Forget potholes—the streets of Bellingham, Wash., are filled with potties. Well, OK, maybe not the streets, but a multi-use path, part of the Meador-Kansas-Ellis Trail project between Meador Avenue and Ellis Street. And that project was recently honored with the first official Greenroads certification for its innovative use of porcelain from recycled toilets, among other ultra-green measures.
Here’s how it came about: When city project engineer Freeman Anthony got wind that a local nonprofit was replacing hundreds of toilets, he called up his regular ready-mix concrete company and asked if they could do anything with that. “They said: ‘Yeah, I think we can do something with that,'” Anthony said. “‘We’ll throw it through the crusher and see what we come up with.'”
What they came up with—after crunching through about 5 tons of toilets—constituted roughly a quarter of the volume of one section of the sidewalk encompassed by the project (developers dubbed the pathway material “poticrete“). Add that to the impressive 80 tons of recycled concrete the project put to work in sidewalks, curbs and gutters, pushing the roadway asphalt’s recycled content up to 30 percent, and what you’ve got is Greenroads’s first-ever silver certification.
The Greenroads rating system was developed at the University of Washington (UW) to promote sustainable roadway construction. Its aim is to offer a roadway equivalent to the popular LEED rating system used for green buildings. According to principal investigator Stephen Muench, a UW associate professor of civil and environmental engineering, Greenroads is currently the only roadway accreditation system that is actively certifying projects.