Clean Water Act

The Clean Water Act (CWA) was introduced in 1972 to help establish structure for regulating pollutant discharges into the water of the United States. This also introduced the National Pollutant Discharge Elimination System (NPDES) which prohibits discharges of pollutants from any point source into the nation’s waters except as allowed by the NPDES permit. Phase I was issued in 1990 for large storm sewer systems and Phase II for smaller communities was signed in October of 1999. The City of Winona operates under the Phase II of the NPDES MS4 General Permit.

Municipal Separate Storm Sewer System

The City’s Municipal Separate Storm Sewer System (MS4) comprised of inlets, outlets, storm pipes, ponds, and other storm sewer structures that help convey stormwater throughout the City while reducing the amount of sediment and pollution that is collected before it exits the City and outfalls into various bodies of water nearby.


The City of Winona is required to follow the Minnesota Pollution Control Agency’s (MPCA) NPDES MS4 General Permit, which is intended to reduce the amount of sediment and pollution that enters surface and ground water from storm sewer systems to the maximum extent practicable. As a part of the MS4 General Permit, the City is required to develop a Stormwater Pollution Prevention Program (SWPPP) that incorporates Best Management Practices (BMPs) applicable to its MS4.

Storm Sewer Utility Fee

Beginning January 1, 2003, a storm sewer utility was created by ordinance and a fee has been collected along with the quarterly billing for the water and sanitary sewer utilities. The purpose of the fee is to pay for increased treatment monitoring and education related to storm water runoff, as required by the Environmental Protection Agency (EPA) Federal regulations. Fees collected will also be used for regular maintenance of the existing storm water collection system.

The Storm Sewer Utility fee is based on the size and zoned usage of the property. Theoretically, a large property or a property with a significant impervious surface will generate more rainwater runoff than one that is smaller or less developed. The factors used to calculate the fee take this into consideration.