Portland’s Big Pipe hit 100% capacity at about 6:26 a.m. Thursday. That does not mean the system failed. It means the city’s giant underground overflow tunnels filled up during heavy rain, leaving no more room to store the extra mix of stormwater and sewage flowing through Portland’s older combined sewer system. Once that happens, overflow can occur. Water watchers know: Sometimes, you can’t swim in the Willamette River. That’s because when the wastewater system gets inundated with water, it can overflow, sending a mix of stormwater and sewage into the river that bisects Portland. Nowadays, these overflow events happen roughly four times a year. But they used to happen much more frequently, sometimes 50 times a year. Read more at the link in our bio. 📸: Oregonian Staff #portlandbigpipe #portlandoregon #portland #theoregonian #sewersystem #willametteriver