Washington State Department of Ecology

Illicit Discharge Detection and Elimination (IDDE) Program Resources

Resources and guidance on IDDE for local stormwater managers.

IDDE Program Guidance

Municipal Stormwater General Permits: Getting Us to Clean Water by Finding and Fixing Problems
Frequently Asked Questions: Reporting Discharges and Spills under the Municipal Stormwater NPDES Permits - September 2009.
Frequently Asked Questions: Municipal Stormwater Permits and Compliance with Standards
Center for Watershed Protection Manual: Illicit Discharge Detection and Elimination (EPA website)
Car Washing and Stormwater Permit - resources and information
Frequently Asked Questions About Residential Car Washing and Stormwater
Ecology staff prepared the following IDDE Field Training Guidance Elements Checklist to provide permittees and trainers with a broad outline of recommended elements for an Illicit Discharge Detection and Elimination training program for field staff.
Vehicle and Equipment Washwater Discharges/Best Management Practices Manual is Ecology’s guidance on the collection, treatment, and discharge of washwater for cars, trucks, light or heavy equipment.
Video on Finding and Fixing Illicit Discharges - Across our urban and suburban watersheds, hidden culprits are polluting our waterways. Watch this Center for Watershed Protection video to find out more about Illicit Discharge Detection & Elimination (IDDE) -- the process of finding and fixing these hidden stream polluters.

IDDE Regulations Guidance

IDDE Materials from Permittees

The following materials were prepared by Washington state municipal stormwater permittees to support their permit implementation. The permittees have made these materials available to others to modify for their own use. Ecology has not formally reviewed and approved these materials.

The City of Pullman's IDDE Success Story "Stormwater Sleuths Solve the Mystery of the Putrid Pipe" describes an IDDE investigation by the city's stormwater staff.

Seattle Public Utilities created this short and simple video to help businesses learn how to respond to small spills using a standard spill kit.

Kitsap County partnered with other West Sound jurisdictions to explore ways to better educate citizens to recognize spills and discharges that degrade water quality. The multi-jurisdictional team identified opportunities to promote the regional spills hotline and increase public awareness of stormwater pollution. This background research report documents outreach methods from around the country. A summary of findings from two area focus groups documents citizen awareness of the storm drain system and pollutants, and tests hotline messaging, graphic concepts, and outreach methods/products. Funded by an Ecology Grant of Regional or Statewide Significance.

Thurston County has partnered with the cities of Lacey, Olympia, and Tumwater to create an education program aimed at restaurant owners to eliminate improper disposal of grease/oil. Improper washing of hood filters and kitchen mats, improper cleaning of debris and dumpster maintenance and improper storage or disposal of kitchen grease/oil results in pollution being carried to storm water facilities, such as storm drains or ditches, and into bodies of water, such as streams, lakes. Inspectors provide one-on-one technical assistance visits and provide hood stickers and poster that targets best management practices (BMPs).
- Poster (PDF) (Publisher)
- Letter
- Hood sticker
- Talking points

Kitsap County Water Pollution Webpage NOTE: Kitsap County has offered to insert any jurisdiction’s contact number in its “Report Water Pollution” graphic. Please contact Callene Abernathy, cabernathy@co.kitsap.wa.us, for assistance. Users may also be able download the original drain graphic used by Kitsap County from their website.
Snohomish County field personnel training presentation and ‘knowledge quiz’
Contact Steve Britsch at Snohomish County if you are interested in PowerPoint versions of either document.
Snohomish County “Stormwater Pollution Found in Your Area!” doorhanger. Based on a publication from the EPA Nonpoint Source Outreach Toolbox.
Snohomish County IDDE Staff Training. Contact Arthur Lee (arthur.lee@snoco.org) at Snohomish County if you are interested in PowerPoint versions of this two-part training presentation.
- Ph. II IDDE Training Slides Part 1 of 2
- Ph. II IDDE Training Slides Part 2 of 2
Carpet cleaning fact sheet – developed by the Interagency Regulatory Analysis Committee (a consortium of city, county, and state government agencies in King County), this information and BMP guidance targets carpet cleaning businesses.
Mobile Carpet Cleaners guidance from Project Clean Water in the San Diego Region, includes “Do’s and Don’ts” and BMPS.
Resource Venture is the Seattle Public Utilities business education and assistance program with materials on best practices for a variety of small businesses.
Dry weather screening materials:
Bainbridge Island’s Water Resource Program prepared this IDDE Manual (April 2010) to direct all facets of the City’s Illicit Discharge Detection and Elimination Program. Topics covered include MS4 mapping, outfall inspections, conducting follow-up investigations, and corrective actions. Forms and equipment checklists are also included. With Bainbridge Island’s permission, four North King County jurisdictions collaborated to convert this manual into an IDDE Program Manual template that permittees may fill in to document their program(s).
Ecology prepared this spill kit checklist to support the work of the Local Source Control Program, which supports local government efforts in Puget Sound and Spokane with on-site technical assistance to businesses. This kit checklist will help create a kit that could be used to mop up small oil and grease spills. Other types of kits are designed for specific spill types – other chemicals, other viscosities, etc.
Seattle prepared this presentation about when and how to perform dye testing as a tool to identify illicit connections to the stormwater system.
City of Auburn Standard Operating Procedures (SOPs) in Word format (and forms) for dry weather screening activities:
This auto shop poster was created by Kitsap County with several statewide partners to educate auto shops across Washington State about BMPs for auto-related wastes. It is being piloted in three state regions and, if modified, will be updated here. The County recommends printing and laminating the poster professionally and sized 8” x 14”. There is a blank space at the lower left hand corner to insert your logo and contact information. Funded by an Ecology Grant of Regional or Statewide Significance.
Snohomish County and its partners in Kitsap County and the cities of Moses Lake, Wenatchee and Seattle, developed an education and outreach campaign (Dump Smart – It’s Not Just Water) for 3 mobile business sectors: carpet cleaners, painters and power/pressure washers. Find out how to run this mobile business education program in your jurisdiction in the Dump Smart – It’s Not Just Water, Stormwater Pollution Prevention for Mobile Businesses, June 2011 project report. Contact your Ecology regional permit specialist if you need the educational materials in a native file format and if you need window clings (a limited supply is available). Funded by an Ecology stormwater Grant of Regional or Statewide Significance.

IDDE Sample Regulations

King County
King County Code Chapter 9.12 Water Quality: Sections 4-7 (beginning on page 21) address requirements for local discharge prohibitions found under the Illicit Discharge Detection and Elimination (IDDE) special condition of both the Phase I and Phase II permits.

The City of Port Angeles adopted an ordinance to meet permit requirements to prohibit illicit discharges and connections. See Port Angeles Municipal Code sections 13.63.130 through 13.63.160.

The City of Puyallup’s draft ordinance to meet IDDE requirements for prohibiting illicit discharges.

The City of Snohomish adopted an ordinance to prohibit illicit discharges and connections.

The City of Burien developed a complaint response tracking form to record response actions.

The City of Longview passed an ordinance that prohibits illicit discharges and connections.

Additional examples/submittals are welcome and encouraged. Please work with your regional permit manager to add your SWMP program materials to this website.