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After flood, rumors of dam damage
The rumors started on Friday (Sept. 17) while Hurricane Ivan’s floodwaters were raging through Jackson County.
“Did you hear?” asked the cell phone caller “The bank’s closing because Wolf Creek Dam is about to break.”
Later on that day we heard from a caller who told us we needed to investigate “the cracks in the dam at Bear Lake.” By Monday a voice on the line was telling us that “Duke (Power Co.) was really lucky Cedar Cliff Dam was still there.”
Finally, we heard via the Internet that the Bear Lake Dam was cracked and had only one pillar holding it. “Can you report on what Duke Power is planning to do about this problem?” the writer asked.
Alarmed by the mounting evidence of imminent peril, I contacted Duke Power Area Manager Fred Alexander.
I found out that Duke plans no corrective action concerning cracks in Bear Lake’s dam because there are no cracks in the dam. And, for that matter, there isn’t any damage to the dams at Wolf or Cedar Cliff either, Alexander said.
“There is absolutely no truth at all to the rumor that there are cracks in any dam,” Alexander said. “All the dams are inspected regularly by both Duke Power and a federal agency.”
During a public forum Monday night (Sept. 27) sponsored by the Watershed Association of the Tuckasegee River, Alexander used maps and diagrams to explain the seven dams and six power plants Duke operates in Jackson County along the Tuckaseigee River’s East and West forks.
He told the 30 or so people in attendance of Duke’s preparations for the storms, and how the rainfall from both Hurricanes Frances and Ivan had exceeded the East Fork reservoirs’ storage capacity.
Between Frances’ Sept. 8 departure and Ivan’s Sept. 16 arrival, Duke personnel did everything in their power to lower reservoir levels, Alexander said. They succeeded in lowering Bear, by far the largest of the four East Fork lakes, by more than 15 feet, but even that wasn’t enough to hold the stormwater, he said.
When it came time for citizen comments, one participant echoed the thoughts I’d been having. I witnessed the amount of water that poured down Wolf Creek after the torrential rains Frances delivered to the eastern end of Jackson County, and I suspected that Duke’s lakes had helped avert major flooding here.
The speaker said he was very grateful for Duke’s system of hydroelectric dams and reservoirs, which he credited with saving Jackson County from the kind of severe flooding experienced by Canton.
While there are no federal guidelines that mandate how Duke must operate its generating facilities, Alexander said the power company took extra precautions for both Frances and Ivan. Beginning Sept. 1, when forecasters first predicted that Frances might impact Western North Carolina, all of Duke’s generating plants along the Tuckaseigee operated “flat-out, 24 hours a day,” Alexander said, to increase storage capacity as much as possible.
Alexander also explained how and why excess water is released through the dam’s spillways.
When the amount of rainfall and stormwater exceeds the storage capacity of the lakes, the spillway gates must open to protect the dams, he said. Duke’s East and West Fork dams have impervious clay cores with rock and dirt on the outside and are not designed for water to flow over them.
Instead, they have float-controlled gates that open to release water when the lake level rises. In the event the spillways can’t release enough water, specially designed sections of the dams, called “fuse plugs,” will give way to protect the integrity of the main dam.
In the almost 63 years since Thorpe (Glenville) first came on line, none of the fuse plugs have given way, Alexander said.
The East and West Fork generating plants were built by the Aluminum Co. of America during the 1940s and 1950s. World War II demands for aluminum triggered Thorpe’s construction, and the Korean War and post-war boom led to the construction of Cedar Cliff, Bear, Wolf and Tanassee lakes.
Alcoa’s subsidiary, Nantahala Power and Light operated the plants and served the public utility needs of much of Jackson County. Duke bought NP&L in 1988 but the company did not formally become part of Duke until 2001.
Those seeking information about lake levels and generating history for any of Duke’s local reservoirs may access www.nantahalapower.com and click on the lakes and recreation link. For those without Internet access, similar data is available by calling toll free at 1-866-332-5253.
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