Jim Thorne Memorial Bridge

November 22, 2022

By Daniel Barringer, Preserve Manager.

Dr. Jim Thorne posing with a mountain behind him

Photo courtesy Rosemary FitzGerald Thorne

We recently dedicated a new footbridge at Crow’s Nest in memory of Jim Thorne who was our Conservation Scientist at Natural Lands. Among his other achievements he pioneered prescribed grazing for rare species habitat management at Crow’s Nest, helped develop our prescribed fire program and helped establish the Pennsylvania Prescribed Fire Council, conducted research on oak regeneration here, and founded the Hopewell Big Woods, a cooperative effort to protect, manage, and promote the largest forested area in southeastern Pennsylvania. You can read more about Jim’s work here. Above, Jim poses with a typical relaxed grin in the wilderness he loved.

I’ve held off writing about the footbridge we built here at Crow’s Nest in Jim Thorne’s memory until it was finished and dedicated. The bridge was gifted by Jim’s spouse Rosemary FitzGerald Thorne and their kids Megan, Dylan, and Matt and their families. I’m pleased to share the story of the build with you and to have had the privilege of working on this project.

Man taking measurements for a concrete foundation for a footbridge

Photo: Daniel Barringer

This project build would not have been successful without the commitment and skill of Jim Moffett, Force of Nature volunteer and new Preserve Manager for the nearby French & Pickering Creeks Conservation Trust. He took on this project even as he was starting a new job and moving to live on the preserve he now manages.

The restored site of a natural-flowing stream where there had been a pond with a failed dam proved to be the perfect location for a footbridge. But before we could pour the concrete foundations we had to dig four holes. Jim Moffett measured the precise location and then staff and interns dug the holes. Let me tell you, they were the most difficult holes we’ve ever dug! Cody Hudgens (below) and interns Allie Cook and Joe Tricarico all took turns digging, prying, and operating the jackhammer to get the holes opened up.

Man using a jackhammer to prepare a footbridge foundation

Photo: Daniel Barringer

Jim Moffett created the three pairs of beams cut on an arch with an 85′ radius, laid out in our driveway. We cast the brackets in the wet concrete and later carried the beams down to the stream. Below, he attaches a bracket that carries the weight of the middle beam. Jim and I worked on the project mostly in the evenings after work and we enjoyed some beautiful weather and sunsets.

Man preparing joists for arched footbridge installation

Photo: Daniel Barringer

Then the handrail posts went up and I seeded grass on the newly-graded path.

Partially completed arched footbridge

Photo: Daniel Barringer

Below, Jim Moffett scribes the decking around the handrail posts.

Man marking boards for footbridge

Photo: Daniel Barringer

Finally, the handrails were ready to be installed. The side rails are also cut on a radius with the top of the handrail simply bent into a curve.

Nearly completed arched footbridge

Photo: Daniel Barringer

We had a plaque made to honor Jim Thorne. We feel fortunate to have known him and benefitted from his research—the applied variety that has real-world outcomes.

Memorial plaque for Jim Thorne

Photo: Daniel Barringer

Jim Thorne’s family poses on the footbridge during the dedication. We are grateful for their generosity since they shared Jim with us and also made the footbridge possible.

Families gathered on arched footbridge

Photo: Daniel Barringer

You can see the footbridge crossing the stream in the restored landscape of wildflowers and wetland shrubs.  Below is the view from Piersol Road, intended to entice visitors to explore the trail system. You can cross the stream on the new footbridge if you continue upstream from our tiny library (that is, not cross the bridge next to the tiny library—you can return that way if you like). Leave the yellow-arrow Creek Trail and follow the gray trail arrows up toward the maintenance barn (the driveway here is part of the trail system). Cross the open field to the left past our rain garden and continue following the gray arrows into the restoration area. There’s a bench at the top of the hill above the bridge to provide rest, then the trail continues up to the Chief’s Grove and reunites with the yellow-arrow trails.

Arched footbridge across stream in valley

Photo: Daniel Barringer

Thank you to all who made this project possible. We hope you enjoy the experience of crossing the bridge as much as we did building it!