HYDROLOGIC STUDY FOR THE WATERSHED OF SHWEICHA WETLAND USING REMOTE SENSING DATA AND SWAT HYDROLOGIC MODEL

In arid and semiarid regions, limited water resources is one of the constraints for agricultural activities and urban development. The eastern region of Wasit Province, Iraq suffer from a severe shortage of water resources especially the cities of Badra, Jassan and Zurbatiya. A few studies was focused on the streams that originate in Iraq-Iran borders such as Galal Badra, Tursekh and Swena as important source of water for domestic and agricultural use. This study was investigated the quality and quantity of water and better management of the streams which discharges into Shweicha Wetland. The Digital Elevation Models (DEMs) of Shuttle Radar Topography Mission (SRTM), the land use/cover of Landsat classified images by The National Geomatics Center of China, the soil dataset of Food and Agriculture Organization of UN (FAO), and the weather dataset of Climate Forecast System Reanalysis (CFSR) were applied into the Soil and Water Assessment Tool (SWAT) model, the model was ran for the period from 1/1/2000 to 31/12/2013 on daily time step of simulation. Due to lack in observed data such as flow or sediment the model was not calibrated with ± 20% error in prediction. From the results, the area of Shweicha Watershed is 21355 〖km〗^2 , 59.6% of this area inside Iraqi borders the remained in Iranian borders. According to the model prediction, the average income of surface runoff entered to Shweicha Wetland for the simulation period was about 5.5 m^3/sec with maximum peak of 5510 m^3/sec on 29/1/2013 and the simulated sediment yield from the region of study is highly related to the peak amount of surface runoff. The region considered, highly sediment production because the barren land dominate 43% of the total watershed's area. Finally, it is recommended to store water before entered to Shweicha Wetland and find best way to prevent deposition in desired lake because store the water in Shweicha Wetland decrease the quantity and quality of water.