Portland – Grey to Green Initiative

Rosen relates that after seeing the Watershed Management Plan, Adams started asking questions like “How long is it going to take to implement?” and “What money do you have?” Upon hearing the answers, Adams decided that more support was needed to kick start the work, and the Grey to Green initiative was born.

Implemented in 2008, BES’ Grey to Green initiative will invest $55 million — funded directly from stormwater fees paid by city residents, as well as capital funds — over five years “to make stormwater management more sustainable, restore watershed health and enhance Portland’s livability,” according to an April 2009 update report.[1] It would do so through a series of seven activities: land acquisition, ecoroofs, revegetation, culvert replacement, green streets, trees and invasive plant removal.

Ecoroof in Portland

Ecoroof in Portland. Credit: City of Portland, Oregon Bureau of Environmental Services

As its name implies, Grey to Green aims to use green infrastructure activities to support needed city functions, a cultural shift away from traditional gray infrastructure. Says Rosen, “A significant part of the work we do is managing stormwater or rainfall, and the shift has been to treat it as more of a resource rather than a waste and trying to mimic natural systems where rain falls versus moving it into a pipe and sending it speeding into the river or to a wastewater treatment plant for expensive processing.”

Each of the seven main activities of Grey to Green addresses concerns about stormwater management. Land acquisition allows important natural areas affecting the region’s streams to be protected from future development, while removal of invasives and revegetation ensure natural areas are flourishing. Culvert replacements reduce flooding and erosion concerns, while also improving the streams to better accommodate fish and other wildlife. Ecoroofs and green streets are aimed at controlling the stormwater within the city limits. Trees, though, bridge the gaps between many of these activities, and more entities than just the city of Portland are taking notice.

In Washington County, Oregon — part of the Portland metro area — Clean Water Services is doing innovative green infrastructure work. One of the utility’s water treatment plants has been releasing treated water that is too hot according to guidelines set forth in the Environmental Protection Agency’s Clean Water Act. If the utility were to use gray infrastructure in the form of a “chiller” plant for the water, it would cost $50 million to build and implement. Instead, Clean Water Services received permission from the EPA to plant two million trees along the rivers and streams leading into the existing plant. By shading these waterways, the water’s entry temperatures will be reduced, which will mean the treated water’s temperature will be lower — saving the utility tens of millions of dollars, while also providing the region with the ancillary benefits a strong tree canopy provides.

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[1] Portland Bureau of Environmental Services. Grey to Green Update April 2009. http://www.portlandonline.com/bes/index.cfm?c=53256&a=312546 (accessed Sept. 4, 2012).