And the devastation it caused can be traced in part to global warming. Hurricane Sandy took the lives of over 100 people in the United States and caused around 50 billion dollars in damages. As Paul Greenberg, author of American Catch, explains that “nothing acquaints you with your city’s topography like living it in the eye of a hurricane and feeling that water flow up and rise up and start to swallow the city.” Flooded Avenue C in the East Village, image by David Shankbone (CC BY 3.0) As the waters rose, the distinction between low and high ground suddenly became very apparent. Seawater poured into the streets, flooding out apartment buildings and filling the subway tunnels. Carey Tunnel during Hurricane Sandy, image by Jay Fine (CC BY 2.0) The storm surge inundated neighborhoods throughout the city. When Hurricane Sandy hit in 2012, New Yorkers were forced to confront their proximity to the ocean. South Manhattan, image by Townie (CC BY-SA 2.0) But just a few blocks away, there are docks, and sea gulls, and ferry boats ready to take you island hopping. They can be shore attached to help maintain the integrity of the shore protection system while seeking to minimize disruption to the alongshore sediment transport system and downdrift erosion.Standing on the sidewalk in Manhattan’s financial district in the shadows of glass skyscrapers, it is easy to forget how close you are to the water. They can attach to an adjacent structure such as a revetment or groin to prevent flanking. Transition structures can vary greatly depending on site-specific conditions of the reach. In order to minimize impacts of structures on adjacent properties, spurs are used as a transitional structure. See Hardaway and Byrne (1999) for more information. These systems require a trained designer and contractor because of potential downdrift impacts. These systems create a natural buffer and preserve and/or create habitat for benthic, estuarine, shallow water, and intertidal organisms. Larger dimensions generally correspond to bigger fetches and where a beach and dune shoreline is desired. For breakwaters, the level of protection changes with the system dimensions. ![]() This method is effective along stretches of shoreline, particularly undeveloped farmland, where more closely spaced headland breakwaters would not be cost effective.Īlthough single breakwaters can be used, two or more are recommended to address several hundred feet of coast. Headland Control is a method of shore control where breakwater units are placed strategically along a shoreline with the understanding that the land between the structures will erode to a predicted stable bay-shape over time. The wide beaches provide most of the protection, so beach nourishment should be included as part of the strategy and periodic beach re-nourishment may be needed. Detached breakwaters are placed farther offshore to allow sand to continue to be transported alongshore. Headland breakwaters maintain stable pocket beaches between the structures and a sand tombolo that attaches the structure to the shore. Breakwatersīreakwaters are a series of large rock structures placed strategically offshore. See Hardaway and Byrne (1999) for more information. These sites may require ongoing maintenance, particularly after storm events. Design and construction generally requires a trained contractor. For long sites, gaps or windows can be placed in the sill to provide access for animals and human recreation. However, the design can be adjusted to fit particular sites. The elevation of the intersection of the fill at the bank and tide range will determine, in part, the dimensions of the sill system. The sand for the wetlands substrate is usually placed on a 10:1 slope from the base of the bank to the back of the sill. ![]() The use of rocks in creating the sill is necessary to protect the created habitat from erosion. Sills create a natural buffer and preserve and/or create habitat for benthic, estuarine, shallow water, and intertidal organisms. It has been used extensively in Chesapeake Bay due to the fact that these structures can be used in a wide range of habitats and energy levels. SillsĪ sill is a rock structure placed parallel to the shore so that a marsh can be planted behind it. Structural living shorelines consist of sills, breakwaters, and transition structures called spurs. Photo - of - Hide Caption In order to maintain a more natural coastal profile, the Shoreline Studies Program at the Virginia Insitute of Marine Science prefers to use Living Shoreline methods for shore stabilization.
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