Riparian Wetland Restoration

Quakertown Preserve

Quakertown Preserve Wetland RestorationThe Quakertown Preserve is an undeveloped 28-acre, wooded property adjacent to working farms in Franklin Township, New Jersey. The property is important for watershed protection as it contains a spring that feeds this first order tributary of Capoolong Creek (aka Cakepoulin Creek), a designated C-1 stream, as well as a mix of cedar and hardwood forest. The Hunterdon Land Trust (HLT) had acquired full ownership of the property with funding from the New Jersey Green Acres Program.

The project sought to restore 2.35 acres of floodplain wetland, wetland transition area and riparian area adjacent to the tributary of Capoolong Creek. The floodplain wetland was previously occupied by an offline, spring-fed, manmade pond created by an earthen berm encompassing approximately a quarter acre or 10% of the project site. The berm was approximately 5 feet high and 300 feet long, disconnecting nearly one third of an acre of floodplain wetland from the adjacent channel, resulting in a net loss of flood storage that has ultimately increased flooding risks up and downstream of the pond. The pre‐development 100 year storm did not overtop the dam while the post restoration floodplain floods during one year rainfall events. Restoring the connectively of streams to their floodplains is an important element of watershed based stormwater management as it serves to maintain the stability of stream channels as well as the water quality.

The project removed most of the earthen berm to restore the impoundment area to the riparian wetland; re-connected the floodplain to the stream in order to increase volume storage during storm events and reduce erosive forces in the downstream reaches; enhance the nutrient removal capacity of the floodplain wetlands; removed invasive plant species proximate to the site; and converted lawn area to woodland. To establish a complex wetland system, the wetland area was unevenly graded to create hummock-hollow micro-topography and planted with a variety of native plants species. Completed in mid-May, 2011, the restored spring fed wetland was dominated by a variety of desirable native plant species including several from the site’s own seed bank by mid-July.

The project was funded through a grant from the New Jersey Wetlands Mitigation Council and the Natural Resources Conservation Service (NRCS) through a Wildlife Habitat Incentive Program (WHIP) Grant. The funding through the wetland mitigation council was the first time the council funded a project that assisted in the removal of a dam and the restoration of an impoundment. This serves as a valuable precedent for other small dam owners and land trusts to remove small impoundments and restore the historic ecological functions of floodplains and riparian zones.