I work in a number of beautiful streams in southwest Virginia and northeast Tennessee as part of my job with FMCC. This is one of those streams, the Powell River. The Powell flows southwest from the mountains of Virginia to Norris Lake in Tennessee. It is a third to fourth order stream. Where we work, substrate mostly consists of loose sands and gravel and some cobble. It is very remote and has mountains all around. It once was a major tributary of the Clinch River until the dam flooded their confluence in the mid 1930's.
Humans have not only dammed the Powell, but also used it as transportation for coal they mined out of the mountains. Being so remote, coal miners had no access roads to certain mines along the river. So, in order to transport their treasure they would pour it into the water and collect it at shallow fords downstream. You can imagine what this did to local aquatic wildlife populations (especially those that were benthic). The river to this day is still known to run completely black with coal fines during high flow events. Fortunately, a large number of fish and mussels populations have been able to persist. It is still unknown what kinds of chronic problems this is causing to wildlife populations in the river. This is one of our mussel holding pens and you can see how coal particles have covered other substrates in just a matter of weeks.
As part of the upper Tennessee river system, the Powell likely was once home to as many 45 mussels species. Now it is home to about half that, and many are endangered species. Some species were extirpated due to the fact that their specific host fish (the paddlefish) could no longer migrate upstream to them due to the dam. This is an Appalachain Monkeyface found at a site on the Powell. This river is home to the only remaining population of this species left on earth and it is estimated that their numbers are in the hundreds.
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