Business Source Control

Monitoring and Inspections

Non-residential customers such as food-processing establishments and industrial users are provided with technical assistance visits from the City’s Source Control Technician. The Technician provides advice and recommendations to aid businesses in making sound decisions regarding waste reduction, effluent discharge, and regulatory compliance. Inspections may involve assessment of new and existing fats, oils and grease (FOG) control devices as well as CCTV (closed circuit television) inspections of pipes downstream of business wastewater outlets.

Monitoring is another aspect of a Source Control Program that can help achieve a reduction of problem discharges to the system and encourage proactive maintenance of the wastewater system. Monitoring occurs on an as-needed basis as determined by discharge characteristics and includes analysis of the constituents in wastewater produced at businesses.

Fats, Oils, and Grease (FOG)

One element of the Source Control Program is reduction of fats, oils and grease (FOG) discharge from food service establishments (FSE's). This program regulates the waste stream from over 300 FSE's through outreach, inspection, and enforcement.

Up to 50% of all sanitary sewer overflows are caused by accumulations of fats, oils and grease (FOG) on the inside of wastewater pipes. FOG comes from many sources: meat, lard, cooking oil, shortening, butter & margarine, food scraps, baked goods, sauces, dairy products, salad dressings, mayonnaise, gravy, etc. FOG is typically discharged to the wastewater system through kitchen sinks and dishwashers.

FOG solidifies and builds-up over time to cause blockages. These blockages cause backups and overflows of raw sewage that can enter businesses, homes, and the environment. This can lead to human contact with disease-causing organisms, environmental damage, increased maintenance costs and higher wastewater utility rates.

Furthermore, business owners may be held liable for all clean-up costs related to a sanitary sewer overflow. Such costs can include damage to adjoining personal property, parking lots, streets, wastewater pumps, piping, and treatment plants.

The best way to prevent sanitary sewer overflows is to keep FOG out of the wastewater system in the first place. There are several ways to accomplish this: 
  • Teach your employees the importance of controlling FOG. Consider posting “No Grease” signs above your sinks and dishwasher.

  • Maintain your grease removal device (GRD) to keep the accumulation of FOG and food waste less than 25% of the volume of the device. Record self-cleanings on a simple maintenance log that includes the date, the amount of grease, and the cleaner’s initials.

    GRDs are designed to catch FOG before it enters your wastewater system. Grease interceptors are large devices that are usually located outside your business. Have your grease interceptor cleaned every 90 days at a minimum. Grease traps are usually found under or near sinks in your kitchen. Self-clean your grease trap at least once per week and have a contractor clean it every 60 days.


Yuck! Avoid this with proper maintenance of your grease removal device.

FOG spills inside and outside of your business should be cleaned-up immediately. It is your responsibility to maintain a spill kit and use an outdoor spill prevention and clean-up plan.


These drums should have tightly-closed lids. This spill needs to be cleaned up!


Grease should be wiped with a dry paper towel or
scraped off dishes like these prior to washing them with water.

  • Dry wipe (with a paper towel) or scrape grease and food scraps from pots, pans, cooking equipment, and dishes prior to pre-rinsing or washing. Grease and food scraps can go into your compost pile, yard waste container, or trashcan for disposal.

  • Businesses may request up to two 96-gallon food recycling carts to be picked up twice a week by Waste Management at no additional charge. This service, geared for those businesses with large amounts of food or other organics in their waste stream, can result in a smaller garbage dumpster – and a smaller bill! Collected materials are taken to Cedar Grove and turned into compost for landscaping.

  • Acceptable items include: meat, cheese, bones, vegetables, fruit, and food soiled paper. For more information, review the Commercial Food Recycling Guidelines or call: 425-556-2897.

  • Remove your garbage grinder and install a solids interceptor. This will reduce the amount of grease and food waste that will accumulate in your GRD and contribute to blockages in your business’ side sewer pipe.

  • Install and maintain screens in all floor and sink drains to catch any grease and food scraps you’ve missed with your paper towel or scraper.
  • Recycle your food scraps and cooking oil.

  • Hire a contractor to maintain the vent hood and filters and dispose of the waste properly.

  • Wash all floor mats, grills, and greasy kitchen equipment in a sink that goes to a grease trap or interceptor. Never wash these items outside where wastewater can flow into a storm drain. The City has designed a Poster to display many of these concepts, that you may find helpful.

Industrial Wastewater

As another element of Source Control, the City is now assessing 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.

The City of Redmond Source Control Program has partnered with King County. The King County Industrial Waste Program is intended to protect the Publicly Owned Treatment Works (POTW) and focuses on companies that discharge wastewater during manufacturing, remediation, cleaning, or rinsing processes. King County has a federally mandated Industrial Pretreatment program and currently oversees nearly 30 permitted dischargers within the City of Redmond.

In addition, the City's Source Control Program will also be aimed at working with smaller dischargers to ensure compliance. Outreach efforts will be designed to educate owners and characterize waste constituents.

Follow this link for details on business garbage and recycling in Redmond.

For more information about hazardous waste at your business including reducing waste, recycling, and disposal visit the King County Local Business Hazardous Waste Management Program.

Contact: 425-556-2800

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