water modeling, Duke Energy has determined a worst case scenario for estimating when the usable water storage in the basin will be depleted. In that scenario, assuming a storage decline of 2 percent per week, which is the average weekly storage loss rate for the period from Aug. 27 through Oct. 19, and assuming the same rainfall/drought conditions seen in recent months, the most shallow water intakes and equipment on the lakes could begin to be impacted by the middle of March 2008.
“Although this scenario is extremely unlikely to occur, the long-term forecast through February 2008 is for drier than normal weather,” said Steve Jester, hydro licensing and lake services vice president. “According to the Climate Prediction Center, there is only a 10 percent or less probability the extreme lack of rainfall experienced in the past several months will continue. However, it’s important to understand that each of us needs to continue to conserve until more rainfall like we saw last week reaches our region.”
While this worst case scenario would not mean that the Catawba-Wateree reservoirs would be dry, it does mean the most shallow water intakes in the basin could be at risk at that time and contingency plans would need to be implemented to ensure essential needs are met.
Duke Energy Actions
Since April, Duke Energy has reduced hydroelectric operations by more than 50 percent in order to save water. Hydroelectric, coal and nuclear plants on the Catawba lakes generate approximately 9,000 megawatts of electricity for Duke Energy’s customers in the Carolinas.
Duke Energy built 11 lakes on the Catawba to help provide vital electricity to more than 2.2 million customers in the Carolinas.
“Duke Energy is committed to being a good steward of the lakes it built,” Jester said. “Besides providing water for drinking and other purposes, these lakes contribute other essential services to communities in the region, including drought management.
“In the Catawba-Wateree River basin, we’re fortunate to have 11 dams to help manage the flow of water. Many free flowing creeks and streams have already dried up,” Jester said.
In addition, Duke Energy has worked for months with 24 major public water system operators as part of a drought management team. The team has shared extensive data about the drought situation and coordinated efforts to conserve water in the basin. This regional approach has resulted in more than 20 percent water savings through conservation efforts.
Major Water Suppliers’ Next Steps
As part of the regional approach to ensuring water remains available for essential water use, owners of water intakes in the Catawba-Wateree River basin are finalizing contingency planning in order to protect the water supply.
Residents should contact their local water supplier with any questions about their drinking water.
By reducing our individual water use we can help buy more time until needed rainfall can arrive in the region. Since power plants use water in their operations, it’s important to conserve both water and electricity.
Visit Duke Energy’s Carolinas Drought Information website at www.duke-energy.com/lakes/carolinas-drought-info.asp for the latest information about water and energy conservation tips, lake levels and boat ramp closings.
Duke Energy's Carolinas’ operations include nuclear, coal-fired, natural gas and hydroelectric generation. That diverse fuel mix provides nearly 21,000 megawatts of safe, reliable and competitively priced electricity to more than 2.3 million electric customers in a 24,000-square-mile service area of North Carolina and South Carolina.
Duke Energy, one of the largest electric power companies in the United States, supplies and delivers energy to approximately 4 million U.S. customers. The company has approximately 37,000 megawatts of electric generating capacity in the Midwest and the Carolinas, and natural gas distribution services in Ohio and Kentucky. In addition, Duke Energy has more than 4,000 megawatts of electric generation in Latin America, and is a joint-venture partner in a U.S. real estate company.
Headquartered in Charlotte, N.C., Duke Energy is a Fortune 500 company traded on the New York Stock Exchange under the symbol DUK. More information about the company is available on the Internet at: www.duke-energy.com.