Removal of a breached orphan dam began Monday that will leave the Conewango Creek completely free-flowing from New York State to the confluence with the Allegheny River.

The Hospital Dam in the creek near Warren State Hospital has been creating dangerous currents for kayakers and canoers. It is being removed by American Rivers in partnership with the Conewango Creek Watershed Association, the state Department of Environmental Protection, the U.S. Fish and Wildlife Service and the Ohio River Basin Fish Habitat Partnership.

Bearan Environmental Services from Butler County is removing the dam with an excavator.

“There was a remnant of a dam upstream from the Hospital Dam, we took that out yesterday (Monday). Both the dams are rock-filled timber crib dams, which means you make a lattice, almost like a log cabin with the logs and then you put rocks inside for stability,” Lisa Hollingsworth-Segedy, associate director of American Rivers Restoration Program, said on Tuesday. “…we pulled out the timbers and then redistributed the rock, so the rock is staying in the stream as part of the stream bed.”

The same process is being repeated for the Hospital Dam, which also has a concrete cap that has to be removed.

The timber in the creek is probably 200 years old, Hollingsworth-Segedy estimated, and has been preserved by the water. Local woodworkers are set to take the logs after they have been removed.

“So rather than throwing it away…it’s going to become furniture or other works of art,” she said. “Because it’s been totally submerged its perfectly preserved.”

The removal of the dam builds on the earlier removal of the Carter Dam near the confluence of the Conewango Creek and the Allegheny River in 2009.

“Removing that dam was important, but it didn’t do all the work the Conewango Creek needed,” Hollingsworth-Segedy said, “since these two structures were still in place. So now with these structures gone the Conewango Creek is going to be completely free flowing from the headwaters in New York all the way to the intersection of the Allegheny River.”

The project should be complete next week in time for the Allegheny River Clean-up, but Hollingsworth-Segedy said they have already removed a number of shopping carts and other items during the project. When the dam removal is complete they re-grade and re-seed any surfaces they’ve disturbed, she said.

“As we’re finding things in the river we’re pulling them out, so we’re kind of doing a little advance clean-up work to help out,” she said.