Estimation and comparison the exploitation amount from ground- water resources under alternative exploitation models and its effect on sustainability: the study of Bahar-Hamedan Plain

Considering the importance of groundwater resources, this study aims to estimate and compare the amount of demand for irrigation water and sustainability of ground water resource, in Bahar-Hamadan plain, under alternative policies and models of exploitation. For this purpose, the water demand function driven from a crop cost function, developed and estimated. The needed data collected from a survey through multi-stage classified sampling method. Results showed that in current condition or government intervention and legal control, the amount of water extracting equals 15855 m3 per hectare. This level of extracting is high and non-sustainable. In contrast, the amount of water extraction for perfect participation by water users in exploitation model, estimated to be equal 9182 m3 per hectare; which could be considered as the best alternative model for decreasing water use and reaching the sustainable allocation of water.