Is the attempt to make environmentally friendly roadways doomed to wind up in the toilet? Actually, it may be the other way around. To earn a green certification, the Meador Kansas Ellis Trail in Bellingham, Washington, included 400 recycled commodes in the concrete.

Greenroads is a new rating system, developed at the University of Washington, which judges the sustainability of roads and road construction projects. Under the system, projects must incorporate 11 specific features, such as dealing with waste from the construction process, as well as some optional practices, which in the case of the Meador Kansas Ellis Trail included recycling.

The toilet interment helped the project win the first official Greenroads nod, earning a silver certification. About 30 percent of the pavement consists of recycled concrete and, yes, crushed-up toilets, nicknamed “poticrete.”

But this project’s sustainability relies on more than old thrones. The Trail’s porous concrete prevents excessive run-off; it’s illuminated with low-energy lighting; and its mere presence encourages bicycle and foot traffic. These green features mean that sustainable roadways can be more than a pipe dream.

—Sophie Bushwick

[The above text is a transcript of this podcast.]