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The City of Portland, Oregon

Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Ave, Suite 613, Portland, OR 97204

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Willamette River water quality information online

People planning to enjoy some recreation on the Willamette River in Portland can check water conditions before they get out on the water. From May to October, Environmental Services staff collects and analyzes water samples weekly at five recreational areas on the river to track E. coli bacteria and water temperature. Environmental Services posts the results on the Willamette River Recreation Index at

Since the city completed the $1.4-billion combined sewer overflow (CSO) control program in 2011, E. coli results have been consistently low at most sites throughout the summer months. A count of more than 406 E. coli organisms per 100 milliliters of water is above the health standard set by the Oregon Department of Environmental Quality. E. coli counts in the Willamette are almost always well below that level. The June 3, 2014 E. coli count in river water at the Riverplace Marina, for example, was 5.

Combined sewers once overflowed to the river an average of 50 times a years. Since Portland controlled CSOs two-and-a-half years ago, there have been only seven CSO events.

The city’s green stormwater management infrastructure is an important part of the CSO control system. Green street planters, rain gardens, ecoroofs and trees keep millions of gallons of stormwater out of the combined sewer system.

Because of the success of the CSO control program, Portlanders can enjoy the Willamette River this summer knowing that the water is cleaner now than it has been in generations.

For more information contact Linc Mann, 503-823-5328.

The Bureau of Environmental Services works with Portland residents and businesses to protect water quality, public health, and the environment through wastewater collection and treatment, sewer construction and maintenance, stormwater management, and stream and watershed restoration.