Investigating the Impact of Price Policy and Investment in Water Saving Technologies, on the Deficits of Groundwater Reserves and Social Costs in Khorasan Razavi Province

Abstract In order to compare the effect of water pricing policy with increasing irrigation efficiency and investment in water and sewage technology, on reducing the deficit of groundwater reservoirs "DGR", production, net imports, net social benefits and income of farmers in Khorasan Razavi province, Five cities including Mashhad, Sabzevar, Neyshabour, Torbat Jam and Torbat Heydarieh were selected and the impact of these policies was studied using a positive mathematical programming model (PMP_GME). The analysis of the effect of rising water prices showed that although this policy has different results in different regions, making it impossible to implement, farmers' income is reduced from 19 to 98 and an average of 63 percent and increases social costs by 50 percent. So that the cost per cubic meter of saved water will be 5750 Rials. By increasing the efficiency of water transmission and distribution and without increasing the area under cultivation, the DGR is reduced by an average of 83%. The farmer's cost will be 300 Rials and the social costs will be 700 Rials per cubic meter. If the total irrigation efficiency is corrected to its potential, the DGR is reduced by 106%. If the increase in efficiency is accompanied by lack of control over the level of crops, although the production increases, but in conditions, the DGR are rising, but on average they fall by 53%. Replacing new systems instead of old and increasing the irrigation efficiency until to potential level without increasing the level of cultivation, reduces the DGR by 94%. But without increasing water application efficiency, only 63% of the DGE is corrected. It is therefore suggested, in place that the efficiency of transmission and distribution of water has increased, government reduce the extraction of ground water, proportional of increase in irrigation efficiency. Also, in critical areas, providing facilities for new irrigation systems be conditional on reducing water harvesting.