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Hand-hewn yellow pine timbers from a crib dam built in 1855 sit atop the Embrey Dam, which will be demolished to allow the Rappahannock to flow freely again.
First Lt. Chris Hurst, executive officer for the Army Dive Company, follows Sgt. 1st Class Terry Bryant, a master diver, after showing a visitor the area |
Bundled up against the cold and squinting through snow flurries, a group of Fredericksburg officials carefully made their way along the drab concrete catwalk leading to Embrey Dam.
In single file, Mayor Bill Beck, Doug Fawcett, the city's public works director, and his assistant, David King, and half a dozen others braved an icy wind yesterday afternoon for a close look at the dam, which will be breached next month.
It was something of a farewell tour for the dam off Fall Hill Avenue; another group from the city made a similar visit two weeks ago.
"It's kind of a last chance to see it," said Beck, who has paddled on the Rappahannock River near the dam many times, but has rarely seen it up close.
From the catwalk--normally locked behind a rusting steel gate--the imposing 22-foot-high dam looks much higher than it appears from Fall Hill Avenue or Riverside Drive.
Beck was hoping to get into the arched walkway inside and under the dam, but that was not possible for the city group.
Fawcett opened a metal trap door leading to the walkway to explain why.
"There's about 2 feet of ice down there," he said shouting over the roar of the river, which would make walking difficult--and dangerous.
As the group milled around the catwalk along the side of the dam, construction workers using a jackhammer were punching a hole through the concrete deck to the walkway underneath. That will make it easier for a military demolition team to breach a section of the dam on Feb. 23.
The soldiers will be able to pass materials through the hole, rather than through the narrow trap door.
Several members of the Army's 544th Engineer Dive Detachment from Fort Eustis in Hampton Roads were able to check out the innards of the dam yesterday prior to the city tour.
They've been in town several times already to get the information they'll need to properly place more than 600 pounds of plastic explosives.
They'll be back a few days before the breach to make final preparations to remove a 100-foot section of the reinforced concrete structure, starting about 130 feet from the Fredericksburg shore.
If all goes as planned, one of the loudest booms ever heard in Fredericksburg will reduce a portion of Embrey Dam to steel-studded rubble.
After the blast, a 7-foot wall of water will rush downstream, falling gradually as it goes. According to calculations, the crest will be 4.6 feet at the head of Laucks Island, 4 feet by the time it reaches the Falmouth Bridge, and about 3 feet higher than normal downstream at the Ferry Farm-Mayfield Bridge.
Engineers have said that the rising water will not damage any structures.
Under the project headed by the U.S. Army Corps of Engineers, a contractor has removed about 250,000 cubic yards of sediment that had collected behind the dam. That was dredged and pumped into a pit above the river on the Fredericksburg shore.
The company, Woodside Construction of Dayton, Md., also removed part of a historic wooden crib dam about 25 feet upstream of Embrey Dam. Dozens of large yellow pine beams from that structure are stacked in a pile along the shore. Some of them have already washed downstream, lodging on a small island about 50 feet from the dam.
Archaeologists will study the remaining portions of the 1855 crib dam this summer.
Embrey Dam was built in 1910 to generate electrical power. Now obsolete, it is a liability to the city and an obstacle to migrating fish.
The $10 million removal project is expected to be completed in 2006.
To reach RUSTY DENNEN: 540/374-5431 rdennen@freelancestar.com
