Portland residents face a murky mess as heavy rains forced raw sewage to spill into the Willamette River early Saturday, city officials warned. The Bureau of Environmental Services confirmed that the Big Pipe system hit capacity around 3:30 a.m., leading to the unsavory blend of stormwater and untreated sewage directly flowing downstream from multiple outfalls near the Ross Island Bridge. As more rain is expected, the advisory may have to eventually include areas further upstream, officials indicated.
Citizens are advised to steer clear from the river to avoid coming into contact with the now bacteria-laden waters during the overflow and for 48 hours after it ceases. Normally, the river's water is deemed safe for recreational use, but the current conditions pose a notable health risk. The severity of the incident has prompted authorities to closely monitor the duration of this combined sewer overflow (CSO) via the online Big Pipe Tracker.
CSOs like this consist mainly of stormwater—about 80 percent—with the remaining 20 percent being sewage. Such events are relatively uncommon, occurring when heavy precipitation overwhelms the sewer system. Prior to the Big Pipe project's 2011 completion, a 20-year, $1.4 billion endeavor aimed at reducing overflows, the Willamette River was subjected to as many as 50 incidents yearly, with some lasting for days. Now, bolstered by the infrastructure improvements, the occurrence has dropped dramatically to an average of about four times each winter and once every third summer, according to city records.
This marks the first CSO event of the year for Portlanders, who now find themselves grappling with the unfortunate, yet tangible consequences of their city's ongoing battle with the elements. There is not an immediate estimate available for when the overflow is to expected to stop, per city officials. As the situation unfolds, updates on water quality and safety advisories remain available to the public for those seeking to safely navigate this temporary blot on Portland's environmental landscape.
