With a change in ordinance to allow for higher density affordable housing, Bellingham opened the way for their largest pervious concrete pour to date. In the new development of Mathei Place, there were no existing stormdrains. Even with the well-draining soil in the area, careful considerations where taken for the pervious concrete installation, from a finer reservoir course to specially constructed overflow drains.
Such considerations where not needed at the downtown core, where existing stormdrains were used in conjunction with repurposed right-of-ways for the construction of biorentention cells. Local businesses were encouraged to participate and maintain their little roadside gardens, with those who have signed a pledge having bronze plaques installed in front of their shops.
Picturesque Lake Whatcom serves as a source of drinking water for Bellingham. When a developer extended a road to access to four lots, they installed a river rock spillway that feeds into a bioretention cell. The primarily native plantings are maintained by the city and adjacent landowners.
Farther south, in Seattle’s Venema area, large cascading bioretention cells were used. They stepped down the steep grade of the road, taking in all of the stormwater generated by Venema and surrounding roads.