Abstract:
The H&R wave overtopping model, originally developed for sloping structures, is employed in
a number of operational coastal flood forecasting and warning systems. This paper describes
the first step in a project to extend the model to encompass vertical structures. Use is made of
the CLASH database for the purpose of checking whether it is appropriate to simply
extrapolate the existing formulae for the model’s empirical coefficients beyond their strict
ranges of applicability. The outcome is encouraging. Despite the fact that, in general, the
model tended to underestimate the higher wave overtopping rates, it was reasonably accurate
in describing the lower overtopping rates which normally trigger flood warnings, suggesting
that it may be worthwhile pursuing the task of calibrating and validating the H&R model for
vertical structures.