The tallest plastic sump pumps ever built are handling corrosive, erosive stormwater runoff as part of the Blue Plains, Washington, Advanced Wastewater Treatment system operated for the District of Columbia. The sources at this site deliver large quantities of waste chemicals such as ferric chloride and pickling liquor, plant wash-down water, excess boiler makeup water, rain runoff, and other corrosive and abrasive fluids.

The 20-foot tall pumps were developed after standard metal pumps in service resulted in high maintenance costs. A plant engineering study resulted in a recommendation to specify polypropylene thermoplastic pumps on a planned metal pump replacement maintenance schedule. More than 400 Vanton thermoplastic “Trasher” type sump pumps designed to handle the destructive fluids were utilized. These pumps, sized for sumps from 48 inches to 10 feet deep, are handling waste fluids that include entrained abrasives, silt, sludge and other pump-destroying streams.

Stormwater runoff presented a major problem due to the tremendous depths of the required sumps and the abrasive nature of wastes.