Urban Storm Water Program (MS4)

On March 6, 2015 Washington County was issued a Wisconsin Pollution Discharge Elimination System (WPDES) Municipal Separate Storm Sewer Systems (MS4) Permit requiring the county to implement a storm water management program and control measures to improve urban water quality.

The MS4 permit required the county to develop a Storm Water Management Program that includes the following components, and much more.

Public Education and Outreach
To encourage the public and businesses to modify their behaviors and procedures to reduce storm water pollution.

Public Involvement and Participation
To encourage and allow for participation from individuals to prevent storm water pollution.

Illicit Discharge, Detection and Elimination
Develop a program to identify, prevent, and eliminate illicit discharges to storm sewer systems.

Construction Site Pollutant Control
Adopt/update a soil erosion control ordinance and enforce it on construction sites.

Post-Construction Site Stormwater Management
Develop/update a post-construction ordinance and enforce it to ensure that areas of new and redevelopment will include structural measures to control pollutants, control peak flow, maintain infiltration, and establish vegetated protective areas adjacent to waterways and wetlands.

Pollution Prevention
Implement and maintain practices to prevent pollutants from municipally-owned transportation infrastructure, maintenance areas, storage yards, sand and salt storage areas, and waste transfer stations from entering the storm sewer system.

Stormwater Quality Management - To reduce pollutants, reduce the Total Suspended Solids (TSS) and Total Phosphorus (TP) carried in storm water from existing urban areas as compared to no controls; achieve compliance with DNR approved TMDLs.

Storm Sewer System Mapping - Develop and maintain a map of the storm sewer system; identifying storm sewer conveyances such as pipes and ditches, and also identify roads, streams and lakes (including 303d waters).

Impaired Waters – Where the storm sewer system discharges a pollutant of concern to an impaired water, a plan shall be developed to reduce those pollutants.

Annual Report
An annual report on the status of permit requirements and a fiscal analysis on annual expenditures and proposed budget for program activities.

Background
Urban storm water runoff contains pollutants from roads, parking lots, construction sites, industrial storage yards and lawns. In 1987 Congress amended the federal Clean Water Act to control storm water pollution. Federal regulations thus required owners of storm water pollution sources, including many industries, municipalities and construction sites, to have National Pollutant Discharge Elimination System (NPDES) Stormwater Permits.

At the State level and to meet the requirements of the federal Clean Water Act, DNR developed the Wisconsin Pollutant Discharge Elimination System (WPDES) Storm Water Discharge Permit Program which is administered under the authority of ch. NR 216, Wis. Adm. Code.

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.

Questions on the County's MS4 Program or to report an illicit discharge may be directed to Katie Wilson at 262-208-8076 or [email protected].

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].