
Beaverton’s Combined Sewer System: What Homeowners Need to Know
Beaverton, like many cities in the Portland metro area, operates a combined sewer system (CSS) that collects both stormwater runoff and sewage in the same set of pipes. While this infrastructure is common in older urban areas, it poses unique challenges—especially during heavy rain events. Understanding how the combined sewer system works, what risks it presents, and how you as a homeowner