Tehran Aquifer Vulnerability Assessment Using ARCGIS and Drastic Index

Groundwater is the main source of water in arid in arid and semi-arid regions. Therefore, pollution of groundwater is a major issue because aquifers and the contained ground water are inherently susceptible to contamination from land use and anthropogenic impact. In recognition of the need for effective and efficient methods for protecting groundwater resources from future contamination, scientists and resource managers have sought to develop aquifer vulnerability assessment techniques for prediciting which areas are more likely than others to become contaminated as a result of activities at or near the land surface. This research is focused on the evaluation of Tehran groundwater vulnerability to pollution .Among several assessment methods, DRASTIC has been selected for this stubby. Tehran aquifer is nearly covered by Tehran city the Capital and largest city of Iran. Almost fifty percent of city drinking water is supplied from groundwater. Therefore, vulnerability assessment of the aquifer to domestic pollution is important for protecting the water quality and sustainability. ArcGIS has been used to overlay and calculate different layers and obtain the vulnerability map. In addition, groundwater balance has been evaluated in order to obtain the net recharge parameter in DRASTIC index. About 50 percent of the aquifer has been classified as moderate and almost 20 percent has very low and low vulnerability potential to pollutions.

Keywords:

groundwater , vulnerability , contamination , GIS , Tehran