The ‘Holwerd aan Zee plan’ was developed by local residents to give a boost to the economy of the north-east part of Friesland province and at the same time improve the environmental quality of the region. The plan envisages greater linkage between the Wadden Sea and the hinterland, with nature development along the Wadden Dyke creating the impression of a lake, giving the area more appeal for residents and tourists alike. The project will certainly bring concrete economic benefits to the population but there will also be costs, and Friesland Provincial Executive and the Holwerd aan Zee Foundation therefore asked CE Delft to carry out a Social Cost-Benefit Analysis (SCBA).