For more than 100 years, Duke Energy has been harnessing rivers to generate clean renewable energy. Its hydropower plants are key to the company’s long-term mission to provide sustainable energy solutions that customers value.
2018 was an especially challenging year for Duke Energy’s hydro operations team, with hurricanes Florence and Michael, followed by winter storm Diego and back-to-back rain storms in December. It contributed to one of the wettest years in almost 50 years.
For Duke Energy’s hydro system, the 2018 yearly total rainfall was 56.55 inches, 10.29 inches above the 47-year long-term average. December was the wettest December since 1971, with 8.40 inches of rain across the entire hydro system.
Because the safety of downstream residents is the company’s highest priority, the hydro team works closely with the company’s meteorologists and hydrologists to anticipate and prepare for severe weather that could affect lake levels.
The company’s 32 hydro stations and reservoirs in the Carolinas are operated from the Regulated Renewables Operations Center in Charlotte, which is staffed around the clock to manage reservoirs along the Catawba-Wateree, Yadkin-Pee Dee, Keowee-Toxaway, Broad and Nantahala rivers.
The largest lakes on the Catawba River system – Lake James, Norman and Wylie – can store substantial amounts of precipitation and runoff, which significantly reduces downstream impacts to property and public safety. With a forecast of 8 to 10 inches of rainfall in the river basin from Hurricane Florence, the hydro team aggressively moved water in advance of the storm to create additional storage capacity, lowering the three lakes as much as 4 to 5 feet over six days.
During high water and flooding conditions, Duke Energy works closely with local emergency management officials to notify and protect the public. The company also maintains a lake website with current lake level information and high-water alerts, as well as a toll-free phone line with current lake levels, special information and advisories.
Although 2018 was a challenging year for managing reservoirs, the hydro operations team succeeded at keeping reservoirs from reaching critical levels that could have resulted in evacuations or power disconnects in low-lying areas.