Water Quality manages the sanitary sewer collection system, two wastewater treatment plants, and the stormwater system.

The sanitary sewer system includes over 100 miles of sanitary sewer pipes, 22 sanitary sewer pump stations, and two wastewater treatment plants (WWTPs). The City provides sanitary sewer service for Coos Bay and also treats raw sewage from Charleston and Bunker Hill special sanitary districts. The wastewater treatment process is specifically designed to prevent waterborne pollution and ensure that water released into our waterways is treated and in compliance with strict EPA and DEQ standards. WWTP1 is located north of downtown and WWTP2 is located in Empire.

The Fats, Oils, and Grease (FOG) Management Program is a city program to minimize the FOG discharge into the sanitary sewer system by ensuring that FOG pretreatment devices are installed, maintained, and operating in an effective manner.

Water Quality oversees maintenance of extensive stormwater collection and management systems, including three storm pump stations, approximately 48 miles of gravity piping, and numerous natural water bodies including streams, lakes, and sloughs. All stormwater eventually feeds to Coos Bay.