Fish making the spring spawning run from the Chesapeake Bay upstream into the Patapsco River swim about 11 miles of cool, shallow, flowing water before hitting a concrete wall nearly three stories high: the Bloede Dam. The wildlife obstacle and human safety hazard has stood for more than a century in Patapsco Valley State Park, but its days could be numbered.
The Maryland Department of Natural Resources is continuing a years-long effort to clear the Patapsco of dams that have outlived their original industrial uses and now turns its attention to Bloede. The dam is the largest of the Patapsco dams, and the most significant in terms of both wildlife and historical value.
"This one is the most important," said Jim Thompson, a DNR fisheries biologist, of the dam that straddles the Baltimore and Howard County line, 230 feet across and nearly 30 feet tall along the spillway. Because the Bloede Dam is the first obstacle that herring, shad and American eels hit as they head upriver, wildlife would benefit greatly if it were removed, he said.
"In my mind, it's huge," Thompson said of the potential impact of removing the dam, which is owned by the Department of Natural Resources. While there is a fish ladder next to the dam — a concrete, zig-zagging affair on the Howard County side — it's at best an imperfect solution. Studies have shown that relatively few fish make it up the ladder, installed in the early 1990s and the longest in Maryland at 316 feet.
Charles Wagandt, a vice president of Patapsco Valley Heritage, a group devoted to preserving the area's natural and historical features, called the Bloede "one of the most significant historical sites in the valley." The group has not yet taken a position on removing the dam, Wagandt said.
As the DNR begins deliberations about the dam, state officials are accepting public comments through its website, dnr.state.md.us, and at open houses scheduled at the Catonsville Public Library from 2 p.m. to 8 p.m. Thursday and from 9 a.m. to 4 p.m. Friday.
The state and its partners in the project — including the environmental organization American Rivers and the National Oceanic and Atmospheric Administration — are considering four alternatives, two of which involve removing the dam.
Removing it is "the preferred option, but not the guaranteed option," said Gina Hunt, the DNR's deputy fisheries director. She emphasized that the agency is just beginning to analyze options, and there are complications — including environmental review and engineering details — that could stand in the way.
Since 2010, two dams upriver have been removed: first the Union, then Simkins, with a total cost in state and federal funds of about $2.7 million, Thompson said. That leaves the Daniels, the farthest upriver, and the Bloede, the largest of the four. The Bloede Dam would likely cost $1.5 million to $2 million to remove, Thompson said.
Hunt and Thompson said removal is the preferred option because it best fulfills the chief goals of the project: to increase the fish and eel populations and eliminate a human safety hazard. Thompson said four or five people have died at the dam in the past 20 years or so.
The rushing waters, wooded setting and historical interest make the Bloede Dam a magnet for park visitors, but not all heed the warning signs posted in English and Spanish: "Danger ... Area closed to public use ... Drownings have occurred."
People walk across the dam or make a game of sliding off into the river below, where they can get caught in the churning waters.
"People who don't realize the danger or don't care," said Serena McClain, American Rivers' director of river restoration.
She spoke above the roaring water on the Howard County side, where the fish ladder runs along the river, then turns inland, up the bank and over to the upstream side of the Bloede. It's an impressive-looking concrete structure, but it does a poor job of conveying fish and eels across the dam, she said.
"There's no way, with all that water flowing over the dam, a fish is going to find that entrance" to the fish ladder, McClain said. Water stretches about 160 feet across the spillway, and the fish ladder entrance is only a few feet wide.
A consultant's report prepared for American Rivers and released last week said up to 90 blueback herring and hickory shad were found in 15 minutes of sampling just below the dam in the spring of 2011. Above the dam, "none of these migratory species have yet been collected," the reports said,
American Rivers is devoted to restoring waterways across the country. McClain points to success stories in Maine, where she said dam removals in the past decade have helped to restore the herring population in the Kennebec River and bring back a commercial fishery.
She said environmentalists will likely support removing the Bloede, as will canoeists, kayakers and tube riders who would benefit from the improved passage down the Patapsco. She said some opposition could come from people who want to preserve the dam for its historical value and those who like the familiar scene.
"Our biggest challenge with the public is going to be, 'It's always been here,'" she said.
The dam was built in 1906 to generate electricity for Victor G. Bloede's Patapsco Electric and Manufacturing Co., according to a historical documentation prepared by a consultant last year for the Maryland Historical Trust. It provided electricity for a 57-lot community called Eden Terrace being developed by Bloede, a German immigrant who moved to Baltimore in 1877 to establish a textile company.
According to accounts of the time, the power plant was inside the dam and underwater. It has not generated electricity since 1932, and the equipment has been removed, according to the report prepared for the Maryland Historical Trust.
"It was the world's first hydroelectric plant underwater," said Wagandt. For that reason, he said the dam's historical value surpasses the Union, Simkins or Daniels dams.
Wagandt said the group did not oppose the removals of the Union or Simkins dams. Bloede is not on the National Register of Historic Places, although a consultant hired by DNR concluded in a report to the Maryland Historical Trust last year that the dam is eligible for listing. Union dam was included as part of the Oella Historic District under the National Register of Historic Places, but was not separately listed.
National Historic Register listing does not protect a structure from demolition, but McClain said it means something would have to be done to offset the impact of removing it. McClain said that could mean leaving part of the original structure intact, and posting information and photographs illustrating the site's historical significance.