Southeastern Fishes Council
In the News
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Dam to Disappear
March 26, 2003
Release from:
By Rusty Dennen
The Free Lance-Star Publishing Co. of Fredericksburg, Va.
If all goes according to plan, the first section of the Embrey Dam will come down early next year.
Rappahannock will flow unobstructed
SOMETIME NEXT February, if all goes according to plan, explosives will be placed along a 200-foot section of the Embrey Dam.
A controlled blast will breach the concrete structure, opening up the Rappahannock River above the dam to migrating fish for the first time since the mid-1800s.
But before that can happen, a vast shoal of sediment that has piled up behind the dam, off Fall Hill Avenue, must be removed.
By the end of 2006, all remnants of the dam will be gone. It will become a footnote in Fredericksburg's history. Meantime, the dam project--with a $10 million price tag--will become the most expensive demolition project ever attempted here.
It's really three jobs in one: dredging, removing the Embrey Dam, and dismantling an 1854-vintage crib dam buried behind it.
Bids were opened Tuesday for the dredging work, according to Brian Rheinhart, project manager for the U.S. Army Corps of Engineers office in Norfolk. There were four bids, ranging from $2.6 million to $5.8 million. The low bid is within the project's budget, Rheinhart said, adding that one of the proposals will be accepted within the next two weeks.
As dam projects go, this one "is very unique," Rheinhart said. One reason is the sheer size of the structure. It's over 1,000 feet long, including the abutments, and 22 feet high. Silt has been piling up behind it for almost a century, and the crib dam running parallel to Embrey Dam is of historical interest.
Timing is another issue: No demolition work can be done from March through June, when fish such as shad and herring return to the Rappahannock to spawn.
Moving a mountain
The first contract to be awarded will be for the preparation of a disposal area on land adjacent to the river. That site will hold a mountain of sediment dredged from behind the dam.
Fredericksburg officials recently completed a deal to buy 48 acres from the Silver Cos. for that purpose. About 13 acres of the site will be affected.
An initial estimate of the amount of silt was over 500,000 cubic yards, but Rheinhart said it's actually about half that much.
Workers aboard a floating platform with a powerful pump will suck the silt from the river bottom with a vacuum-like attachment, and send it through a floating pipe and up the riverbank to the disposal area.
The solids will settle out in the containment area, and the water will be recycled back into the river. The sediment has been analyzed and found to contain no harmful chemicals, Rheinhart said.
"It's about two-thirds sand and one-third silt," he said, adding, "It's going to be challenging to get the sediment removed in this short period of time."
He estimates it will fill a space 650 feet by 575 feet--about one-third the area of Spotsylvania Mall--to a depth of about 40 feet. Later, as it dries, the sediment will have a soil-like consistency and can be graded and seeded.
With dredging completed by the end of the year, the next step is actual removal of the dam.
The initial breach would be done in February. The corps wants to use an Air Force Reserve demolition team to place the explosives and remove a 200-foot section of the Embrey and crib dams.
The breach "will probably be more toward the north [Stafford County] side," Rheinhart said. "We're trying to locate it in the center of the natural channel of the river" to make the easiest passage for migrating fish.
The opening will lower the river water level to expose the crib dam, which will be studied by archaeologists with the Virginia Department of Historic Resources next year between March 1 and June 30.
Next summer, a causeway--possibly using some of the dredged material--will be built into the river and the remaining concrete from the Embrey Dam, as well as the rest of the crib dam, will be removed.
"Most likely, that will be by mechanical means," for example by backhoe and crane, Rheinhart said. "But we're looking into the possibility of small, controlled explosives." That process would take about two years, winding up late in 2006.
Funds flowing
This timetable assumes that all the federal money needed for the work will be available. In 1999, Congress authorized $10 million for the project under the Water Resources Development Act.
About $5 million has been appropriated to date. Sen. John Warner and Rep. Jo Ann Davis, R-1st District, have pushed for that funding. The latest $2.5 million chunk of the money was included last month in the Omnibus Appropriations Bill.
Another $2.5 million a year is expected to be requested over the next two years.
Rheinhart emphasized that some of the details of the project could change because they are still in the planning stage.
For example, "We are just beginning to design the removal portion" of the job.
Dismantling the Embrey Dam has been a topic of discussion here for more than a decade. The dam has long since outlived its purpose--to generate electricity--and is considered a safety hazard. In 1987, a child died after falling off the structure.
What's noteworthy about the project is that regulators, environmentalists and local officials, who normally can't agree on much of anything, support it.
"This is the biggest and best thing to happen to the river in two centuries," said John Tippett, executive director of Friends of the Rappahannock. "We're looking in the order of 700 miles of upstream habitat restored" on the river and its tributaries.
The Fredericksburg-based river group initially had some concerns.
"We were working with the corps on areas like removal of the [dam] debris," Tippett said. The concrete will be hauled to landfills for disposal. And FOR wanted to ensure proper handling of the dredged material.
What's happening here is part of a nationwide movement to remove old dams to revive struggling fisheries.
For example, in 1999 the 162-year-old Edwards dam across Maine's Kennebec River was removed, allowing the passage of sea-run fish. The event was long awaited by conservationists and anglers.
The Washington-based American Rivers conservation group has monitored the project and says the Kennebec is showing signs of renewal.
"We very quickly began to see striped bass and sturgeon above the former dam site," said Serena McClain, who works for AR's Rivers Unplugged campaign.
There are approximately 75,000 dams in the U.S. According to McClain, 37 were removed last year; another 70 or so removal projects are in the works.
Pennsylvania and Maine have been leaders in the effort, but other states have been following suit, including North Carolina, California, Ohio and Oregon.
Embrey Dam timeline:
1854--Wood-and-stone crib dam is completed by Fredericksburg Water Power Co. Stone lock on southern end controls water flow into city canal and allows passage for occasional canal boat.
1910--Fredericksburg Water Power Co. finishes construction of new concrete dam to generate electricity. The 770-foot-long, 22-foot-high structure, named after power-company official Alvin T. Embrey, spans the Rappahannock River about 2.4 miles upstream from Fredericksburg's downtown.
1910--Frank Gould buys Fredericksburg Water Co. and establishes Spotsylvania Power Co. Electricity is produced at a powerhouse where the canal reenters the river.
1926--Virginia Electric and Power Co. acquires power plant and dam, operates power plant until shutting it down in early 1960s.
1968--City acquires the dam from Virginia Electric and Power Co.
1980-1990--City studies various plans for new electric-generating plant at Embrey Dam. Plans go nowhere.
1998--Virginia Department of Game and Inland Fisheries study recommends dam removal to aid passage of migrating fish. U.S. Army Corps of Engineers recommendation says fish passage and restoration of Rappahannock River are in public interest, opening up the project to federal funding.
1999--Water Resources Development Act authorizes $10 million for removal of dam.
2000--Corps of Engineers completes feasibility study for dam removal.
2001--Corps receives $500,000 in federal funds for planning, engineering and design to remove dam.
2002--Corps permits issued for removal project.
February 2003--Fredericksburg agrees to purchase 48 acres of land from the Silver Cos. on which to place dredged silt.
March 2003--Bids received for removal of 250,000 cubic yards of sediment behind dam.
February 2004--Dredging to be completed, demolition of 200-foot section of dam to take place. Historical survey of crib dam to begin.
December 2006--Demolition and removal of concrete from Embrey Dam and of crib dam expected to be completed.
Source: Historic Resources Along the Rappahannock and Rapidan Rivers; U.S. Army Corps of Engineers.
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