A probabilistic approach to borrow sediment selection in beach nourishment projects

A probabilistic approach is used to assess borrow material stability on artificially nourished beaches. A stability factor (sf) is attributed to each grainsize fraction of the native sediment based on its cumulative curve. Sum of these sf, weighted with the frequency of each grain size fraction of the borrow material, gives the Stability index (Si) with values between 1 (completely stable) and 0 (completely unstable). Unlike other methodologies, the present one is not based on textural parameters requiring sediment lognormality. It considers the complete sediment distribution and computes stability for any borrow vs native material. A detailed example of applying the method is provided and three other study cases are presented in which Si proved to be an effective parameter to address appropriate selection amongst different borrow sediments.