Rain gardens: 

http://dcplanning.org

Storm waters usually caries pollution that mostly caused by motor vehicles and industrial activities. According to Water Resource Education (2009) Storm water carries metal, phosphorus, nitrogen, bacteria, pesticides and other kind of toxic. These materials that are harmful for nature reach to water sources with drains and make them polluted. One of the solutions to this issue is to use rain garden in urban green areas. Because storm water could not be absorbed from surfaces like parking, walk ways , drive ways roofs and other impervious surfaces it flows in drain system. But instead it could be easily absorb by depression gardens. Soil filters the water which plants in the garden absorb and flows to ground water and recharge it with less pollution (City of Des Monies 2009). These gardens could provide other advantages such as making the appearance of the city better and reducing the air and noise pollution. According to City of Desmond it is better to use native plants, because they have adjusted to that area and they need water in driest time of the year.


 Source:
-City of Des Monies Park and Recreation 2009,Rain Gardens, United State,accessed 18 May 2014,<http://clean-water.uwex.edu>
-University of Wisconsin Extension 2009,Polluted urban runoff, United State,accessed 18 May 2014 <http://www.dmgov.org>