Garden State Parkway Gunning River Freshwater Wetland Mitigation

Evergreen Environmental, LLC retained Princeton Hydro, LLC to provide scientific, engineering, permitting, herbicide treatment, and construction oversight support to deliver compensatory wetland mitigation credits required for the expansion of the Garden State Parkway in southern New Jersey.

Princeton Hydro was responsible for completing hydrologic assessments, conducting wetland delineations and habitat surveys, coordinating regulatory agency involvement for sensitive species occurrence, developing wetland mitigation concept designs, obtaining permits for final design plans, issuing contractor bid specifications, and overseeing project implementation. The project also required regular interactions with members of the New Jersey Wetland Mitigation Unit of the NJDEP.

To compensate for wetland disturbances associated with widening of the Garden State Parkway, Princeton Hydro developed a mitigation plan for an 8.4-acre former Christmas tree farm. The mitigation design included a hydrologic study, a water budget, wetland delineation, a swamp pink survey, and a flood hazard permit. The mitigation design included elements of wetland preservation, enhancement, creation, and restoration. After the first growing season, the mitigation site possessed 92% cover and 97% survivorship of woody plant material. The site also possessed a vernal habitat component that supported several frog species.

Upon completion, the mitigation site was conveyed to U. S. Fish and Wildlife Service to become part of the Edwin B. Forsythe National Wildlife Refuge.