Why We Work

The Clinch-Powell Rivers are a globally important “Cradle of Aquatic Diversity”

Due to their ancient geology and isolation, the Clinch and Powell watersheds have been called a “cradle of diversity” for aquatic fauna in the southern Appalachians.stream

At least 17 mussel species inhabiting these waters appear on the federal endangered species list. And in the context of the entire temperate world, the Clinch-Powell system ranks as one of the top two in terms of biological richness.

    • The Clinch-Powell river system supports more than half of the native fish species currently in the Tennessee drainage, including 14 species that are found only in the upper Tennessee River basin and nowhere else in the world.
    • At least 48 freshwater mussel species inhabit the Clinch Valley region, and many globally rare species’ strongest remaining populations are located here, including four species that occur only in the Clinch and Powell rivers.
Healthy mussels mean healthy rivers to meet human needs.

Freshwater mussels provide valuable ecological services such as helping keep the water clean, supporting healthy aquatic communities, improving water quality and balancing food webs:3oct07-Wallens-Bend-Clinch-Rvr-JL-395

    • Mussels Purify Water for Free!One mussel can filter from 0.5 to1.25 gallons of water per hour. Therefore, a large healthy mussel shoal with high densities canfilter much of the river flow. Such a shoal at Brooks Island (with as many as 1 million mussels) on the Clinch River, just above the water intake of Sneedville, Tennessee, can filter 12 million gallons per day.
    • Mussels Are Natural Pollution Monitors. Mussels are excellent indicators of water quality. Mussels are long-lived, soak up particular contaminants, and can serve as a record of pollution.
    • Mussels Improve Fishing. Mussels create beneficial habitat for the animals that fish eat.
But many of these unique aquatic species are in trouble.
    • mussels species
      Endangered freshwater mussels in the Clinch and Powell River Watersheds in Virginia (Bottom diagonal row, left to right: Cumberlandian combshell, Oyster mussel. Middle Row: Shiny pigtoe, Birdwing pearlymussel, Cumberland monkeyface. Top row: Rough rabitsfoot). Photo courtesy of USFWS.

      Data collected by researchers over the past 30 years reveal patterns of decline among freshwater mussel species in the Powell River and in several significant reaches of the Clinch River system.

    • Of the 60 mussel species once documented, at least 11 are now considered extinct or extirpated (gone from these rivers), 29 are considered imperiled (in jeopardy of extinction), and 18 are listed federally as endangered.
    • Five fish species are thought to be extinct or extirpated, and 19 fish species are imperiled.