Beach-dune modelling in support of Building with Nature for an integrated spatial design of urbanized sandy shores

Abstract

The long-term physical existence of sandy shores critically depends on a balanced sediment budget. From the principles of Building with Nature it follows that a sustainable protection of sandy shores should employ some form of shore nourishment. In the spatial design process of urbanized sandy shores, where multiple functions must be integrated, the knowledge and the prediction of sediment dynamics and beach-dune morphology thus play an essential role. This expertise typically resides with coastal scientists who have condensed their knowledge in various types of morphological models that serve different purposes and rely on different assumptions, thus have their specific strengths and limitations. This paper identifies morphological information needs for the integrated spatial design of urbanized sandy shores using BwN principles, outlines capabilities of different types of morphological models to support this and identifies current gaps between the two. A clear mismatch arises from the absence of buildings and accompanying human activities in current numerical models simulating morphological developments in beach-dune environments.

Deposition patterns around buildings at the beach: Effects of building spacing and orientation

“…for dune widening) (Van Bergen et al, 2021). Such designs need rules of thumb on how deposition and erosion depend on building placement and characteristics (Wijnberg et al, 2021).…”

ShoreScape

“…One way to tackle uncertainty is predicting BwN dynamics over time using computational models. These models are still in their pioneering phase but steadily progressing; becoming more reliable over time (Wijnberg et al, 2021). However, they require specialist knowledge and state-of-the-art modelling skills-plus substantial investment-to achieve a sufficient level of reliability.…”