Project Overview

Wetland Mitigation in the Norristown Farm Park

Wetland Mitigation in the Norristown Farm Park

Cross vane installed in Stony Creek

Cross vane installed in Stony Creek

Modified mud sill along the left bank of Stony Creek

Modified mud sill along the left bank of Stony Creek

PTC Wetland Mitigation and Stream Restoration in Norristown Farm Park

The Pennsylvania Turnpike Commission (PTC) has completed compensatory mitigation projects to make up for the loss of an estimated 1,300 feet of perennial streams and just over 2 acres of wetlands that will be permanently impacted by the construction of the Northeastern Extension Total Reconstruction and Widening Project between the Mid-County and Lansdale Interchanges (MP A20-A31). More specifically, two separate projects were developed: one to establish new wetland areas and another to restore a section of Stony Creek. Both projects are located in the Norristown Farm Park in East Norriton Township and Norristown Borough, Montgomery County.

Wetland Mitigation

Working with federal, state and local stakeholder groups, the PTC began planning the wetland mitigation project during the engineering design phase of the 10.5-mile Northeastern Extension total reconstruction and widening project. The various agencies and local stakeholder groups that worked with the PTC include the Farm Park Preservation Association's Norristown Farm Park Advisory Committee, the Stony Creek Anglers Association, Pennsylvania Fish and Boat Commission, Pennsylvania Department of Environmental Protection (PADEP), and the US Army Corps of Engineers (USACE). The PTC also coordinated with the PA Historic and Museum Commission. Approval of the final plans for the wetland mitigation project (and the stream restoration project as well) was successfully secured from the PA Fish and Boat Commission, PADEP and the USACE.

James D. Morrissey, Inc. of Philadelphia was the contractor on the wetland mitigation project which was completed in late summer 2012. There were three separate locations within Norristown Farm Park targeted for this work which resulted in the creation of more than 3.5 acres of new wetland and over 8 acres of riparian buffer along Stony Creek. The PTC also created habitats for the birds and small animals, which included bird boxes, standing snags (embedded tree trunks), and brush piles. The vegetation recently planted at the wetland mitigation site will be monitored by the PTC for continued growth and if necessary, replacement plantings will occur.

Dam Removal and Stream Restoration

This project is the result of a collaborative effort between the PTC, the PA Fish and Boat Commission and American Rivers with input from the Stony Creek Anglers. The removal of the Norristown Farm Park dam in Stony Creek was completed in fall 2011. The dam removal, which was the first phase of this project, restored the creek to a more natural, free-flowing condition. Crews also reestablished the floodplain, stabilized the edge of creek with large rock, and replanted the banks with willow and dogwood stakes.

The second phase of construction was completed in summer 2013 and involved limited channel grading, stream bank stabilization, and habitat improvements. The in-stream habitat improvements included the installation of cross vanes, log deflectors, a mud sill, and scattered boulder placement in the creek bed.

Map of Norristown Farm Park