University of Connecticut scientists say properly designed "rain gardens" can trap and retain up to 99 percent of common pollutants in urban storm runoff.
The researchers said the affordable and easy-to-design gardens could potentially improve water quality and promote the conversion of some pollutants into less harmful compounds.
Study authors Michael Dietz and John Clausen say more than half of the rainwater that falls on a typical city block will leave as runoff that includes metals, oils, fertilizers and other particulate matter.
Dietz and Clausen say rain gardens -- shallow depressions in the earth landscaped with hardy shrubs and plants and surrounded by bark mulch -- offer a simple remedy to the problem.
In a two-year study of roof-water runoff, the researchers found rain gardens significantly reduced concentrations of nitrates, ammonias, phosphorous and other pollutants reaching storm drains. In addition, design tweaks permitted bacteria in the soil to convert harmful nitrates into nitrogen gas, preventing them from entering the groundwater.
The research is to be detailed in the Feb. 15 issue of the American Chemical Society journal, Environmental Science and Technology.
Copyright 2006 by United Press International
Related stories:
If a street tree falls... what does it take to make sound policy?
There's little debate that, when a tree falls near a city street, it makes a sound. But other questions are more difficult to answer: Who is affected by the falling tree and how? Who is liable for the damage? And who is responsible for deciding how to replace the tree?
Keep It Growing -- Plant Fall and Winter Vegetables in July
(PhysOrg.com) -- In mild parts of western Oregon and along most of the coast, it is possible to grow a succession of garden vegetables throughout the year. You can extend the season well into fall in many parts of the Pacific Northwest with a little knowledge and protection of your plants from the elements.
Backyard gardens need good food-safety practices, too
The recent tomato contamination outbreak has many people thinking about growing their own garden-fresh fruits and vegetables. But a food-safety specialist in Penn State's College of Agricultural Sciences says it's not where the produce is grown, but how it's grown, so amateur cultivators should know a few important tips about home-garden food safety.
Common herbicide disrupts human hormone activity in cell studies
A common weedkiller in the U.S., already suspected of causing sexual abnormalities in frogs and fish, has now been found to alter hormonal signaling in human cells, scientists from the University of California San Francisco (UCSF) report.
Dwarf cloud rat rediscovered after 112 years
A team of Filipino and American scientists have rediscovered a highly distinctive mammal -- a greater dwarf cloud rat -- that was last seen 112 years ago. Furthermore, it has never before been discovered in its natural habitat and was thought by some to be extinct.
Recycled garden compost reduces phosphorus in soils
Broccoli, eggplant, cabbage and capsicum grown with compost made from recycled garden offcuts have produced equivalent yields to those cultivated by conventional farm practice, but without the subsequent build up of phosphorus.
Corals reveal impact of land use
Using the corals on the Great Barrier Reef (GBR) as a history book, researchers have linked land use along the coast to decades of declining water quality and poor coral health.
Butterfly Wings Are Templates for Photonic Structures
By replicating the complex micron- and nanometer-scale photonic structures that help give butterfly wings their color, researchers have demonstrated a new technique that uses biotemplates for fabricating nanoscale structures that could serve as optical waveguides, optical splitters and other building blocks of photonic integrated circuits.