New coastal engineering professor at the Delft University of Technology, Stefan Aarninkhof, is calling for the Dutch government to increase beach nourishment activities across the country.
In his inaugural address on 10 May, the professor said that based on the latest studies on melting sheets, the Dutch government should better prepare for a sharp increase of beach nourishment projects.
Aarninkhof questioned whether the current nourishment strategy for the Dutch coastline, is fit for the future when sea level rise will force a sharply increase of the volume of sand supplements. He plead for a study on the efficiency of mega coastal sand supplements.
“The Dutch coast is largely erosive and a retreat of the coastline endangers the strength of the dunes as a sea-defense. In order to defend the low-lying hinterland, it is essential for the Dutch flood control to keep the coastline in place,” said the professor.
Therefore the Dutch national public works, Rijkswaterstaat, annually nourishes the coast with 12 million cubic meters of sand. These supplements aim to maintain the coastline of 1992. According to Aarninkhof it may be necessary to increase this volume drastically as the latest studies on the melting of polar ice indicate a faster rise of the sea level.
Aarninkhof noted that many recent studies indicate a faster ice melting. He advised the Netherlands to look into more dramatic climate change scenarios more closely to be able to increase the beach nourishments at a much quicker rate.
Rijkswaterstaat gained much efficiency in the past by supplementing the sand on the fore shore, rather than on the beach itself. In line with such an innovation of beach nourishment, Aarninkhof mentioned the mega nourishment ‘the Sand Motor’. In 2005 20 million cubic meter of sand was placed on the foreshore of the coast of The Hague during one mega nourishment.
Natural elements, such as wind, tide and currents, are now displacing this sand along the coast, strengthening the coastline as a flood defense. Aarninkhof is of opinion that such a long term strategy may bring private parties to join similar mega nourishment projects for reasons of nature or coastal development.