Imagine it’s a blistering hot summer day and your house has only one room that’s air-conditioned.
But there’s a problem: The door operates only one way. You can leave the cool room, but you can’t go back in.
That’s what happens when a dam or a perched culvert creates a blockage on a stream, and that’s why Trout Unlimited and its partners put so much effort into addressing such barriers to aquatic organism passage (AOP).
Another barrier down
A barrier on Wolf Den Run in the Potomac Highlands of Maryland––a TU Priority Waters area––was among the many AOP projects TU tackled in 2024.
The failing culvert––just meters from where Wolf Den Run enters the North Branch of the Potomac River near the community of Shallmar––was impassable to upstream fish passage.
“It was a priority project because the culvert was failing and the road offers the only vehicle access to Shallmar,” said Ben Harris, program manager for TU’s Western Maryland Initiative. “The county had an urgent need to replace the stream crossing.”
When TU tackles AOP projects the goal is two-pronged; new construction must not only improve the crossing’s ability to handle high flows while minimizing the risk of road damage; but also, must eliminate the barrier to fish passage.
An added challenge was the need for the project to be completed as quickly as possible.
“The community is probably only 60 or 70 people but it’s the only access, so it had to happen fast,” Harris said. “We needed to have a pre-formed structure rather than pouring concrete and giving it time to cure.”
To ensure access to town remained, the team created a temporary crossing just upstream from the worksite.
Projects are better with partners
A grant from TC Energy helped cover the cost, which Harris said was likely 20 to 30 percent higher because of the need for the pre-formed structure.
TU handled project design while the Garrett County Roads division handled the bulk of manpower.
The U.S. Fish and Wildlife Service, an agency deeply involved in fish passage efforts, was another key partner in the project, which was completed in early October.
Freedom to swim
Fish can now move between the larger North Branch of the Potomac and Wolf Den Run, in which fish can seek thermal refuge during warmer months, as well as habitat for feeding and spawning at other times of the year.
“We did one pretty substantial habitat project up there before my time,” Harris said. “And we actually did another culvert project up there, too, and are eyeing another spot for a project between those sites. “So it’s hotbed of activity for TU and a good place to do work.”