City of Mercer Island, Washington - Home City of Mercer Island, Washington - Home Facebook Twitter YouTube
site map
Back to Public Works

Service Request
Sanitary Sewer Utility
Stormwater Utility
Report a Spill
Mercer Island and Lake Washington Water Quality
West Nile Virus
Stormwater Permits
Help Reduce Stormwater Runoff Pollution
Water Utility
City Projects
Emergency Well
Recycling & Solid Waste
Roadway, Trails & Rights-of-Way
Parking, Traffic, Pedestrians, Bicycles
Small Works Roster and Consultant Roster
Snow and Ice Response Plan
Meet the Public Works Director

City Code
RFPs & Bids
Staff Directory

9601 SE 36th Street
Mercer Island, WA 98040
Phone: 206.275.7608
Fax: 206.275.7814
Email: publicworks@mercer. . .
Hours: 7:30 AM - 4:00 PM (Mon-Fri)
Notify me by Email
Report a Spill

The City of Mercer Island asks residents and businesses to help us keep our water clean. If you see spills or illegal discharges into a city stormwater drain, call the City’s Maintenance Department at (206) 275-7608 during regular business hours (8:00 am to 5:00 pm), or (425) 577-5656 after hours.


Examples of illegal discharges or spills include:

§         Used motor oil, fuel oil, gas, anti-freeze or other automotive fluids

§         Fertilizers or other landscape chemicals

§         Paint and solvents

§         Discharge from swimming pools or other highly chlorinated water

§         Sewage and industrial wastewater


When we receive a call on the hotline, a city crew will respond to the site, assess the situation and take appropriate action. Left untreated, spills or discharges could flow through our stormwater system and into Lake Washington, so we appreciate your prompt attention and report.

The City of Mercer Island’s stormwater permit from the Washington Department of Ecology requires that we publicize information about our
Illicit Discharge and Elimination (IDE) hotline.


Illicit Discharge Detection and Elimination (IDDE) Program 


The National Pollutant Discharge Elimination System (NPDES) regulates the discharge of stormwater under the authority of the Federal Clean Water Act. Washington State Department of Ecology (Ecology) has the designated authority to administer NPDES within the state of Washington. Under this authority, Ecology has issued NPDES permits regulating the discharge of stormwater.


The City of Mercer Island is under the regulation of the Phase II Municipal Stormwater Permit issued on February 16, 2007. The current Phase II permit will remain in effect until February 15, 2012, after which a new Phase II permit will be issued. The Phase II permit mandates permittees to prepare and implement an Illicit Discharge Detection and Elimination (IDDE) program. The City's IDDE plan and its implementation satisfies this requirement.




Download File
IDDE Program - FinalCOPY.pdf


Get Acrobat Reader The above document(s) are Adobe® Acrobat® PDF files and may be viewed using the free Adobe® Acrobat® Reader™. Most newer web browsers already contain the Adobe® Acrobat® Reader™ plug-in. However, if you need it, click on the "Get Acrobat® Reader™" icon to download it now.

City of Mercer Island Washington | All Rights Reserved © 2019| Privacy Policy | printer friendly version Printer friendly version | Site Handcrafted in Ashland, Oregon by Project A