At least 400 toilets were recently used as aggregate in sidewalk cement, also known as "poticrete," in the town that sits about 25 miles south of the Canadian border.

"The toilets were landfill bound," said Freeman Anthony, project engineer for the city of Bellingham Public Works Department. "There was really nothing you could do with them."

That is, until Anthony brought together a group of public and private entities. The commodes came from a low-income housing project that was being renovated by the Bellin...