The grain size of the natural sediment composing the major New Hampshire beaches under summer equilibrium conditions was determined as a first step in assessing the optimal sediment size that would be needed for beach nourishment. In summer, 2015, seven major beaches including Wallis Sands, Foss Beach, Jenness Beach, North Hampton Beach, North Beach, Hampton Beach, and Seabrook Beach were sampled along three to five transects extending from the dunes or engineering structures (e.g., seawalls) to the low water line. In addition, the beach cross-section was profiled using a rover GPS system or the Emery method (profile rods and the horizon). Results indicate that during the low energy conditions of summer 2015, many of the sandy beaches appeared to vary between fine to medium sands with granular sediments and scattered pebbles. Two of the beaches (North Hampton and Seabrook) were somewhat coarser with medium to coarse sands with granular material and scattered pebbles. However, the gravel fractions tended to be under-sampled due to the methodology used. Also, higher energy conditions were not sampled. Therefore, additional studies are needed to fully understand the seasonal changes or changes related to calm (low energy) versus stormy (high energy) conditions in sediment size and characteristics and verification of results presented here.
Center for Coastal and Ocean Mapping
Digital Object Identifier (DOI)
Grant/Award Number and Agency
Bureau of Ocean Energy Management Award Number M14AC00010; National Oceanic and Atmospheric Administration Joint Hydrographic Center Award Number NA10NOS4000073
Ward, L.G., McPherran, K.A., McAvoy, Z.S., and Vallee-Anziani, M., 2016, New Hampshire Beaches: Sediment Characterization: BOEM/New Hampshire Cooperative Agreement (Contract M14ACOOO10) Technical Report, Department of Interior, Bureau of Ocean Energy Management, Marine Minerals Division, 45600 Woodland Road, Sterling, VA, 20166, 37 pp. https://dx.doi.org/10.34051/p/2021.29