Erosion and Accretion Trends of New Hampshire Beaches from December 2016 to March 2020: Results of the Volunteer Beach Profile Monitoring Program

TitleErosion and Accretion Trends of New Hampshire Beaches from December 2016 to March 2020: Results of the Volunteer Beach Profile Monitoring Program
Publication TypeReport
Year2021
AuthorsWard, LG, Morrison, RJ, Eberhardt, AL, Costello, WJ, McAvoy, ZS, Mandeville, CP
Number of Pages420
Organization NameNew Hampshire Sea Grant and University of New Hampshire Extension
LocationDurham, NH

New Hampshire Atlantic beaches were monitored from December 2016 to March 2020 to determine seasonal changes in morphology and elevation, assess the response of the beaches to storms with respect to erosion and subsequent recovery, and develop a baseline to determine long-term trends in beach size, elevation, and position. A unique aspect of this study was the involvement of community volunteers working together with the University of New Hampshire (UNH) Center for Coastal and Ocean Mapping, UNH Cooperative Extension, New Hampshire Sea Grant, and the New Hampshire Geological Survey. The monitoring network consisted of thirteen stations located at six of the major beaches, including each of the state beaches. Monitoring stations were located at Wallis Sands, Jenness Beach, North Hampton Beach, North Beach, Hampton Beach, and Seabrook Beach. At least two stations were located at each beach (Seabrook Beach had three stations). Beach elevation profiles were run routinely at each station at approximately three- to four-week intervals. Additional measurements were made following several major storms. In total, approximately 400 elevation profiles were run at the thirteen stations. The elevation profiles were run using the Emery (1961) method which utilizes two calibrated rods and the horizon for leveling. Sediment volume calculations were made for each profile that approximated the amount of material in the intertidal zone for that profile at that point in time for a one-meter wide swath of the beach. Seasonal changes and storm impacts on beach elevations, profile characteristics, and sediment volumes are discussed in detail for each beach and the major conditions and processes that control their stability discussed.

DOI10.34051/p/2021.34