Marsh Creek Stabilization

After a decade of planning, initially to mitigate community flooding along a low-set railroad line, the commissioners of Tioga County have greatly improved a mile-long stretch of Marsh Creek in the rural Pennsylvania community of Stocksdale. With the growing popularity of hiking trails in Pennsylvania, the commissioners also drove a vision to create a new, adjacent trail to boost community recreation, relocate a portion of the creek to achieve a more stable channel and enhance conditions for fish habitats.

This complex project involved placement of more than 700 tons of rock ballast at the base of the rail line as protection from washout and flooding.  A full width hiking trail base was built next to the rail line in anticipation of a future trail to more completely connect Jersey Shore to Wellsboro to Tioga Junction, a distance of about 65 miles. The installation of rock ballast undergirding the rail line was made more difficult because the railroad was in active operation.

The project was financed through a grant from the Pennsylvania Department of Environmental Protection’s Growing Greener, a fund which represents largest single investment of state funds in Pennsylvania’s history which helps to support watershed restoration and protection.

Larson Design Group provided the county with design and construction inspection services. This included extensive DEP permitting which was challenging because LDG had to complete the hydraulic studies for the project sites and then add the stream enhancement structures on the back side of the application process. The structures were changed from rock to timber to save costs.

LDG’s design reduced streambank erosion caused by a U-shaped (oxbow) curve in the creek. The solution was a network of cross-vane deflectors, log vanes and mud sill cribbing to control the hydraulics and stabilize the channel.

One of the most challenging aspects of the design was submitting a joint powers agreement application for grant funding. The JPA was a binding agreement between public agencies U.S. Army Corps of Engineers, the Pennsylvania Department of Environmental Protection and the County of Tioga, which share a common power and jointly are pursuing community enhancement programs. Among other agencies, the Corps of Engineers had a role in requiring compliance with requirements for the new fish habitat.

Another challenge was managing a construction schedule to include many independently moving parts, ranging from permitting and construction deadlines to railroad schedules, rock delivery, tree removal and replanting. Keeping track of the quantities of rock used was needed for government record-keeping and future audit requirements.

LDG’s experience helped the project be completed ahead of time and under budget, and the hiking trail is under design.

Facts and Figures:

Proposed Stream Width = 16.2’ to 38’

LDG Construction Cost Estimate = $750,000.00

Bid Spread = $479,142.00 to $920,515.50

As-Built Cost = $636,653.08