Safety and navigation are two important elements in the multi-objective water management of the Lake IJssel area in The Netherlands including Lake IJssel, Lake Marker and North Sea Canal. In order to maintain these important stakes and to make them explicit, transport over water is treated as individual agent that has to negotiate its objectives within the total operational water management. In this paper, dual decomposition is used in a distributed model predictive controller applied to the main control structures in this area. The controller is evaluated on a realistic scenario simulated on a detailed model of the water system.