The Minneapolis Park and Recreation Board (MPRB) has been monitoring stormwater since the late 1990s. Stormwater runoff from our streets, lawns, and buildings eventually flows into our lakes and creeks. We monitor stormwater flowing through storm sewer pipes and best management practices (BMPs) such stormwater ponds, grit-chambers, and other structures. We use automated samplers to collect samples for laboratory analysis.
Long-term stormwater management is one key to keeping lake water quality suitable for recreation and for sustaining plants and wildlife. MPRB is seeking dedicated funding to invest in stormwater management and protect Minneapolis lakes. More on this effort: Parkways and Stormwater: Investing, Protecting, and Restoring
Stormsewer Management
National Pollutant Discharge Elimination System (NPDES): The 1977 Clean Water Act gave the Environmental Protection Agency (EPA) the authority to implement pollution control programs for regulating discharges of pollutants into surface waters. With this authority, the EPA created the NPDES program. The EPA has delegated permitting authority for Minnesota’s program to the Minnesota Pollution Control Agency (MPCA).
The NPDES program mandates that operators of a Municipal Separate Stormsewer System have a NPDES permit. The MPCA issued the first NPDES Municipal Stormwater Discharge permit for Minneapolis on December 1, 2000. The permit requires Minneapolis to implement approved stormwater management activities. These activities are designed to mitigate the pollution effects of urbanization on stormwater runoff and create annual reports.
MPRB and Minneapolis Department of Public Works (MPW) are co-signers on the NPDES stormwater permit for Minneapolis. MPW and the MPRB have been joint permit holders since 2001. The purpose of stormwater monitoring is tounderstand how best management practices work. Understanding BMP function allows Minneapolis to set cleaning schedules, determine when to repair BMP’s, and change future designs to increase pollutant removal.
MPRB collects stormwater and snowmelt samples throughout the year at various locations in Minneapolis, as required by the NPDES permit.
Stormwater Ponds and Wetlands
Urbanization has led to drastic changes in the historical patterns of water movement. The implementation of stormsewers has created an effective system to quickly remove water from our streets. However, this also creates a streamlined pathway for pollutants and sediment to reach our waterbodies.
Stormwater BMPs such as treatment wetlands and ponds are being used throughout the park system to improve the water quality in our lakes and creeks. These structures help counteract the effects of urbanization by percolating stormwater through natural filters so that pollutants/sediment can settle out before reaching a water body.
MPRB has partnered in the construction of several stormwater treatment ponds and wetlands, including:
- Cedar Meadows Wetlands
- Standish-Ericsson Neighborhood Association (SENA) Wetland
- Lake Harriet Subsurface Flow Wetland
- Southwest Bde Maka Ska Wetlands
- Lake Nokomis Wetlands
More Information
View the MPRB Water Resources Report for detailed annual monitoring data, data collection methods, and more.
- 2022 Water Resources Report [PDF]
- 2021 Water Resources Report [PDF]
- 2020 Water Resources Report [PDF]
- 2019 Water Resources Report [PDF]
- 2018 Water Resources Report [PDF]
- 2017 Water Resources Report [PDF]