Almost every year, extreme floods cause enormous damage in floodplains. However, urban development still takes place in these areas. As levees are built up, space for the rivers shrinks. The same patterns of human activity can often be observed in floodplains: values are accumulated there, floods threaten them, levees are built to protect the values, and additional values are accumulated. In consequence, flood risk increases. Continuing patterns of human activity establish a persistent social construction in floodplains which contributes to risk increase. This is clumsy. The analysis of this clumsiness is the objective of this paper. Therefore, social construction in floodplains will be described with the help of polyrationality theory. Then, a reflection on the legal basis for this activity will be made for the German case. This contribution will show that the legal system sustains the social construction, which emerges as clumsiness. Finally, a recommendation for a responsive land policy will be made - one which copes with the clumsy floodplains. It is based on a compulsory insurance against natural hazards.