What Does WCO Stand For in the Uniform Plumbing Code?

If you’ve ever flipped through the Uniform Plumbing Code (UPC) and stumbled upon the acronym “WCO,” you’re not alone. Many plumbers, inspectors, contractors, and even curious homeowners ask: “In the Uniform Plumbing Code, what does WCO stand for?” It’s a valid question—especially when compliance, safety, or licensing is on the line. In this article, we’ll…