Can Heavy Rainfall Affect Willamette River Water Quality?

How can you tell if heavy rainfall has temporarily caused unsafe river water quality issues?  The City of Portland Bureau of Environmental Services (BES) reports any Combined Sewer Overflow event (CSO) that would impact upon the health and safety of people coming into direct contact with the Willamette River. 

Bureau of Environmental Services "River Alert Program" Reports any Combined Sewer Overflow Events

Portland's $1.4 billion dollar (Yes, that's billion with a "B"!) investment in the Big Pipe tunnels has resulted in a reduction of CSO events from an average of 50 events per year to just four events per year.

The last CSO event on the Willamette River occurred in June of 2014.  Link Mann, spokesman for Portland’s Bureau of Environmental Services, was quoted in an article published by OPB as stating, “In the space of 17 hours, we had 1.4 inches of rain. Those tunnels can handle up to about 1.2 inches in 24 hours.”

So, if it has been raining really hard all day, or even moderately hard for several days in a row, I check the BES site for any reports of a CSO event before I go kayaking, swimming, or paddling in or on the Willamette River.  Otherwise, if the river current isn't too strong, you'll find me and many of my neighbors out enjoying recreational activities on the water, even in the rain.  When your kayak, stand up paddle board, rowing skiff, etc. is sitting on your floating home deck at river's edge, launching in the rain becomes a wonderful opportunity to add some extra river recreation and enjoyment to your day!