Understanding the Role Coastal Marshes Play in Protecting Communities from Storm Surge and Flooding

  • This project focuses on Piermont Marsh, which lies adjacent to the Village of Piermont, 15 miles north of New York City.

    This project focuses on Piermont Marsh, which lies adjacent to the Village of Piermont, 15 miles north of New York City.

  • This project was shaped by experiences during Hurricane Sandy, an extremely destructive hurricane that made landfall in New Jersey in October 2012.

    This project was shaped by experiences during Hurricane Sandy, an extremely destructive hurricane that made landfall in New Jersey in October 2012.

  • Project plans were shaped by many discussions such as this community forum in January 2015.

    Project plans were shaped by many discussions such as this community forum in January 2015.

  • This project used computer models to examine the potential impact of a proposed marsh management plan. Had the plan been adopted, it would have restored native cattails within three areas (outlined in orange) of this Phragmites-dominated marsh over ten years..

    This project used computer models to examine the potential impact of a proposed marsh management plan. Had the plan been adopted, it would have restored native cattails within three areas (outlined in orange) of this Phragmites-dominated marsh over ten years..

  • The team measured local stands of cattails and invasive Phragmites to ensure the team’s model would accurately simulate marsh vegetation. (Credit: C. Angelini)

    The team measured local stands of cattails and invasive Phragmites to ensure the team’s model would accurately simulate marsh vegetation. (Credit: C. Angelini)

  • These model generated images show how wave height gets significantly lower as waves move from the estuary to land. Scenario 4 shows a large storm in 2050 when sea level is projected to be 18 inches higher..

    These model generated images show how wave height gets significantly lower as waves move from the estuary to land. Scenario 4 shows a large storm in 2050 when sea level is projected to be 18 inches higher..

  • Project findings are informing decisions about marsh management and shoreline infrastructure.

    Project findings are informing decisions about marsh management and shoreline infrastructure.

As coastal communities strive to safeguard themselves from increasing storm risks they are looking for ways to maximize the protective powers of their natural features, such as coastal wetlands. This project closely examined one marsh complex that lies adjacent to Piermont Village along the Hudson River Estuary in New York. Village residents wanted to better understand how Piermont Marsh buffers their Village from storm-induced flooding and waves, and whether a proposed plan to restore native cattails within a small area of the phragmites-dominated marsh would lessen its buffering capacity. 

In partnership with the local community, the research team designed and applied computer models to simulate marsh vegetation and storm impacts produced by a series of past and future storm scenarios. They found that both mature stands of cattails and phragmites within Piermont Marsh protected the adjacent Village from waves and damage from floating debris, but the marsh didn’t reduce the level of flooding resulting from severe storms. By looking back at Superstorm Sandy in 2012 and projecting how much worse the damage could have been without the marsh, the research team was able to put a dollar value on Piermont Marsh’s buffering services. Through this project’s collaborative process, marsh managers gained a better understanding of how to sustain the suite of ecosystem services provided by the marsh and Village residents now have new tools for anticipating and managing the impacts associated with intense storms.