The Swiss city of Schaffhausen commissioned us to complete the planning and construction of a two-stage flood retention basin on the Dachsenbühlbach creek located near the Schweizersbild sports facility. In keeping with the city's policy of responding proactively to hazards associated with climate change, the project is aimed at protecting against floods that statistically reoccur at a 300-year interval. We built the final dam as a predominantly encased concrete wall that follows the contour of the terrain. The outflow is regulated with a debris rack.