Holston River, South Fork Professional Review and Guide
"Weir adds life-giving oxygen to this superb tailwater. When the Tennessee Valley Authority’s 285-foot-high South Holston Dam plugged the river’s course through a low ridge in 1947 and backed water far upstream into Virginia, it created a fine tailwater fishery downstream in Tennessee. But the fishery struggled. Sure, plenty of cold water ran in the channel for more than a dozen miles down past Bluff City. It was stocked with trout, but mortality was very high and holdovers were few. The problem: Cold releases from the dam contain too little dissolved oxygen to sustain trout.
In 1991, a cooperative project involving TU, TVA, the Tennessee Wildlife Resources Agency, and others led to installation of reregulation weirs on the South Fork of the Holston, the Clinch, and the Hiwassee Rivers. The weirs are, essentially, low dams designed to retain a low reservoir of water that both maintains a stable minimum flow at times when the dams are not generating and adds oxygen via artificial plunge pool or rapids. Thanks to the weirs, these tailwaters are, indeed, year-round fisheries. The number of holdovers is increasing. And some natural propagation may be taking place. Species: Brown, rainbow. Angling methods: spin, and fly-fishing."