Source Control
Wastewater Division staff have developed a Source Control Program designed to protect the City's wastewater assets.

One element of the Source Control Program is the assessment of industrial wastewater dischargers. Industrial waste is a generic term for any waste material generated by a commercial, industrial, or other non-residential activity. The goal of this program is to identify and regulate discharge that is, by nature, hazardous and poses a risk to the integrity of the wastewater system.

Another element of the Source Control Program is reduction of the discharge of fats, oils and grease (FOG) to the wastewater system. Up to 50% of all wastewater system overflows are caused by accumulations of FOG associated with food preparation. FOG sticks to the inside of wastewater pipes and builds-up over time to cause blockages. These blockages cause backups and overflows of raw sewage that can enter homes, businesses, and the environment.


It is unlawful to discharge any of the following in the wastewater system: any water or waste which contains >100 parts per million by weight of fat, oil or grease; any flammable or explosive liquid, solid, or gas; any solid or viscous substances capable of causing an obstruction to the flow of sewers; any waste containing toxic or corrosive substances.

Contact: 425-556-2800

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