PRESS RELEASE from Cascadia Green Building Council

Cascadia Green Building Council releases groundbreaking report on the environmental impacts of wastewater treatment strategies.

Study finds that decentralized sewage treatment can reduce carbon emissions by as much as 44% compared to large-scale treatment systems.

SEATTLE — Oct.  18, 2011 — Capping two-and-a-half years of extensive water-related research, Cascadia Green Building Council released today Clean Water, Healthy Sound, a groundbreaking report that uses Life Cycle Analysis (LCA) to examine and compare wastewater management practices in urban areas.

Using a mid-sized city in the Puget Sound region as a case study, Cascadia, measured a broad spectrum of environmental impacts associated with large scale, centralized sewage conveyance and treatment systems and compared them against smaller, decentralized alternatives.

The study identifies a direct relationship between low-density urban and suburban neighborhoods and substantial global warming impacts from pumping sewage across long distances.  Decentralized techniques have the potential to dramatically reduce or even eliminate these negative effects by decreasing the energy required to pump and treat wastewater. Some of the decentralized techniques analyzed (notably constructed treatment wetlands and composting toilets) also promise a major reduction in other life cycle environmental impacts such as emissions associated with acid rain, smog and air particulates. 

“The ‘Clean Water, Healthy Sound’ report represents a major milestone for the green building/green infrastructure community,” says Katie Spataro, Cascadia’s Research Director. “Countless municipalities across North America are preparing to make massive investments in their wastewater infrastructure. This report allows us to make a clear and scientifically rigorous case for encouraging cities to explore decentralized and distributed strategies.”

This study, made possible by a grant from the Russell Family Foundation, rounds out several years of research by Cascadia around best practices for water supply and treatment. Earlier this year, Cascadia partnered with the City of Seattle to identify regulatory pathways for projects seeking to implement onsite water systems.  Cascadia also recently released a policy guide designed to help regulatory officials and elected representatives make informed decisions as they consider upgrades and expansions to existing infrastructure. Much of Cascadia’s focus has been on the Puget Sound region, but the LCA study and policy guide are relevant for communities nationwide.

“It’s our hope that this study, combined with our extensive outreach and advocacy efforts, will spur a broad movement toward more ecologically sound water practices and policies,” notes Jason F. McLennan, Cascadia’s CEO. “Greater support for smaller-scale, decentralized systems is crucial if we are serious about addressing the negative impacts related to how we manage water and waste. ”

All of Cascadia’s recent reports are available for download here.

About Cascadia Green Building Council:

Founded in 1999, Cascadia is a proud chapter of both the US and Canada Green Building Councils and serves the green building community in Oregon, Washington, British Columbia and Alaska. Cascadia promotes LEED and the Living Building Challenge through a comprehensive program of education, outreach, advocacy and research. A network of fourteen branches located in each of the region’s population centers ensures that Cascadia’s programming is targeted and locally relevant. Cascadia is an affiliate of the International Living Future Institute, which is also home to the Living Building Challenge, The Natural Step Network, USA and Ecotone publishing. Please visit

For more information, please contact:

Katie Spataro, Cascadia Green Building Council,, 206-223-2028