Moving Beyond Gray vs. Green to Embrace “Sustainable Infrastructure”


A bioretention pond slowly releases stormwater runoff into an enlarged storm sewer.  An overflow drain system collects sheet flow from a bioswale to manage storms larger than the design event.  These are both examples of how green infrastructure utilizes and integrates traditional “gray” components, like conduits and drains, to function properly and efficiently.  On a much larger scale, cities around the country must rely on the right mix of technology and infrastructure solutions to address wet weather and manage stormwater runoff in urban and suburban areas.  “Sustainable infrastructure” solutions balance traditional gray infrastructure with appropriate green elements to improve the quality of urban waters, and enhance the livable environment for residents.

The clean water community is moving beyond the “gray” versus “green” mentality. One is not inherently better than the other – in fact, they are inextricably linked, as the examples above illustrate. The communities that have already realized this are focusing less on labeling wet weather control systems as gray or green and instead are embracing a cost-effective hybrid solution that allows them to best address water quality concerns. NACWA is committed to “sustainable infrastructure” as the appropriate balance of these water quality solutions.

Green infrastructure literally brings the stormwater challenges to the surface.  It has aesthetic, air quality, and hydrologic benefits, all while providing a valuable opportunity to educate the public on how utilities manage stormwater.  However, there are no completely “green” solutions.  In a developed area, engineered solutions will be necessary to get water from Point A to Point B.  Large conduits and storage can convey millions of gallons of stormwater runoff from flood-prone areas, to treatment or waterways – in a magnitude that decentralized green infrastructure simply cannot.  Hybrid solutions, where gray and green are working together, are not only more robust, they are the true definition of “sustainable infrastructure”.

Utility managers are now quantifying the social, economic and environmental benefits to their community when planning water system improvements. Public understanding and education have become critical for utilities seeking to gain acceptance for major clean water infrastructure projects. Pursuing a “sustainable infrastructure” approach provides utilities with the opportunity to educate the public on the role they play in improving water quality through the integration of visible elements like rain gardens, green roofs, and permeable pavement with the gray elements that often go sight-unseen. “Sustainable infrastructure” provides the best combination of solutions for utilities to maximize the social, environmental and economic benefits.

“Sustainable infrastructure” is the future of managing wet weather and addressing resiliency challenges cost effectively in cities around the country, in a way that truly improves the quality of life for residents. As regulatory obligations multiply, NACWA is committed to ensuring utilities are responsibly using “sustainable infrastructure” and that this approach receives the appropriate support.

This entry was posted in Clean Water, CSOs/SSOs, Green Infrastructure, Infrastructure, Stormwater, Utility Management, Utility of the Future and tagged , , , , , , . Bookmark the permalink.

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