Cities of all sizes are tackling their water pollution problems, such as stormwater runoff and sewage overflow, by using green infrastructure and design, and they will save money as a result, according to a peer-reviewed report from the Natural Resources Defense Council. The report provides case studies on 14 cities using these methods and encourages the U.S. EPA to advance these solutions nationwide.
“Every single day, millions of gallons of good water needlessly drain away, filling our waterways with sewage and urban pollutants, rather than replenishing our water supply,” said NRDC water program director David Beckman. “But it doesn’t have to be that way. By making our communities literally greener, we can make our water sources cleaner too – and with much greater return than conventional solutions.”
Rooftops to Rivers II details common water pollution problems and provides case studies on remedies from 14 geographically diverse cities. The cities featured have effectively managed stormwater and reduced runoff pollution while saving money and beautifying their cityscapes by capturing rain where it falls.
The cities featured are ranked on a six-point Emerald City Scale and are listed below from the highest to lowest points scored:
- Philadelphia (6)
- Milwaukee (5)
- New York (5)
- Portland, Ore. (5)
- Syracuse (5)
- Washington, D.C. (5)
- Aurora, Ill. (4)
- Toronto (4)
- Chicago (3)
- Kansas City, Mo. (3)
- Nashville (3)
- Seattle (3)
- Pittsburgh (1)
- Detroit Metro Area and the Rouge River Watershed (1)
The six-point scale identifies the primary actions every city can undertake to maximize green infrastructure: a long term green infrastructure plan, a retention standard, a requirement to reduce existing impervious surfaces using green infrastructure, incentives for private-party action, guidance or other assistance in deploying green infrastructure, and a dedicated funding source. Only Philadelphia is undertaking all six actions.
Green infrastructure stops runoff pollution from the start by capturing rainwater and storing it or letting it filter back into the ground. Examples include green roofs, street trees, increased green space, rain barrels, rain gardens, and permeable pavement. These methods also help beautify neighborhoods, cool and cleanse the air, lower heating and cooling energy costs, boost economies, and support American jobs.
The report details how green infrastructure is often more cost-effective than traditional approaches to addressing runoff. Philadelphia estimates that a traditional approach to its sewage overflow problems would have cost billions more than its state-approved green infrastructure plan.
As the EPA prepares to update its national standards for controlling runoff pollution, these cities’ successes should encourage the agency to adopt requirements that will drive similar approaches nationwide, according to the NRDC. The complete NRDC report is available at nrdc.org/rooftops.
