The influx of salt water on the water resources system of AZARSHAHR plain and its effects on supply needs of the next 20 years

When the water supply system faces serious problems and crises, it is necessary to identify the root causes and the history of the problems, in order to provide an effective solution. Measures can be effective when timely; otherwise they will have a high cost and less impact. In this paper, the history of salt water influx into the water resources system of AZARSHAHR plain was identified using the statistical analysis and GIS, and the reason for the ineffectiveness of the actions has been discussed, and ultimately evaluated its effects on supply the demand of the next 20 years in WEAP software. Changes in systems are usually gradual until these small effects accumulate and rise above the threshold of tolerance. In this study, using groundwater quality data, groundwater water level and Lake URMIA level, the date of the influx of saline water into aquifer was identified in late 2000 after five years of drought. Using the neural network, resource changes for the next 20 years are anticipated and according to the demands, assess the effects of change in supply the demand of the next 20 years will be evaluated in the WEAP software based on the water Year scenario. As a result of five consecutive droughts, the extraction of the aquifer have increased rapidly, and since no significant structural measure, and in particular, non-structural measures such as transparency (full access to data), and the participation of all stakeholders in solving the problem and eventually lack of adequate responses to the lack of effective measures, the cumulative effects of these 5 drought years have brought about a big change in the system. Due to this change, the system's capacity was severely affected and the possibility of supply the future demands in the plain would not be possible, which seriously threatened the economic and social sustainability of the region. A large change occurred on the AZARSHAHR water supply system after five consecutive drought years at the end of 2000 with a large influx of saline water from the Islamic island to the aquifer. The structural measures undertaken were so small that failed to neutralize the effect of this large change. In practice, salinity of groundwater has expanded by the year 2014. If it wants keep the crop of 2015-2016 in the next 20 years, there will be a deficit of 16 to 18 million cubic meters in supply of agricultural demands. With management of agricultural water demand, with the implementation of Drip irrigation system In the form of stepping up (every 5 years 5%) will reduce this deficiency to 13 million cubic meters at the end of the 20-year period, with an annual decline of 1% of arable crops along with management Agriculture demand will reduced this deficit to 10 million cubic meters at the end of the 20-year period.