Integrated water resources management of the Hydrogeological Unit "Eastern Mancha" using Bayesian Belief Networks

Included into the objectives of the EU Water Framework Directive (Directive 2000/60/EC) there are the correct management of the water resources and the involvement of the stakeholders in the decision process. Bayesian Networks, mathematical models based on the probability theory, have been used recently to solve environmental problems. This methodology meets the relevant requirements to the effect that it is fully comprehensive and integrated, as it deals with the water resource as a whole and encourages the participation of all those people and groups who are somehow involved in its use or management. A Bayesian Network was developed by means of stakeholders participation which is intended to be useful in the decision-making process related to water resource management in the Hydrogeological Unit "Eastern Mancha". The main problem in the region is the risk of overexploitation of the local aquifer, brought about by a considerable increase, over the last 25 years, in the surface area of irrigated arable land. The results offered by the tool show that the current situation is non-sustainable concerning the aquifer exploitation. There are several ways to solve this situation. The first one could be decreasing the current volume of ground water for irrigation, but this solution would not be welcome by the farmers due to losses of income. The second one is replacing groundwater for irrigation by surface water, where the main problem would be the considerable expenses in infrastructures.