Developers are increasingly damming up streams to create ponds for aesthetics. Some mega developments are going a step further and building full-blown lakes.
“These impoundments are a little-noticed facet of the region’s increasing development, but they have serious and near-permanent impacts on the streams where they’re built,” said Bryan Tompkins, a biologist with the U.S. Fish and Wildlife Service. “Nothing changes the nature of a stream as directly or profoundly as damming it.”
Developers who want to dam up a creek must get an environmental permit first. There has been an increase in dam permit applications in WNC. Five dam applications have been submitted so far this year that collectively would claim three miles of free-flowing streams by turning them into ponds and lakes.
Tompkins said each dam is “chipping away at the beauty and natural heritage of our free-flowing streams.” Ponds and lakes are not a natural part of the WNC ecosystem.
Native fish and other aquatic life are adapted to cold, fast-moving streams with lots of oxygen. When a dam brings a stream to a near standstill, the standing water warms up in the sun and the water’s oxygen level drops — altering water quality not only for the dammed section but downstream as well. The dammed section is no longer suitable for native fish and aquatic wildlife and keeps fish from moving upstream and downstream to breed.
“People are attracted to this area for its natural beauty, but lakes are not a natural feature of the Southern Appalachians — every lake in the region was created by humans and they’ve each had an adverse impact on our streams,” said Tompkins. “Once you turn a mountain stream into an impoundment, you’ve lost something that would take a lot of money and time to restore.”
Damming a stream requires permits from the U.S. Army Corps of Engineers and the N.C. Division of Water Quality. U.S. Fish and Wildlife routinely weighs in on these permits.
While most artificial lakes are for aesthetic enhancement, others have more colorful proposed uses. A developer in Catawba County wants to create a lake for water skiing. A developer in Caldwell County wants a 160-acre lake to be used as a seaplane landing area, despite the presence of an airport five miles away.
“The developer expects 10 to 12 planes to use the lake. I question whether that’s worth the resulting destruction of nearly four miles of stream,” said Tompkins.
The U.S. Fish and Wildlife Service opposed a dam permit in Transylvania County last year to create a 15-acre lake as part of a subdivision abutting the Pisgah National Forest. The dam would have bisected habitat for Southern Appalachian brook trout, leaving the isolated populations on either side of the dam potentially too low to survive.
“The presence of our native brook trout played a large role in the denial of the permit, but there are a lot of other streams that don’t have brook trout that are being permanently altered,” said Tompkins.
There is one compromise solution, Tompkins said. Developers can create the pond by diverting a portion of the stream over to one side — rather than imposing the pond over the top of stream — leaving the main stream branch intact.
“The impacts are far less,” Tompkins said.
Public comment is accepted for all permits. To find out what applications are up for review, go to www.saw.usace.army.mil/wetlands/notices.html.