Impact of sea-level rise on cultural resources in the Delaware Bay region, USA

The Delaware Bay coastal zone includes at least 1580 cultural heritage resource sites; 700 of them could be damaged or lost by the year 2100. Future projections of sea-level rise (SLR) and storm surges identified cultural resources at high risk for inundation by the years 2030, 2050, 2080, and 2100. The projections are aimed to be high-end estimates preparing for long-term planning and "worse-case" scenarios. Sites located along the riverbanks are facing the highest threats from SLR. Coastal sites will be more frequently impacted by storms as surge levels increase with SLR. Storm-surge simulations predicted a non-linear increase in surge levels, reaching greater heights along the New Jersey side of the Bay compared to the Delaware side. Coastal sites without a protective dune system, or a dune less than 2 m in elevation, should be considered at immediate risk from coastal flooding. Shoreline erosion, and more frequent storms combined with SLR will increase vulnerability of coastal sites in the future. All endangered sites cannot be protected, therefore the results of the study should be of particular interest to historic preservation planners, cultural resources managers, Indigenous community leaders, and scholars to prioritize resources, develop the most effective preservation strategies, and plans for reconnaissance, survey, or data recovery from threatened sites and landscapes.