The projected changes in water status of the Mae Klong Basin, Thailand, using WEAP model

River basin management has become more dynamic and challenging due to increased competition among different water use sectors. Mae Klong Basin is rich in term of water availability, but increasing water demands in future due to inter-basin-based water management policy addressed by the national government may strongly influence the changes in water status. WEAP model was implemented to assess the current water supply and demand situations for this basin. Six different scenarios were established to evaluate the response of the basin to increasing demands under two SRES scenarios A2 and B2. The simulated results have shown that currently the water resources in the basin are sufficient to meet the existing needs in the wet season, but water shortage has occurred in the dry periods of 2014 and 2015 due to less rainfall in these years. The results have also shown that more water shortages have occurred under A2 scenario as compared to B2 scenario. Water shortages have occurred in all the developed scenarios indicating that the basin will face water scarcity particularly in the scenario five where transferring water to the adjoining area is difficult to possibly be implemented. The scenario six where a new hydropower project is proposed is considered feasible under both A2 and B2 scenarios and can help in meeting hydropower demands in the basin. It is pertinent to shape more effective policies and regulations in the basin for effective water resources management in reducing water shortage as well as achieving downstream water needs and power benefit in future.