Rein in Runoff with Rain Garden

By TIM FAULKNER/ecoRI News staff

The concept is simple: Keep rain and the pollutants it carries out of storm drains with a rain garden.

Creating a rain garden is actually quite easy, according to Kate Venturini, an instructor with the the University of Rhode Island's Stormwater Solutions Project.

A rain garden is a shallow-planted area designed to soak up runoff from roofs, driveways, lawns and parking lots. During heavy rains in particular, these planted gardens reduce the stream of water — and the harmful pollutants it collects — from flowing down streets and into local waterways.

Currently, about 12 percent of Rhode Island is covered by impervious surfaces such as asphalt, cement and roofing.

These gardens allow concentrations of nitrogen and phosphorous to absorb and dissipate in soil instead of harming aquatic ecosystems and contaminating drinking water supplies. Other common pollutants washed down street drains include nitrogen oxide from car exhaust, rubber particles from tires, metal from wearing brakes, spilled antifreeze and lawn fertilizer.

The volume of runoff from even a small area can be huge. A 1,000-square-foot roof produces about 600 gallons of water from an inch of rain, Venturini said.

Ways to reduce runoff and recycle water at home include:

Rain barrels are perfect for capturing rain water and then using that water on your gardens. It saves water and lowers your water bill.

Grid pavers and other porous materials are great alternatives to asphalt and cement driveways and patios.

Downspout extenders help divert rain to a landscaped area or garden and away from paved areas and even open lawn, which are not the best spots to catch runoff from a downspout.