Using Soil Water Balance to Estimate Recharge of Underground Water in Central Sulaimani Province

Abstract

In this study, we estimated the recharge of underground water by using soil water balance in the Sulaimani Province. Based on recorded data in three metrological centres, including Sulaimani, Bakrajo, and Bazyan from 2009 -2021. We found an estimated rate of potential evapotranspiration by using the FAO-Penman -Monteith equation by CropWat Ver.8 Software Programs. Based on this estimate, we found the water deficit and water surplus months in the study area. Moreover, grounded on (SCS-CN) model in the mentioned area which would be divided into 8 different ( CN). Accordingly, an estimate was obtained for the rate of runoff water per month of a calendar year. Finally, we found the amount of rainwater that would take part in the recharge of underground water throughout each month and over years. In this study, we also used statistical analysis of quantitative mathematical results to find amounts of underground water in the study area. Besides, we used (ArcGis10.8) program to create maps for various purposes. In conclusion, we successfully discovered that it is possible to develop a scientific strategy to collect rainwater and replenish underground water sources and protect them by finding out amounts of underground water recharge in the Formation zone that would be 104.2 mm. Importantly, (CN-57) which is located in the district of Bazyan (Khormala -Sinjar Fn.) has the highest amount of underground water recharge that is equivalent to 210.2mm of the total amount of the precipitation equivalent to 32% of the annual sum of rain.