The paper gives a basic overview of the U.S. government's involvements in developing countermeasures for the abatement of combined sewer overflow pollution. Abatement or prevention of pollution stormwater runoff and combined sewer overflows is one of the most challenging areas in the sanitary engineering field. The full impacts of 'marginal' pollution, particularly that caused by uncontrolled overflows, must be recognized now and planning initiated to improve sewerage system efficiencies and bring all wastewater flows under control. Efforts devoted to improving sewerage systems will pay significant dividends in complete control of metropolitan wastewater problems and pollution abatement.