-

Considering the important role of water resources in agricultural production in arid and semi -- arid areas, optimizing the agricultural activities with regard to water scarcity is of utmost importance. In farm activities modeling one must be concerned with balance in supply and demand of water. This article has examined a model that, besides
the provision of an optimal crop pattern, gives rise to the optimal levels of extraction of surface and ground water resources. Results show that, along with reduction in water extraction especially during summer and autumn seasons, with some due modification in important crop acreages, the gross return in agriculture would rise by 1.34 percent. In this situation, if water use efficiency also rises from 60 to 70 percent, with similar modification, there would exist the possibility of 17.1 percent promotion in agricultural gross returns