Reporting spills & eliminating illicit discharges

Identifying and reporting spills, illicit discharges, and unauthorized connections that might affect the stormwater drainage system helps keep pollutants out of receiving waterbodies. Washington State Department of Transportation (WSDOT) does not allow the discharge of anything other than stormwater into our stormwater drainage system, nor do we allow any pipe, ditch, or other manmade structure to connect to our stormwater drainage system without authorization.


Reporting Procedures

Report spills and illicit discharges that are not comprised entirely of stormwater on or along state highways or WSDOT properties, as well as connections to our stormwater drainage system, to the appropriate authorities listed below.


Emergency or hazardous spills

Call 911 for spills on state highways or WSDOT properties that may impact the safety of the traveling public or the environment. These could include spills related to vehicle collisions, fires, unknown chemicals, or explosive hazards. See our Hazardous materials during construction webpage for additional information.


Non-emergency spills and illicit discharges that could reach WSDOT’s stormwater drainage system

Call the closest Department of Ecology office.

  • Central Washington: (509) 575 -2490
    Counties: Benton, Chelan, Douglas, Kittitas, Klickitat, Okanogan, and Yakima
  • Eastern Washington: (509) 329-3400
    Counties: Adams, Asotin, Columbia, Ferry, Franklin, Garfield, Grant, Lincoln, Pend Oreille, Spokane, Stevens, Walla Walla, and Whitman
  • Northwest Washington: (425) 649-7000
    Counties: Island, King, Kitsap, San Juan, Skagit, Snohomish, and Whatcom
  • Southwest Washington: (360) 407-6300
    Counties: Clallam, Clark, Cowlitz, Grays Harbor, Jefferson, Mason, Lewis, Pacific, Pierce, Skamania, Thurston, and Wahkiakum


Illicit connections or non-emergency spills and illicit discharges that do not reach WSDOT’s stormwater drainage system

Call the WSDOT Region Illicit Discharge Detection and Elimination (IDDE) contact. Contacts are available during normal business hours only. Leave a message if contacting outside of business hours.

WSDOT Regions and illicit discharge detection and elimination contacts map


How to identify illicit discharges, connections, and spills

Use the definitions, warning signs, and examples below to help determine if you have identified an issue that needs to be reported. Keep this information in mind and be on the lookout for issues to report.


Use these explanations to determine if you have identified an issue to report, and how to categorize it.

  • Illicit discharge – any discharge to WSDOT property or stormwater drainage system that is not comprised entirely of stormwater.
  • Illicit connection – any unauthorized pipe, ditch, or other manmade structure that is physically connected to WSDOT’s property or stormwater drainage system.
  • Spill – unintentional release of a non-stormwater substance to WSDOT's stormwater drainage system or property related to a single event. Spills often occur in emergency situations, such as a collision causing oil or other automotive fluids to spill onto the highway surface.

Indications and warning signs

If you see any of these potential issues, you may need to report them following the procedures on this page:

  • Staining
  • Residues
  • Oily substances
  • Odors
  • Abnormal flow during dry weather
  • Turbid (murky) water
  • Suds