Assessment of Groundwater Quality in UMM ER Radhuma Aquifer (Iraqi Western Desert) by Integration Between Irrigation Water Quality Index and GIS

Abstract

As groundwater is a vital source of water for domestic and agricultural activities in Iraqi Western Desert area due to lack of surface water resources, groundwater quality and its suitability for agricultural usage was evaluated. The aim of this study is to develop decision support tools for identifying the optimal locations of groundwater in terms of quality to meet the future demands in the western desert area. In order to assessment the groundwater quality for irrigation purposes in a way of high accuracy, the irrigation water quality index (IWQI) will be considered and developed(integrated with GIS) in this study to classify groundwater of the Umm Er Radhuma unconfined aquifer within Iraqi western desert area. For this purpose, 30 wells distribution within study area were chosen to take water samples during two periods (wet and dry season 2010) and analyzed for pH, electrical conductivity, total dissolved solids and major ions. Results suggest that, the use of GIS and water quality index (WQI) methods could provide a very useful and efficient tool to water resource management.The results analysis of (IWQI) maps confirms that: over 80% of the groundwater in study area falls within the ‘‘Severe restriction (SR)’’ and ‘‘High restriction (HR)’’ categories in dry period . This percentage reduced to 60% in wet period due to the dilution of water from rainfall. So, the groundwater from the south-eastern of the Umm Er Radhuma unconfined aquifer should be used only with the soil having high permeability with some constraints imposed on types of plant for specified tolerance of salts.