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We have a stormwater pond in our neighborhood that is part of a homeowners association, and I have a few questions. What is the recommended care for the water inside stormwater ponds, if any? What is the recommendation for vegetation around the pond? Are cattails okay? Can a fountain be put in the pond?
Stormwater ponds are a common feature of housing developments and other urban and suburban areas. They are part of the systems that municipalities use to control, and remove contaminants from, stormwater. Stormwater ponds may look like natural features of the landscape, and often have wetland vegetation and wildlife, but they should not be used for recreation!
Municipal stormwater carries rain and snowmelt into stormwater systems, bringing dirt, salt, trash, leaves, oil, and other pollutants with it. In stormwater ponds, some of those pollutants settle to the bottom so the water can flow on without them. The ponds have to be dredged periodically to continue functioning properly. Stormwater ponds also protect against flooding; large rainfalls can be released from them over days instead of hours, which relieves flooding downstream.
In general, the MPCA does not recommend treating the water with pesticides as it could be harmful to wildlife, and to water quality downstream. Learn more about stormwater ponds.
Check the requirements of your homeowners association and your local city, county, or township before altering any vegetation in or around a stormwater pond. Homeowners associations sometimes have maintenance agreements with their municipalities that include stipulations on vegetation.
The best plants for a pond depend on several factors including the type of pond and location. See our Plants for Stormwater Design manual to find the right plants for your pond. Cattails can be problematic for proper pond function if they are overabundant or in areas that could cause blockages, such as around a pond outlet.
Installing a fountain will also likely depend on local requirements. Your association or local government can tell you if it's allowed and any requirements for installation, operation, and maintenance. “If there are no local restrictions, fountains may provide benefits such as keeping algae away by aerating the water in the pond,” explains Cole Landgraf, a pollution control specialist in our municipal stormwater department. “However, they can be expensive to install and maintain and are not as effective for larger ponds.”
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