The wastewater system is comprised of 2 wastewater treatment plants, 40 sewage pump stations and 268 grinder pump stations as of 2022.
The Westside Wastewater Treatment Plant serves the entire City of Bremerton. It began operating in 1985, and provides full secondary biological treatment with 15.5 million gallons per day (MGD) capacity.
The older portions of the city's sewer conveyance systems were designed to convey both wastewater and stormwater and during periods of heavy rainfall these systems would relieve themselves through multiple combined sewer overflow (CSO) sites. The CSO sites are permitted through the Washington Department of Ecology’s NPDES permit. The City completed a concerted effort to reduce these CSOs to meet the stringent requirements of the WA Department of Ecology. The CSO events have been reduced by over 99% and led to the reopening of the shellfish harvest areas in Dyes Inlet.
The Wastewater Division staff has been the recipient of many awards by the Washington State Department of Ecology. They were first awarded the "Outstanding Performance Award" in 1999, and then subsequently from 2005 thru 2021. The Westside Plant has an accredited laboratory through the WA Department of Ecology, and analyzes samples for both treatment plants. The Wastewater Division is staffed with 21 full-time employees, who operate and maintain both treatment plants and sewage pump stations.