The increased demand for marine aggregates can lead to a growing impact on the seabed and the organisms that depend on it (macrozoobenthos and demersal fish). Traditionally, these impacts are considered to be negative, though inevitable. Therefore, permitting authorities prescribe that impacts need to be minimized in time and space (traditionally, in the Netherlands permits did not allow for extraction deeper than 2 m below the undisturbed seabed; recently, based on new understanding permits allow for deeper sand extraction, up to 20 m below the seabed).
Sand extraction sites are often selected based on economic reasons, such as the amount of suitable sediment and sailing distance. The impact on nature is considered by opting for a site with a poor to moderate ecological value. The post-dredging value of a site, however, is rarely considered. This means that opportunities for habitat enhancement through sand extraction may be missed.
Looking at these practices, from an environmental point of view there is room for improving the way that sand extraction sites are currently licensed and operated. Opportunities for ecological development can be created not only through the geographical choice of the location and the extraction depth but also through ecosystem-based landscaping of the seabed during the sand extraction process. Current legislation and policy concerning the marine and coastal environment, however, are still based on conservation principles, rather than on ‘dynamics’ and ‘development’, and they don’t pertain to one habitat replacing another.