Skip to main content

About the King County Industrial Waste Program

The King County Industrial Waste Program (KCIW) regulates approximately 650 commercial and industrial customers that discharge wastewater into King County’s regional wastewater system. KCIW functions under the County’s Wastewater Treatment Division (WTD) as a delegated industrial waste pretreatment program.

KCIW is required to meet the National Pollutant Discharge Elimination System (NPDES) permit requirements for the division’s wastewater treatment plants. Visit our Business Information page to learn about the industries that are regulated under the Industrial waste Program.

Staff in the King County Industrial Waste program provide the following services (select the arrow icons to learn more about each of these areas):

Many companies must pretreat their wastewater before they put it into the sanitary sewer system and comply with reporting, monitoring, and discharge requirements. Companies that violate the rules receive penalties. KCIW is required to publish the names and violations of companies who are in “significant noncompliance” and/or receiving fines in a local newspaper. Our goal is to get companies back into compliance so they do not cause further harm.

Businesses are required to collect samples of their wastewater and send in the results to KCIW. We conduct about 400 inspections each year and collect 1600 samples for analysis.

KCIW issues five types of approvals to discharge waste to our system: 

  • Verbal Authorization 
  • Letters of Authorization 
  • Minor Discharge Authorization 
  • Major Discharge Authorization 
  • Discharge Permit

The type of permit we issue depends on: 

  • The type of industrial process 
  • Volume of water being sent to the sewer 
  • Whether the discharge will be short or long-term 

On our website, you will find technical assistance resources, back issues of our semi-annual newsletter, and fact sheets. You can also sign up to receive our newsletter in your email box. 

Our Rewards and Recognition Program recognizes industrial wastewater dischargers in King County that meet or exceed wastewater discharge permit requirements.

  • Our team researches the potential effect of growing industries on the wastewater system. We do this to try and get ahead of any new discharges that might prevent our system from working to protect human health and the environment. 
  • Investigate problems identified by our treatment plants when they discover abnormal amounts of chemicals or other problem substances in the wastewater coming to the plants.  

Is my business a discharger of industrial wastewater?

If your company or facility sends wastewater to the King County sewer system during manufacturing, remediation, cleaning, or rinsing processes, it is most likely industrial wastewater* and is subject to local, state and federal regulations, and you will be required to get discharge approval from the King County Industrial Waste Program.

*This waste differs from residential household wastewater which includes domestic sewage from toilets, showers, washing machines, and other activities.

What is industrial waste?

As defined by King County Code , "'Industrial waste' shall mean any liquid, solid, or gaseous substance, or combination thereof, resulting from any process of industry, government agency, manufacturing, commercial food processing, business, agriculture, trade, or research, including but not limited to the development, recovery, or processing of natural resources, leachate from landfills or other disposal sites, decant water, contaminated non-process water, and contaminated stormwater and ground water."

Industrial wastewater discharge approvals

The Industrial Waste Program issues several types of discharge approvals and works with dischargers to determine which approval is needed. Approvals include permits, discharge authorizations, discharge letters, and verbal approvals. The type of approval is determined by the volume discharged, the nature of the business, the characteristics of the wastewater, and the potential risk to the treatment plant. The program gives specialized approvals for some types of discharges.

Learn more about the permit application on the application forms page

How does my business or facility get approval to discharge?

Prior to discharging industrial waste to the King County sewer system, all dischargers that generate and dispose of industrial wastewater should contact the Industrial Waste Program. Staff will discuss your operation with you. Potential dischargers will be sent a permit application package if a written discharge approval is necessary. The permit application is available on this site - but strongly consider discussing your operation and what information may need to be submitted with KCIW staff prior to developing an application.

How much advance notice is needed to obtain a new approval to discharge industrial wastewater?

The time it takes (either 60 or 90 days) to obtain approval to discharge depends upon the type and amount of wastewater a company discharges to the sewer.

Companies that are planning to start discharging industrial wastewater from a new facility, or to start discharging wastewater from a new process at an existing operation, must file applications according to the following criteria: if the proposed operation will be subject to a federal categorical pretreatment standard, for instance metal finishing or centralized waste treatment, then the application must be filed at least 90 days prior to the start of discharge.

All non-categorical dischargers must apply at least 60 days prior to the start of discharge.

The sooner applicants contact KCIW to discuss their applications, the better!

How much does it cost to discharge industrial wastewater to King County?

There are fees associated with the issuance and renewal of wastewater discharge permits, discharge authorizations, and Letters of Authorization. Fees are structured to cover the costs of drafting and issuing approvals. These fees are over and above the base sewer fees charged by the local sewer agency or monitoring charges by King County. There may also be a surcharge fee for high-strength waste.

View the current King County Industrial Waste Program fees

What are the penalties for discharging industrial wastewater without following law?

Managing wastewater properly is good for the water, the environment, and community health - and for businesses within the community. The Industrial Waste Program conducts enforcement activities for polluters as a deterrent to the high costs of polluting.

Businesses or individuals who illegally discharge substances to the King County sewer system must pay for any damages and may be fined up to $10,000 per day per violation. Companies or facilities may also be charged for increased monitoring of their discharges and may be required to install upgraded equipment.

Any business or facility receiving a fine will have its name and polluting activities published and prominently displayed in an advertisement in the King County newspaper with the highest distribution.