Tahtali Dam Watershed Area is one of the most important potable and usage water sources in Izmir. There are settlements, industries and animal farms in this watershed area. The pollution problem of Izmir Tahtaii watershed areas has been mostly caused by municipal wastes, animal farms and industrial sources. In this study, domestic wastewater flowrates originating from the settlements in Tahtali Dam Watershed Area and from industries were calculated. However, processes waters of industries could not be examined, so, pollution loading of industries originating from processes could not be determined. Existing methods and required methods, which is suitable for disposal of wastewaters in Tahtali Watershed Area, are given.