Coal Mining Drives Decline of Freshwater Fish

Greg Buppert, Staff Attorney

Endangered mussels being tagged and placed in the Powell River in Tennessee. ©Gary Peeples/USFWS

Most folks know that Tennessee is home to great music, the Smoky Mountains, and Andrew Jackson. What they probably don’t know is that the state is also the epicenter of freshwater aquatic biodiversity in the U.S. — its rivers, creeks, and wetlands provide habitat for more than 300 species of fish, 125 species of mussels, and 75 species of crayfish. Sadly, Tennessee’s aquatic habitats and species, and those of the Southeast in general, are among the planet’s most imperiled. According to the American Fisheries Society, more than 70 percent of the region’s mussels, 48 percent of its crayfishes, and 28 percent of its fishes are endangered, threatened, or identified as species of special concern. Mining, dams, development, logging, agriculture, and climate change are the prominent obstacles to freshwater conservation, but the threats are myriad and increasing.

Surface coal mining — prevalent at a gigantic scale in West Virginia, Virginia, Kentucky, Tennessee, and Alabama—is especially destructive for freshwater life. Surface mining requires the removal of large tracts of dense Appalachian forests, permanently disrupting the gentle percolation of water through the forest floor that forms headwater streams. Without the buffer of the forest to soak up rainfall and snowmelt, streams in mined watersheds receive greater and more intense runoff, and in turn, downstream floods are more frequent and more destructive. Mining’s disruption of the water cycle cripples the vital processes that headwater streams perform in a freshwater ecosystem, like fueling the downstream food web with organic material.

A creek in West Virginia, polluted by mine runoff. ©Elias Schewel

Surface coal mining also exposes virgin bedrock to the elements, triggering a weathering process that contaminates stream waters with toxic metals and salts. Mining operations blast away entire mountain tops to reach coal seams that may be only two feet thick and dump massive rubble piles into nearby valleys. Streams are buried, and in some cases, most headwaters in a watershed are entombed in mine rubble. As metals and salts leach from the newly exposed bedrock, the chemistry of stream waters becomes increasingly toxic to aquatic life. Certain metals like selenium are concentrated at especially harmful levels as they move through the food chain. Not surprisingly, biodiversity suffers marked declines following the onset of surface mining.

Attempts to restore abandoned mining lands offer little hope for the recovery of aquatic life; reclaimed lands cannot replace the ecological functions of undisturbed forests and headwaters. Evidence suggests that the return to a natural system may be hundreds or even thousands of years in the future. Surface mining also impacts an area significantly greater than the footprint of the mine itself. A recent study by scientists at Duke University confirmed that, while mines occupied approximately five percent of the land area in southern West Virginia, they caused steep declines in aquatic biodiversity in more than 22 percent of the region’s streams.

Most mining lands in the Southeast are privately owned, and the region’s freshwater species and habitats are some of the least protected in the U.S. Though the Clean Water Act, the Endangered Species Act, and other federal environmental laws provide tools to protect aquatic ecosystems, state and federal agencies have, in general, failed to implement these laws strenuously enough to reverse the decline of the region’s water quality. In the case of surface coal mines, the best hope for species and habitat protection often amounts to nothing more than a sternly-worded letter from the EPA that the permitting agencies simply ignore.

Cumberland darter, ©USFWS

Defenders is working to find a legal foothold to increase the protection of freshwater species in the Southeast. Together with the Sierra Club, Tennessee Clean Water Network and SOCM, we are exploring strategies to address the impacts of surface mining on endangered and threatened fish in Tennessee. The northern Cumberland Plateau is home to many surface mines and two fish listed under the Endangered Species Act: the blackside dace and Cumberland darter. These species are especially vulnerable to coal mining’s impacts on water quality, and entire populations have disappeared after mining operations began in occupied watersheds. Without intervention, surface coal mining will continue to push these species towards extinction. We’ll keep you posted on our work in Tennessee, and hopefully make real progress for cleaning up the water in the southeastern U.S.