Northeaster Risk Index Calculator
The Delaware Northeaster risk index is an assessment of beach/dune erosion potential of a beach as a result of a northeaster. The input data are the deep water wave height of the storm, the predicted (or measured) storm surge at the beach, and the duration of the storm.
Northeasters with ratings of 1 to 2 create significant beach erosion but are not hazardous to structures at the beach. Class 3 or higher are dangerous storms. Class 5 are very dangerous and are similar to the March 1962 storm, which obliterated Delaware's sand dunes and caused $16 million (1962 dollars) in damages.
The model, while generic enough in principle to apply to other beaches, is calibrated for the Delaware shoreline. Therefore it is not applicable to other regions.
Comments: Robert Dalrymple
Center for Applied Coastal Research
University of Delaware, Newark DE 19716