Rain gardens

I found out about this really cool concept of Rain Gardens.

"A rain garden resembles a regular perennial garden in many ways. It is designed with deep-rooted plants that come back year after year; it is pretty to look at; it often has lovely flowers, grasses, trees and shrubs. So what makes it different from any other perennial garden? here are certain qualities that make a rain garden unique.

• Rain Gardens have a ponding area, but they are not ponds. They often are planted with wetland plants, but they are not wetlands (although you can design a rain garden that mimics a wetland).
• The garden absorbs and filters rain that would otherwise run off your property and down the storm drain. This stormwater runoff usually comes from an impervious surface that rain cannot soak into, such as a roof or parking lot, or even a lawn.
• Many of the plants in the garden are native to the region, and have extensive deep roots that help the garden absorb rain. The native plants do not need special attention once they are established.
• There is a bowl-shaped dip in the garden, which holds the rain while it soaks into the soil.
• The garden bed is prepared or sometimes replaced to a depth of two feet in order to de-compact the soils and make the garden able to absorb water."

One of the main benifits us it reduces pollution. As the American Chemical Society states:

"If properly designed "rain gardens can effectively trap and retain up to 99 percent of common pollutants in urban storm runoff, potentially improving water quality and promoting the conversion of some pollutants into less harmful compounds, according to new research scheduled for publication in the Feb. 15 issue of the American Chemical Society journal, Environmental Science and Technology. The affordable, easy-to-design gardens could help solve one of the nation’s most pressing pollution problems, according to the study’s authors, Michael Dietz and John Clausen of the University of Connecticut. "

There are other benefits to Rain Gradens too which are mentioned here.