

Illicit discharges are the introduction of non-stormwater runoff, sewage, or hazardous materials into the public stormwater system. Studies have shown that pollutant discharge from stormwater systems in dry weather due to illicit discharges can exceed the total pollutant flow from storm event flows. Stormwater systems typically flow untreated to water bodies thus Ecology places a significant emphasis on illicit discharge detection to protect water quality.
Illicit Discharges are: septic or sewer connections, liquid or solid wastes, operational wash water, hazardous waste.
With certain conditions, the following are not Illicit Discharges: water line or hydrant flush water, lawn water, swimming pool discharge, street/sidewalk wash water, dust control water, or permitted discharges covered under another permit.
Illicit Discharges are not: ground water, foundation drains, air conditioning condensate, irrigation water from agricultural sources, crawl space pump discharge, footing drains.
“An ordinance prohibiting illicit discharges has been adopted by the regional co-permittees in accordance with permit requirements. The following table links the ordinances to the specific jurisdictions:
Yakima County Ordinance 4-2009
City of Yakima Ordinance 2009-39
City of Yakima Ordinance 2009-39 Amendment
City of Sunnyside Ordinance 2009-17
City of Union Gap Ordinance 2624
Regional co-permittees are required to develop and implement an ongoing program to detect and address non-stormwater discharges to the stormwater system including spills, illicit connections, and illegal dumping by August 19, 2011. The Illicit Discharge Detection and Elimination Procedures document provides the regional co-permittees with guidance to implement this program.
To report a suspected illicit discharge in Sunnyside, Union Gap, Yakima, or Yakima County, call: (509) 574-2300 or e-mail PublicServicesIllicitDischarge@co.yakima.wa.us.