Determination The Suitable Locations for Drilling Wells for Irrigation purpose by using Geographic Information System (GIS

Abstract

This study was conducted for the purpose of study and analysis of groundwater in the Karbala Governorate. Relied on a set of data and maps that relate to groundwater, topography and geology of the region in addition to 60 wells were distributed randomly in the region, all of this data has been entered in GIS environment to performance geometric and digital processing for it and completion of the analysis and extract the results from it.After conducting all necessary analyzes has been produced digital map that shows the best places to drill wells for irrigation in the region, depend on the topography of the region, basins and streams, sodium ratio and the proportion of dissolved salts in the groundwater in addition to the depths of those waters.where , the best place to drill wells was selected in the areas which has a little slopes because it contain high proportion of groundwater in addition to the sodium ratio in these areas does not exceed 40%, and this ratio consider good for irrigation, as well as the proportion of dissolved salts which range from 2,000 to 5,000 ppm and Although the height of this proportion , but the nature of the soil in the area and depths of groundwater led to use this water for irrigation , where it was observed that the soil of the region contain a high percentage of sand, in addition to the groundwater depths greater than 5 meter and this led to lack of water and salts accumulate in the plant root zone. Also three-dimensional map has been produced for the aquifer and the depths and thickness of the aquifer groundwater in the area.