Rain gardens are strategically designed and highly efficient gardens that catch stormwater runoff from an impervious surface, such as the roof of your home or garage, and filter it into the ground instead of allowing it to run into a storm drain. When properly constructed, they can collect 90-100% of the runoff from a roof.
Typical rain gardens are sized between 100 and 300 square feet, are 4"-8" deep with a flat bottom, are edged by an low mound of earth (also known as a berm), and contain plants with deep root systems such as wild flowers and native grasses. For the easiest construction, they should be located on lawns with slopes less than 12%.
Although they are not meant to replace the Village's storm sewer system, rain gardens can greatly enhance our system and empower you as a homeowner to lessen your environmental footprint. When even small rain gardens are installed throughout a neighborhood, they can have a great impact on our local ecology and storm conditions.
According to the University of Wisconsin-Extension, rain gardens typically allow 30% more water to soak into the ground than a conventional turf lawn, which helps replenish local and regional aquifers, helps protect the community from flooding, improves local drainage issues, protects streams and lakes from pollutants, and provides valuable habitats for birds, butterflies, and beneficial insects.