Hurricane Sandy: Beach-dune performance at New Jersey Beach Profile Network sites

Abstract

The Coastal Research Center at the Richard Stockton College of New Jersey (CRC) initiated a post-storm survey and assessment of the New Jersey shoreline in re- sponse to Hurricane Sandy which made landfall in Atlantic County on 29 October 2012. The CRC has monitored shoreline trends for 28 years at 105 locations for the state-sponsored New Jersey Beach Profile Network (NJBPN) project and the data provided clear evidence on how the beaches performed during the storm. Ocean waves combined with storm surge caused significant erosion to the beaches and dunes along New Jersey's Atlantic shoreline. Wave and surge elevations increased northward from the area of landfall, which contributed to increased erosion. Mea- surements of wave run-up ranged from 14.5 ft (NAVD88) at Atlantic City in Atlantic County to 24.6 ft (NAVD88) in Long Branch in Monmouth County, which suffered the greatest beach-dune volume losses of the stations within NJBPN. The extent of erosion of the beaches and dunes and damages to structures and infrastructure were dependent upon the elevation of the storm waters, volume and extent of the berm, elevation and width of the dune, and local management practices for shore protection. North of landfall, where storm surge and wave energy (and subsequent beach-dune damages) were greater, federally designed shore protection projects that included engineered dunes protected landward structures, particularly in Long Beach Island (Ocean County) where design dune elevations were 22 ft NAVD88. Communities that suffered the greatest damages to structures and infrastructure were those where dunes were non-existent, or where elevations of the beaches and dunes were low or had narrow beach widths. In addition, setbacks for new structures landward of secondary dunes or adhering to National Flood Insurance Program standards for elevation allowed adjacent structures to be spared damages. ADDITIONAL KEYWORDS: Hur- ricane Sandy, New Jersey Atlantic shoreline, coastal erosion, shoreline change, coastal dunes, beach nourish- ment, overwash, New Jersey Beach Profile Network.