C+S April 2023 Vol. 9 Issue 4

sion over the dune near a vehicle overpass, which was rectified within hours! The Village of West Hampton Dunes was up and running within 24 hours of Sandy’s visit.” Terchunian has worked with the Army Corps for decades as a representative of several south shore villages and towns on the east end of Long Island. Storms, like Sandy, may occur more frequently in the future due to relative sea level change. The project is monitoring relative sea level change and adjusting the project when necessary, so that it will con- tinue to perform as planned. This may mean over time increasing the volume of sand that is placed on beaches and increasing the height of dunes to account for observed increases in relative sea level change. Joseph Vietri, Director of Coastal Storm Risk Management National Center of Expertise, North Atlantic Division, U.S. Army Corps of En- gineers, who happens to live on one of the barrier islands said, “It’s predicted that future low, intermediate, and high rates of Army Corps relative sea level change projections could increase anywhere between approximately one to six feet over the next 100 years, resulting in more frequent and severe storm damages.” According to Bridges, natural and nature-based features may actually be more capable of adapting to changing environmental conditions than conventional features. He said, “For example, if you have a levee and marsh as part of a project. The hard levee will not move in response sea level rise, but the marsh can migrate on its own if we haven’t put something in its way.” Hudson Raritan Estuary New York and New Jersey Ecosys- tem Restoration Project The Hudson Raritan Estuary is located within the boundaries of the Port District of New York and New Jersey and is situated within a 25-mile radius of the Statue of Liberty National Monument. An estuary is a partially enclosed, coastal water body where freshwater from rivers and streams mixes with salt water from the ocean. Estuaries can include a variety of habitats including salt marshes, mangrove or mari- time forests, mud flats, tidal streams, rocky intertidal shores, reefs, and bar - rier beaches. The Hudson Raritan Estuary is a complex ecological system located within a highly urbanized region of 20 million people that includes the New York Harbor, rivers, wetlands, coastlines, and open waters. Over the years, industrialization has degraded the estuary and hardened the coastlines resulting in the tremendous loss of habitat. The estuary has lost more than 85% of its tidal wetlands, 99% of its freshwater wetlands, and 100% of its oyster reefs. Restoring the estuary is important because the ecosystem provides habi- tat for birds, fish, shellfish, and other wildlife, maintains water quality by filtering out contaminated sediments, provides recreational opportuni - ties, boosts the region’s economy, and acts as a buffer from flooding for coastal communities during destructive and powerful storms. One study done by Lloyd’s of London showed marshes play a criti- cal role in reducing damage to infrastructure from coastal storms. The study showed that during Hurricane Sandy marshes prevented $625

million in direct flood damages across twelve states. In New Jersey, coastal marshes reduced property damages by more than 20 percent. Lisa Baron, project manager, New York District, U.S. Army Corps of Engineers said, “The plan for the Hudson Estuary Program is to restore a mosaic of 621 acres of habitat at 20 individual project sites. These projects will restore estuarine and freshwater wetlands, shorelines, fish passage, oyster reefs, shallow water habitat, coastal forests and marsh islands while providing maximum ecological and societal benefits to the region.” Work is starting up on several of these restoration sites. Natural and nature-based features being used include salt marshes and oyster reefs. Restoration of Salt Marshes According to the International Guidelines, coastal wetlands and inter- tidal areas can reduce flood and erosion risks in coastal environments because they can dampen wave, surge, and current energy, trap sedi- ments, and, in the correct settings, be self-sustaining under rising sea levels and other pressures. They provide additional benefits including fish production, filtration of pollutants from upland runoff, water qual - ity mediation, recreation, and carbon sequestration. Within the Hudson Raritan Estuary is Jamaica Bay. The bay is located in portions of the Boroughs of Brooklyn and Queens in New York City and is part of the Jamaica Bay Park and Wildlife Refuge, the country’s first national urban park and one of the Gateway National Recreation Areas that is visited by millions of people each year. The bay covers 26 square miles and opens to the Atlantic Ocean. The land surrounding the bay is heavily developed and includes John F. Kennedy International Airport, the Belt Parkway, and several landfills. Inside the bay there is a marsh island complex. In the last century, these once-vibrant islands have been rapidly disappearing resulting in extensive habitat loss. Eight five percent of the wetlands have been lost in the region. This loss is primarily due to human development that’s included the filling in of marshes and open water areas, hardening of shorelines, sewer overflows, and landfill leachate or water containing contami - nants seeping from landfills. The disappearing marshes pose a threat to wildlife and coastal communi- ties. It’s been estimated that the marsh islands if left alone would vanish completely by 2025. Fortunately, due to work the Army Corps has per- formed over the years, this won’t happen. The Army Corps, along with partnering agencies, has restored approximately 160-acres of marsh is- lands in Jamaica Bay through a number of successful restoration projects. According to Baron, “Restoring these marsh islands provides signifi - cant benefits to the region. The restored marsh islands keep the sedi - ment within the Jamaica Bay system; wetland vegetation stabilizes the island; the islands reduce waves and erosion of surrounding shorelines and adjacent islands; the wetlands improve water quality within the bay; and the marsh islands that we construct will continue to build the ecological resilience of the bay to respond to increasing sea level rise.”

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