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‘Science’ backs Dillsboro Dam removal, WCU professor says
By Lynn Hotaling
A Western Carolina University professor with experience in dam removals says that removing the Dillsboro Dam would improve the health of the Tuckaseigee River.
Geologist Rob Young of Webster, who is currently a consultant on the Glines Canyon/Elwha River dam removal project in Washington state, said recently that arguments in favor of keeping the Dillsboro Dam in place are emotional rather than scientific.
“I think the benefits (of dam removal) are overwhelming,” Young said.
The professor contacted The Herald after reading in May that Webster’s town board members would likely endorse the “preferred settlement agreement” developed by Jackson County to be submitted to federal energy regulators as an alternative to the Cooperative Settlement Agreement filed by Duke Power in the company’s ongoing effort to secure new operating licenses for five of its six Jackson County generating plants.
Although both plans are complex, one significant difference is that Duke’s plan calls for the removal of the Dillsboro Dam, while Jackson County’s proposal mandates not only that the dam stay in place, but that it be turned over to the county to operate.
Young, a member of Webster’s planning board, had planned to attend the town’s June meeting to point out some of the environmental benefits of dam removal. He was unable to do so because Webster leaders approved the county plan during a called May 26 meeting in order to meet a May 27 deadline set by Jackson County for filing the plan with the Federal Energy Regulatory Commission. Young was in the Pacific Northwest working on the Elwha project when the special meeting was held.
“I really wanted to talk to people about dam removal,” he said. “I didn’t want anyone to use technical stuff as a reason to vote against the original (Cooperative Settlement) agreement.”
While part of the county’s impetus in drafting its alternate plan is that local officials say the Settlement Agreement doesn’t adequately compensate Jackson County for Duke’s use of public waterways to generate electricity, Young said he can’t comment on that.
“It’s not for me to say whether the stakeholders got the best deal,” he said.
However, looking at the plan from an environmental aspect, Young said the dam should go.
“God made the river; a power company made the dam,” Young said. “It seems that every time we have an opportunity in an economically sound way to put things right – the way they were – it’s a shame to miss that opportunity.”
Young said that while there may be sentimental reasons to keep the dam, there are not technical ones.
“If people want to say ‘keep the dam because we like it and it’s pretty,’ I can understand that,” he said. “But they can’t say ‘you can’t take it out because it will cause problems,’ because I know otherwise.”
Though he can understand the argument that the Dillsboro Dam is scenic, he doesn’t agree with it.
“To me, it would be much more attractive to have a free-flowing river.”
While the river has reached equilibrium during the 90-odd years the dam has been in place in Dillsboro, dam removal would improve fisheries, Young said. In addition to allowing fish to migrate freely upstream, dam removal would offer the fish a chance to exchange genetic material, improving the overall health of the fish population.
That opinion is supported by a study done by U.S. Fish and Wildlife, which found 29 fish species below the dam and only seven in the impounded region above the dam.
Sediment transport and potential harmful effects if the dam is removed is another issue that has been raised by those who would prefer to see the dam remain in place. In Young’s opinion, such problems would be minimal.
The two dams on the Elwha River in Olympic National Park trap a combined 18 million cubic yards of sediment, and their planned removal – endorsed by environmental agencies and the National Park Service – will be accomplished in the same manner as is planned for Dillsboro. That method involves a gradual breaching of the dam to allow monitored amounts of sediment to be flushed downstream as the river returns to its natural channel. The sediment behind the Dillsboro Dam is estimated at 100,000 cubic yards in an environmental/biological assessment conducted by Duke Power.
Both Young and visiting professor Nick Allmendinger said they would not dredge before a dam removal because in their experience a river takes only fragments of sediment at a time as it re-establishes the natural channel.
“From what I’ve seen, the sediment pretty much stayed in place,” Allmendinger said, basing his comment on work he did on removal of an old industrial dam in southeast Pennsylvania.
Dredging is not planned in advance of the Elwha dam removals (the 105-foot high Elwha and 210-foot Glines Canyon dams), Young said.
Mark Cantrell of U.S. Fish and Wildlife concurs with the specifics of Duke’s plan for removing the dam at Dillsboro.
“The Fish and Wildlife Service has evaluated the conceptual plan for removing Dillsboro Dam and believes that with close monitoring during demolition we can ensure minimal effects of sediment redistribution downstream,” Cantrell said in a recent e-mail. “This will require careful removal of sections of the dam and adjustment of stream flows. We plan to monitor suspended sediment at several points downstream of the demolition and adjust the demolition schedule if turbidity (dirt particles suspended in water) increases rapidly.
“We do not intend to allow the water clarity to be anywhere near the conditions that we saw earlier this week during the high flows,” Cantrell said. “The Tuckaseigee River receives a steady input of sediment from all of its upper watershed, especially from Scotts Creek and Savannah Creek. There is an urgent need for all Jackson County landowners to reduce and eliminate erosion from their own backyards and driveways.”
Federal power officials are expected to decide later this summer whether to allow Duke to decommission and remove the Dillsboro Dam.
Removing the dam is the linchpin of the October 2003 Cooperative Stakeholders Settlement Agreement signed by a number of local governments and agencies, including all three given “mandatory conditioning authority” by the Federal Power Act.
The power company recently received approval from the N.C. Division of Water Quality for its dam removal plan.
Removal of the Dillsboro Dam, which Duke officials say they agreed to in order to preserve generation at their larger, more efficient plants, has been the most controversial feature of Duke’s mitigation package since it was first mentioned in March 2002.
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