The synergy between flood risk protection and spatial quality in coastal cities

Abstract

Coastal regions throughout the world are subject to flood risk challenges. This paper concentrates on the Netherlands; its coastline fulfils an important role in the protection of the Dutch delta. Due to the expected sea level rise, part of the Dutch coastline will have to be reinforced. Along most of the sparsely occupied coastline, the space needed for the reinforcement of the flood risk protection infrastructure can be found easily, either on the seaside or inland. However, some segments of the coastline have been built upon and are difficult to reinforce; buildings have limited the adaptability of the originally flexible coast. One of these locations is Scheveningen, a borough of the city The Hague and a seaside mass-tourism resort operating on a national scale. It is difficult to reinforce the borough’s flood risk infrastructure without significant restructuring. In addition to water-safety issues, Scheveningen faces social-economic challenges and needs a qualitative programmatic and spatial impulse. An integrated approach to spatial and flood risk design is essential to come to a qualitatively as well as functionally acceptable solution for multifunctional flood defences. This paper describes and demonstrates the approach and application of an integral ‘research by design’ study for flood risk management and spatial quality in Scheveningen. It is the result of a collaborative effort between spatial designers and flood risk engineers, who worked together in so-called ‘Delta ateliers’. Three different flood risk strategies (‘a sandy shore’, ‘a hard protection body’ and ‘a perpendicular dam’) are used as leading principles for integral designs in which both the spatial assignment as well as the long term flood risk protection assignment are addressed. This results in three different designs that are discussed in relation to their spatial potential and hydraulic efficiency. This applied research by design approach was considered very valuable–even essential–to feed the debate regarding the choice of a flood risk intervention. As a result, this approach will be continued throughout the Dutch National ‘Delta Programme’ that focusses on long term flood risk protection.