This paper presents a procedure for decision analysis in water use conflicts among irrigators. It seeks feasible compromise term among decision makers by using optimal results for different proposals of solutions. The process is developed by applying the Graph Model for Conflict Resolution. The case study is the existing conflict among Coqueiros canal water users. This 45 km canal belongs to a complex irrigation and drainage canal network and it is located at Campos dos Goytacazes municipality, in the northern region of the State of Rio de Janeiro. Its basin has a potential irrigable area of approximately 14,000 ha. Six hypothetical scenarios have been built, each one corresponding to different alternatives to the conflict solution. In addition, two different tendencies were adopted by the Management Institution (MI) in order to take care of the conflict. The first tendency takes into account that the MI has no explicit preferences for any of its actions. As for the second one, the MI shows explicit preferences for the scenarios which provide more income taxes. Some scenarios that reached the state of equilibrium were analyzed to provide solutions to the conflict.

Decision Process in a Water Use Conflict in Brazil

The understanding and modeling of human behavior in conflict situations is a challenge that researches investigate by developing, modifying and applying computational models. This paper aims to analyze how changes in the strategies of the various groups involved in a water use conflict can influence the decision process. The case study is an irrigation system supplied by a main canal in Rio de Janeiro State, Southeastern Brazil. Conflicts arise due to hydraulic constraints of the canal, resulting in water unavailability for some irrigators or damage to potentially irrigable lands caused by adjacent floods. The investigation strategy has been developed, considering three groups of irrigators. They can be geographically identified over the main canal's hydrographical limits. Six different scenarios are considered to analyze the conflict. These scenarios are built taking into account six different policies of water conveyance. Additionally, the decision of the state government related to water charging has been considered. The final decision is taken by the management institution of the canal which also has two different tendencies: to opt for the scenarios providing highest net profits or to be impartial in the final decision. The Graph Model for Conflict Resolution, which solves non-cooperative games based on graph theory, was adopted to evaluate all these strategies. The results show that, according to the level of exigency of irrigator groups, state government and management institution, the conflict can in fact, be resolved.

Investigating Strategies of an Irrigation Conflict

This paper presents a procedure for decision analysis in water use conflicts among irrigators. It seeks a feasible compromise among decision makers by using optimal results for different solution proposals. The process is developed by applying the Graph Model for Conflict Resolution (GMCR). The case study is the existing conflict among Coqueiros canal water users. This 45 kilometer canal belongs to a complex irrigation and drainage canal network and it is located in the Campos dos Goytacazes municipality, in the north of Rio de Janeiro State. Its basin has a potential irrigable area of approximately 14,000ha. Six hypothetical scenarios have been built, each one corresponding to different alternatives for conflict solution. In addition, two different tendencies were adopted by the Management Institute to take care of the conflict. The first tendency takes into account that the MI has no explicit preferences for any of its actions. As for the second, the MI shows explicit preferences for the scenarios which provide more income tax.. Several scenarios that reached the state of equilibrium were analyzed to allow the determination of solutions to the conflict. Nevertheless, the only scenario which presents a feasible solution is the one that foresees water allocation by quotas, without discharge constraints along the canal and it does not require economic interferences by the State Government. Key-words: water resources planning system, conflict analy-

Raul Dorfman

Papers

Aplicação da teoria dos jogos para redução dos prejuízos agrícolas decorrentes de déficit hídrico