Advice on Options for Sand Dune Management for Flood and Coastal Defence Volume 1: Main Report

This report for Natural Resources Wales aims to inform advisors, managers and regulators concerned with balancing the goals of coastal dune management for coastal protection and biodiversity. It tackles the problem of dunes becoming over-stabilized by vegetation (often deliberately, for coastal protection) leading to loss of biodiversity.

The main report is based around an assessment of 87 dune systems in Wales, but also contains a more widely applicable review of the methods available to manage coastal dunes, and their suitability in different contexts. It concludes that dune management should consider both the shoreline management policy and the multi-functional importance of an individual dune system. ‘Hold the Line’ should not mean that a dune should remain fixed at all costs. A more dynamic and integrated approach based on a healthy dune system is needed, allowing erosion followed by recovery of embryo dunes, and avoiding engineering measures which interfere with natural interactions between beach and dunes.

The report presents several ‘soft’ management intervention techniques which can effectively limit rates of frontal dune erosion and/ or encourage dune recovery. Where natural processes permit, these techniques can be used to encourage seaward movement of the dune line, protecting against storms. The six most common dune management techniques used to deliver an overall policy of Hold the Line (excluding large-scale beach nourishment and hard engineering) are summarised in the last appendix, with their pros and cons, and cost indications.