Coastal, River, & Wetland Restoration
- Shoreline Stabilization Pope John
Paul II Park
Neponset River, Massachusetts
the challenge The Massachusetts Department of Conservation and Recreation (DCR) planned to create a new 72-acre park at the mouth of the Neponset River on a former landfill site, establishing a major urban park as the cornerstone of the river and waterfront greenway system connecting greater Boston with the Neponset River Estuary. The Bioengineering Group was retained as a consultant to advise the park design team through study of shoreline and vegetation processes and to develop a shoreline stabilization plan for the banks of the park along a tidal portion of the Neponset River.
the interdisciplinary approach Bioengineering Group staff first conducted a site assessment to determine the root causes of the erosion and to gain an understanding of site hydraulics and hydrology. Three alternatives were identified and cost estimates were prepared. After review, one alternative was selected that recommended the installation of bank stabilization treatments at the marsh/mudflat interface, plus pulling the fill back 20 feet to create a supplemental marsh zone for enhanced attenuation of contaminants and to serve as a physical buffer between the landfill toe and the actively migrating river channel. This approach also restored habitat and provided the most desired aesthetics for the park setting.
Working closely with the prime contractor, we then developed a detailed set of construction specifications, including a materials and labor cost estimate. The construction specifications provided site prep, marsh restoration planting, and stabilization structure installment guidelines. Other project deliverables included assessment of coastal river erosion and development of preliminary bank stabilization designs, meadow establishment and stormwater management strategies, plans for wetland restoration, erosion and sedimentation control plans, and construction sequencing recommendations.
the results Today, Pope John Paul II Park re-connects area residents to the resources of their unique and delicate river estuary by offering picnic facilities, soccer fields, play areas, paths for walking, restored salt marsh, and extensive plantings of native trees and shrubs. Restoration of this formerly degraded, contaminated, and stigmatized site has also benefited coastal wildlife and habitat with black ducks, mergansers, teal, Snowy Egrets, and Great Blue Herons now often seen in the newly expanded salt marsh, that together with the bank stabilization treatments, has effectively stopped the erosion that threatened the landfill cap. The park and its waterfront trail along the restored coastal saltmarsh enjoy heavy use by a diverse and appreciative community from within Boston as well as the surrounding region.