Coastal, River, & Wetland Restoration
- Broad Meadows Marsh Restoration
Quincy, Massachusetts
the challenge At Broad Meadows Marsh in Quincy, MA, approximately 106 acres of tidal salt marsh habitat had been utilized as a dredging spoils disposal area at various times in the past. The Bioengineering Group was retained by the U.S. Army Corps of Engineers to study the feasibility of various alternatives under Section 1135. The intent was to restore marshland in a manner that would improve local recreation resources, withstand storm surge and wave impact, and improve habitat without creating West Nile Virus and related mosquito-borne disease hazards in a dense urban setting.
the interdisciplinary approach The primary goal was to restore Broad Meadows Marsh to an ecologically functioning salt marsh by reestablishing hydrological connections between the marsh and the surrounding river and harbor. We identified and developed a plan for restoration of the marsh and related resources by analyzing hydrological, hydraulic, and geotechnical data and refined it, based upon incremental analysis, for the most beneficial restoration outcome. These determinations took into account a 100-year tidal event coincident with waves from a strong hurricane. This data was incorporated into the overall feasibility plan along with modeling data of the 100-year maximum tide event with evaluation of wave over-topping risk. Also determined was how to best to maintain a diverse wetland habitat, including salt pannes and tidal ponds. The ponds helped mitigate nuisance mosquitoes by providing habitat at low tide for fish that feed upon mosquito larvae.
the results We developed a highly cost-effective solution that removed fill from approximately half the marsh, placed the fill onto remaining filled portions, and contained all fill behind a stable armored berm. The newly created terrain provided playing fields to serve nearby schools, and the berm included an ADA compliant path allowing strolling and bird-watching overlooking adjacent restored wetlands. Mosquito control was obtained through open water marsh management measures proven to deliver optimal results within the region.