Hydrogeological Drought Management Based on HDMI Multivariate Index

In this research, it has been tried to investigate the limitations of using the plain’s groundwater through using the monthly values ​​of discharge of agricultural wells, groundwater level and quality values ​​of electrical conductivity in areas of South Khorasan Province in 2013-2014. In this regard, a combination of groundwater resource index, modified standard electrical conductivity index and standardized well discharge index was used. Finally, hydrogeological drought management index (HDMI) was used to manage the groundwater drought and to investigate hydrogeological drought. HDMI is one of the useful and practical indices in this field that has been less studied. The results of groundwater resource index showed that in the study area, groundwater drought is clearly seen in the southeastern regions of the study area. Hydrogeological drought management index in the studied area showed that operation of groundwater in most of the studied area has a problem and operation of groundwater in these areas should be limited. About 86% of the studied areas are in limited operation condition, 10% are in problem-free operation condition and 4% are in non-operation condition. In general, the results of hydrological drought management index at the study area indicated that this index has high ability to provide an aquifer management and has a great help to water managers in the country. Relying on the results, it is possible to restrict water use at the aquifer and manage the water delivery.