Stormwater discharges are regulated through National Pollution Discharge Elimination System (NPDES) permits. Through this permit, Chanhassen, as an owner/operator of a storm sewer system must develop a stormwater pollution prevention program (SWPPP) that uses a variety of best management practices (BMPs) to achieve this goal
The City’s MS4 (Municipal Separate Storm Sewer System) permit is designed to reduce the amount of sediment and other pollutant that enter state waters from the City’s storm sewer network. City staff is required to submit annual MS4 reports to the Minnesota Pollution Control Agency. See below for the report submitted for the year 2020.