Determination of the Optimal Groin Length on a Sandy Multibar Shore of a Nontidal Sea: Case Study of the Hel Peninsula, Poland, South Baltic Sea

Abstract

In this paper, we present a simple theoretical method of determining the optimal groin length on a sandy multibar shore of a nontidal sea. Example computations for the seashore of the Hel Peninsula (Poland, south Baltic Sea) are provided. The proposed unsophisticated method, which consumes little time and is thus innovative, is based on calculations of the mean annual sediment transport rate and a determination of the width of the surf zone. The reliability of the theoretical modeling results was demonstrated, as well as their compatibility with the features of the groin system designed and constructed along this stretch of the shore a few decades ago. Long-term field observations in the village of Kuźnica have shown that such a system effectively supports and supplements the artificial shore nourishment in the considered region. The method can be applied to other sandy and multibar shores of nontidal seas.