Contain silt, sediment and oil pumped out during dewatering operations. Draining swampy or low-lying areas is a common occurrence in construction. Unfortunately, pumping out the water from these areas also removes a lot of dirt, silt, mud, and debris along with the water. These contaminants can cause problems if they are simply discharged into a storm drain. The Ultra-Dewatering Bag provides an economical and effective solution. By pumping water into the bag, silt, dirt, sand and other pollutants are trapped and filtered so only water escapes to the ground below or nearby storm drains