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Holiday closure

Most City of Portland offices will be closed Monday, July 4, to observe Independence Day.

Check the Rec: Willamette River Water Quality Testing

Information
Three people jumping into the Willamette River to go swimming.
Are you planning to swim, boat, or play in the Willamette River? The river’s water quality is safe for swimming and other recreation thanks to the Big Pipe Project and other water quality improvements. Check for yourself. We test the river for bacteria counts regularly and post results here.
On this page

Weekly Summer Testing

Environmental Services samples for E. coli bacteria and water temperature at five popular Willamette River locations each week from late May to September. Samples are taken on Wednesdays, and results are posted by Friday—just in time for the weekend. Results are consistently safe.

Monthly Testing

Each month, year-round, Environmental Services collects water samples at three locations to track long-term water quality trends.

Photo shows Environmental Services field scientist taking river water samples from the Firehouse Dock with the Willamette River and downtown Portland in the background.
An Environmental Services field scientist collects river water samples as part of the weekly summer water quality testing.

Staying Safe on the River

Keep in mind many factors affect your safety on the river. These include water temperature, currents, and debris in the river, as well as your skills and ability in the water. While cold water is healthy for fish, low temperatures can be uncomfortable and even unsafe for people. Know the water, know your abilities, and stay safe while enjoying the river.

Algae Blooms

You can also check Oregon Health Authority recreational and fish advisories:  Occasionally, harmful algae blooms may form in slow-moving portions of rivers and lakes during hot weather. If you see water that looks green or has a coating, the advice is, “if in doubt, stay out.”

Where to Swim

Portland Parks & Recreations operates Poet’s Beach and has other tips for where to swim and how to stay safe when recreating in the Willamette River.

How Did the River Become Clean Enough to Swim and Play?

The federal Clean Water Act has led to vast improvements in water quality in rivers throughout the country. In Portland, those improvements include ratepayers’ investment in the $1.4 billion Big Pipe project—the largest public works project in Portland history. Since Environmental Services completed the project in 2011, almost all combined sewer overflows (CSOs) to the Willamette River have been eliminated. With that drop in sewage, comes a drop in E. coli bacteria, an indicator of fecal matter and the single biggest health concern for swimming and other direct-contact recreation, according to the state Department of Environmental Quality. Other E. coli sources include poop from wildlife and pets. (Thank you for picking up after your dog.)

Find out other ways you can help keep our rivers clean and healthy