Thursday, December 15, 2016

New culvert on Pa.'s Little Lyman Run opens up nearly 8 stream miles

By Amy Wolfe

In terms of fish passage, a certain culvert on Pennsylvania’s Little Lyman Run in Potter County was about a bad as it gets.

Only 1.9 percent of predicted flows would allow adult brook trout to make it through the culvert on the small tributary to Cross Fork Creek, according to a TU aquatic organism passage inventory.

That number is now 100 percent, thanks to a culvert replacement project completed this summer.

Replacing the undersized culvert not only opens up 7.8 stream miles of coldwater trout habitat, it also will result in reducing 3.6 tons of annual nonpoint sediment inputs. Managing erosion from undersized or failing culverts is often burdensome for local townships.

Construction began on Aug. 3 and was finished on Sept. 11.

Among the groups that made the project possible were the National Fish and Wildlife Foundation, Pennsylvania Fish and Boat Commission, Orvis, Kettle Creek Watershed Association, and Abbott Township. and numerous other agencies and stakeholders. TU biologists collected fish data, using electrofishing and fish tagging methods, prior to the culvert replacement and will evaluate the project’s success by monitoring fish passage through the new culvert in coming months.

Below is a step-by-step look at the project.

Notice the age of the original structure and the failing wingwall on the right hand side. In addition to the benefit to aquatic organism passage, those are two additional reasons the culvert was due for replacement.


A bypass pipe carried the flow of water during the construction during excavation of the area for the footers.


A form is in place for a footer upon which the structure will be placed.



The footers use rebar added for strength.

Concrete is poured into the footer upon which the arch will be assembled.



Footers for both the arch structure and wingwalls, just after the concrete has been poured.


The first sections of the aluminum arch have been put into place.

The arch assembly has been completed. Note the size difference between the old pipe and the new arched bottomless arch opening.


Headwalls poured and forms removed, the structure is nearing completion.

Amy Wolfe is Trout Unlimited’s Eastern Brook Trout Habitat Initiative Director and also oversees TU's Abandoned Mine Drainage work. She is based in Lock Haven, Pa.