Agent-based facilitation of water allocation: Case study in the Drome River Valley

The purpose of the 1992 French Water Act is to encourage negotiation and dialogue among local stakeholders within a framework which is very similar to a patrimonial approach. Potential use of models in such post-normal approaches is analyzed. Two kinds of models are compared: one is agent-based, the other follows a more classical approach. They are compared according to their contributions as negotiation support tools. This comparison is based on a specific collective decision process dealing with water allocation at the sub-basin scale, in which authors are involved. Both are used to support collective decision processes through simulation of resource use dynamics. Agent-Based Models entail the broadening of spatial information of actors in the process, revealing inter-connected topics not taken into consideration earlier. This makes it possible to remain relevant, despite the sometimes rapidly evolving stakes. The central point of this paper is the implementation, within a practical application, of theories advocating the use of ABM as a collective decision support system. This application promotes a better understanding of the kind of support ABM provides and the way it does so. This is brought about more by re-framing the discussion and modifying the representation of the system on the part of the stakeholders than by providing specific agreements.