How Green Infrastructure Measures Up to Structural Stormwater Services
Trees Slow Runoff, Improve Water Quality
“Whether tree canopy across the country is declining due to fire, development, or other reasons, the resulting cleared or urban landcover produces much more stormwater runoff than the natural landscape,” writes Cheryl Kellin in the July/August 2006 issue of Stormwater Magazine.
“The Natural Resources Conservation Service, historically, and the Center for Watershed Protection, more recently, have deemed forest cover to be the best use of land for water storage, recharge, runoff reduction, pollutant reduction, and habitat.”
An Indicator of Watershed Health
“Tom Schueler, director of watershed research and practice for the center, sees percent forest cover—rather than impervious surface—as a leading indicator of watershed health.”
“Trees and soils function together to reduce stormwater runoff. Trees reduce stormwater flow by intercepting rainwater on leaves, branches, and trunks.”
“Tree cover helps intercept rainwater, thus reducing the amount and speed of stormwater as it filters pollutants that eventually flow to receiving waters.”
Financial Impact
According to Cheryl Kellin, studies show that impervious surfaces in urban areas in the United States have increased by 20% over the past two decades at a cost exceeding $100 billion nationally. Thus, local governments are increasingly looking toward non-built rainwater management strategies, including trees, to reduce the cost of constructing stormwater control infrastructure.
Decision Making
“Obtaining reliable calculations of increased stormwater volumes and water quality as landcover becomes more urbanized is an important environmental and economic issue––but one that is poorly understood by decision makers,” states Cheryl Kellin.
To read the complete story, click on How Green Infrastructure Measures Up to Structural Stormwater Services.
Acknowledgement:
Before STORMWATER, The Journal for Surface Water Quality Professionals, there was no single publication written specifically for the professional involved with surface water quality issues, protection, projects, and programs.
Posted January 2010