Storm Water Management Program

Washington County’s Storm Water Management Program-(SWMP) (pdf) is intended to be a living document on how the county will meet its requirements of Wisconsin Administrative Rule NR 216 and its WPDES-MS4 permit. This plan establishes activities and programs, and provides a schedule for implementation that aligns with the compliance and implementation schedule of the MS4 Permit.

Washington County's SWMP highlights the following permit compliance requirements and activities (pdfs):
Public Education & Outreach
Public Involvement & Participation
Illicit Discharge Detection & Elimination
Construction Site Pollution Control
Post-Construction Storm Water Management
Pollution Prevention
Storm Water Quality Management
Storm Sewer System Maps


Supplements to Pollution Prevention (pdfs):
Supplement 1 Supplement 2

A municipal separate storm sewer system or MS4 means a conveyance or system of conveyances including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, constructed channels or storm drains, which meet the following criteria: 1) owned or operated by a municipality, 2) designed or used for collecting or conveying storm water, 3) is not a combined sewer conveying both sanitary and storm water, and 4) is not part of a publicly owned wastewater treatment works that provides secondary or more stringent treatment.

Countywide Map (large pdf)
Storm Sewer Systems
An important aspect of a Storm Water Management Program is identifying where stormwater enters surface waters, these are referred as MS4 Outfalls, the following map identifies specific know outfalls and drainage area associated with County Highways.
Outfall Maps (pdf)

Annual Reports (pdfs)
2016 2017 2018 2019 2020 2021

Questions on the County's MS4 Program or to report an illicit discharge may be directed to Paul Sebo @ (262) 335.4805 or [email protected].