What is a Raingarden?

Raingardens are growing in popularity as an attractive, low-maintenance landscape alternative that helps protect and restore water quality. They are designed and planted to capture rain water so it can penetrate into the soil. This reduces the stormwater runoff that takes pollutants from the air, yards and streets and carries them into lakes, rivers and wetlands. A raingarden is a way for homeowners or business owners to reduce the effects of polluted stormwater runoff simply by planting a specialized garden designed to capture redirected runoff water and allow it to slowly drain into the ground and recharge our underground aquifers with filtered, cleaner water. Raingardens are also a way to beautify property with perennial plants that require little maintenance, thrive without fertilizer or pesticide, and enhance the value and attractiveness of your neighborhood and community.

Raingardens are an infiltration technique - water is captured in a garden shaped like a basin that uses native plants. Native plants are beautiful, colorful, highly adapted plants that have grown in Minnesota for thousands of years, that adapted to our long winters and varying water flows by developing long and thick root systems and special leaf structures that are well-suited to drawing water deep into the underground. The native plant roots and the empty channels left by last year's roots give the water the "pipes" to re-enter the ground rather than run off into the storm sewer. This ground-filtering process helps clean our precious resource - our water.

What causes rain water pollution?

There are two general categories of pollution: pollution that comes from a direct or a known source and pollution that comes from indirect contaminant sources. Direct sources like factories or waste treatment plants emit contaminated fluids directly into water supplies. In the United States and other countries, these practices are regulated, but this doesn't mean that pollutants can't be found in our waters.

Indirect sources (or non-point source pollution) enter our water supply from soils and groundwater that contain the residue of fertilizers or pesticides, and improperly disposed industrial wastes. Pollution in our rain water comes from atmospheric contaminants from human practices like the gaseous carbon emissions from our cars and trucks, and industrial air emissions from facilities like coal plants, for example. This air pollution is gathered in rain water as it falls.  It is this polluted water that flows off our roofs, lawns and sidewalks carrying residue of fertilizer, pesticide, pet waste, gas and oil into the city storm sewer, that ultimately pollutes our lakes, rivers, and streams. This is the problem rain gardens help solve: raingardening is a cost-effective and beautiful way to reduce the effects of this "nonpoint source pollution" in our watersheds, and to beautify our city and neighborhoods.