Resulting backwash water from existing filters, in the water purification plants, is actually thrown in most cases in water bodies, valleys or discharged into other system without making any benefit from it. The amount of backwash water is well estimated to be in average (3-4%) of purified water amount. Even if this amount is generally not relevant, it can however be considered to be useful in some circumstances, where the source water is rare or there is no water resource in the region at all. Treatment of backwash water depends on the reuse need of it, either for drinking or irrigation purposes, so that the treated water must be in accordance with the water quality standard stated in related specifications. In this research, the resulting backwash water purification plant at Roum Dam near Swaida town has been scientifically analyzed and treated in a plant designed and built for this purpose. In this paper, the results of experiments are discussed; important facts have been concluded and economic feasibility for water reuse was determined.