When the housing agency in the city of Bellingham, Washington, replaced toilets in 400 residences with newer, dual-flush models, it found itself with a waste disposal problem. Luckily, one agency's five tons of old toilets turned into another agency's treasure.
That agency was the city's public works department, which was about to repave a section of a pedestrian sidewalk. It was looking to keep costs low but environmental credibility high. In the end, the two agencies formed a symbiotic relationship. The housing authority avoided a major disposal expense, and the public works department was able to crush the toilets down into an alternative to the aggregate they'd use for the concrete in the sidewalk.
The final mix, dubbed poticrete, contains about 20 percent crushed toilets by volume. That's about one dump-truck load of gravel, according to LiveScience. They city thinks it's onto something, and is creating a specification for using poticrete for flatwork concrete installations. Given the trend toward upgrading toilets to water-saving dual-flow models, it might have found a good way to keep even more johns out of its landfill.
Bellingham wasn't first to the toilet recycling game. And there are other uses for the crushed porcelain, too, including mulch and building foundations. But it is the first recipient of the a Greenroad certification. Greenroads is a rating system developed at the University of Washington to promote sustainable roadway construction.
Don't think the city just likes potty jokes. It recycled hundreds of old electrical light fixtures that were removed from the housing units, as well. The bulbs, ballasts, copper, and steel parts were separated and salvaged.