The Effects of Excessive Withdrawal and Recent Droughts on Saveh Plain Aquifer

The aim of this study is to review the effect of excessive withdrawals and recent droughts on groundwater reservoirs of Saveh Plain. The 7 stations were selected between the monthly rainfall data in Saveh plain. In this research, at the time scales of 3, 6, 9 and 12 months for indices CZI, ZSI, MCZI, SPI, the droughts were considered using DIP software. The drop amount of the groundwater level in Saveh aquifer during 22 years (1992-2014) has been approximately 31/86 meters. Statistic of wells during two 10-year periods (1991-2001 and 2001-2011) was taken into account. With two 5-year period, we can conclude that in 1991-1996 years the upper regressed charts and the process is very slow first drop in five years but in the second 5 years has been a steep slope times and in the 2001 to 2011 with the same or slightly steeper slope continues because wells are unauthorized and uncontrolled exploitation. In a review of quality groundwater was used AqQa software that Piper diagram indicates calcic facies is in the study area, and Durov diagram shows a sudden increase in total dissolved solids and close to bicarbonate type that can be due to the formation concerned or leakage from a probable underlying semi-confined aquifer or mixing with another source which requires further reviews.