Water demand management in agriculture and its impact on water resources of Bojnourd basin with WEAP and MODFLOW models

Agricultural and industrial development, degradation of surface water resources, groundwater levels drop are among the major factor causing water scarcity. The integrated management of groundwater and surface waters serves as a solution to cope with such issues. In the present study, using a water resources simulation model WEAP and its adjunction to the groundwater simulation model MODFLOW, consumption for Dashte Bojnourd basin was evaluated. Calibration and validation of both models were undertaken based on 6 years (from 2005-06 to 2010-11) and 2 years (from 2011-12 to 2012-13) respectively. Then different management scenarios, including keeping acreage and cultivation area as constant against increasing number of industries, increasing irrigation efficiency in agriculture were considered combinations of the above scenarios alleviate reduce water demand. Under this scenario, projections for a period of 28 years (from 2013-14 to 2040-41) and its effects on water resources of the basin were studied. The results showed that simultaneous applying multiple water management strategies seems to be better than any of its individual states, reducing water withdrawing on various resources. Reliability of water supply in the whole complex scenario, for urban drinking water, rural, agriculture and industry purposes were estimated to be 100, 100, 60.4 and 71.5 percent. To adopt above scenario alluvial aquifer by drop about 0.47 million cubic meters per year could be the relative balance between aquifers exploitation and recharge but limestone aquifer by drop about 6.02 million cubic meters per year need more management actions to have no problems.