“Cumberland River Could Flood Nashville!” one headline shrieked. Suddenly, the biggest Southern tailwater no one had heard of became all anyone could talk about.

The nightmare scenario was this: a chain reaction of dam failures, starting with Wolf Creek Dam (which holds back massive Lake Cumberland), then Cordell Hull and Old Hickory Dams, sends a wall of water downriver toward Nashville. The predicted result would be 35 feet of water atop the streets of Music City for as long as 11 days. Hurricane Katrina would have nothing on a Wolf Creek Dam failure. Moreover, the threat affected every fish in a massive system--one that includes world-class trout fishing as well as trophy striped bass.

The problem? Karst.

Karst is nothing more than an especially porous type of limestone; it can crumble like a block of old Swiss cheese. Wolf Creek Dam was constructed in the 1930s and 1940s on a karst foundation, which immediately began to crumble under the weight of the dam and reservoir.

Repairs in the 1960s and 1970s held off the inevitable, but when internal moisture gauges started filling with water in 2004 and 2005, the U.S. Army Corps of Engineers took action. The solution was to partially drain Lake Cumberland to relieve pressure on the dam.

Until news of the threat made it into mainstream media, only local anglers knew about the trout fishing. But the Cumberland--like its cousin the White River in Arkansas--is a special place: one of humankind’s great accidental triumphs. What started as a flood control system now hosts what some consider the best brown trout fishery east of the Mississippi--and one of the best inland striper fisheries as well.

Some people thought a shallower reservoir would ruin the tailwater trout fishery but troubles with Wolf Creek Dam have only improved the fishing.

“It’s the South’s little sleeper,” says Ronnie “Grumpy” Howard of the Cumberland Transit Fly Shop in Nashville.

The Wolf Creek Conundrum
Historically, the tailwater below Wolf Creek Dam was a 70-mile-long, mostly coldwater system powered by six generating units. Under normal conditions, water levels could go up and down more than 8 feet in a single day.

As with the White River, these extreme variations made for big fish, but difficult fishing. Scuds, sowbugs, and midges formed the forage base, supplemented by large stoneflies as well as healthy caddis and mayfly hatches. The result was a trout paradise with plenty of food and deep water for them to hide in.

Although the tailwater is also stocked with rainbow trout by the Kentucky Department of Fish and Wildlife Resources, the real draw is the trophy brown trout fishing. Cumberland River browns can go over 30 inches, reaching sizes usually associated with lake-run specimens.

Before the Wolf Creek Dam threat, the Cumberland was primarily known as a float fishery. While many anglers did ply the waters below the dam on foot, the biggest fish were typically caught by boat anglers tossing large streamers at the banks during periods of slow generation. While a Cumberland float could be a blast, for many anglers it lacked the appeal of sight-fishing to big cruisers.

Zach Matthews is the editor of The Itinerant Angler, ( itinerantangler.com ). He lives in Atlanta, Georgia.