Dam going, nature returning

BROWNSVILLE, Ky. – A project decades in the planning started with a bang – and that’s in the literal sense.

On Tuesday, March 28, a large yellow machine with a pile driver affixed to its arm clanked onto the concrete shoulder of lock and dam No. 6 on the Green River. Its operator lifted the driver, a slender length of steel ending in a point. He aimed it at a spot where workers had toiled to build a wall a century earlier.

Bang!

Thus did the first step in a project to restore the Green to its natural boundaries begin. It likely will continue for a couple of weeks until the dam is gone, the water flows freely again.

Heavy machinery breaking down the concrete dam. Video by Mark Davis, USFWS.

The U.S. Fish and Wildlife Service (the Service) is conducting the demolition. The U.S. Army Corps of Engineers, which oversees the structure, is assisting.

Removing the dam will lower water levels in Mammoth Cave National Park, just upstream. That will restore a healthier habitat for fish and freshwater mussels, some endangered. Proponents are sure anglers, boaters and others will enjoy a free-flowing river, too.

For the Service, the $870,000 project is just another in a growing list of dam-removal jobs. A team of equipment operators in the Service’s Fisheries and Aquatic Conservation division is taking apart the 220-foot-long dam, chunk by chunk. The crew has worked across much of the Southeastern United States to restore waterways to their natural state.

“Today is a good day for the Green River,” said Cindy Dohner, director of the Service’s Southeast region. The region includes Kentucky.

“It’s also a good day for Kentuckians and everyone who enjoys this river,” said Dohner, whose staff worked with the Corps, the Kentucky Department of Fish and Wildlife and the Nature Conservancy to demolish the structure. “Restoring the river to its natural flows makes sense.”

The lock and dam were built in 1904 to enhance commercial traffic on the upper stretch of the Green River. It was one of six that eventually stretched across the 384-mile stream. The facility closed in 1950. It had long been on officials’ watch list as a structure that should be removed.

A heavy machinery jack hammer works on a concrete dam.

Shot through the aged remains of a wooden barrier adjacent to lock No. 6. Photo by Mark Davis, USFWS.

The dam and lock effectively moved to the top of the list in November, when the Corps discovered a hole in the dam’s foundation. It created swift currents, a potential hazard to boaters, as well as altered water levels in Mammoth Cave and beyond.

Federal officials knew: It was time to act.

Demolishing the dam here helps restore the Green to its natural diversity, said Mike Turner, chief of environmental resources for the Corps’ Louisville district. Turner, who oversaw the project from drawing board to demolition day, said the removal has “multiple benefits” – starting with making the site safer.

“Anyone drawn into this (the hole under the dam) would have no hope of survival,” he said.

An ancient waterway

The river’s name is apt. It tumbles in a green diagonal across south-central Kentucky, arriving at the Ohio River. It’s the most biologically diverse river in the Ohio River basin.

It is ancient, older than memory. Bison grazed near its banks. Mountain lions crept to its shallows to drink. Untold generations of Native Americans fished its waters. Veterans of the Revolutionary War laid claims to tracts hard on the river’s edge.

A bright red no trespassing sign in the woods.

No Trespassing! Photo by Mark Davis, USFWS.

In the mid-19th century, industrialists took an interest in the river, too. Over the course of about 70 years, locks and dams took shape along the river. Now, two are left.

“The restoration should be rapid,” said David Phemister, Kentucky State director of The Nature Conservancy. The morning of March 28 found Phemister on the river’s banks, smiling while an array of machines growled and banged at the dam.

“It’s a win for the health of the river,” he said. “We’re going to see great benefits for freshwater mussels, as well as for freshwater fish.”

The project’s debris – there will be tons of it – will be stored in the former lock chamber, where long-ago stevedores altered water levels to allow craft to bypass the dam.

When it’s done, the place where a dam once stretched will feature a rocky shoreline. The river will roll past it, unimpeded and wild.

Multimedia from the event

Contact

Mark Davis, Public Affairs Specialist
mark_r_davis@fws.gov, (404) 679 7291