Assessment of Water Supply and Use in the Zayandeh-Rud River Basin, Iran

The Zayandeh-Rud Basin (ZRB) is expriencing water stress. It has been the situation for the past 50 years. Basin development is considered normally a three-stage process with a relatively smooth transition between overdraft, water supply management, and optimal allocation. In the ZRB however, five phases of water resources developments (WRD) may be identified, including the trans-basin projects. The Situation in the ZRB does not show an encouraging picture. Increased water supply on each phase of development still fall behind the demand growth. That is the reason why for the past 50 years, the basin remained more or less under water stress. There is no inter-basin integrated water management that shares out the shortages uniformly between different uses, or even within a particular water use. Without trans-basin water transfers, the ZRB basin is unable to meet existing water demands. However, several scenarios also show that even then, the basin will be unable to meet water demands before 2020 as long as the urban, industrial and agriculture sectors continue to grow with the current rate.