Sept. 1, 2021 Update: This summer’s extreme heat is leading to cyanobacteria blooms in Portland’s stretch of the Willamette River. Oregon Health Authority’s advice is to be aware of your surroundings and be alert to the signs of cyanobacteria. View the latest OHA advisories but know that testing is limited and the safest option is: When in doubt, stay out. For City of Portland bacteria testing, see below.
Are you planning to swim, boat, or play in the Willamette River this summer? The river’s water quality is safe for swimming and other recreation thanks to the Big Pipe Project and other water quality improvements made in recent decades under federal and state laws.
You can check for yourself. Environmental Services samples for E. coli bacteria and temperature at five popular Willamette River locations each week from late May to September. Samples are taken on Wednesdays, and results posted by Friday—just in time for the weekend.
Weekly summer testing
- Cathedral Park Boat Launch, River Mile 5.6
- Portland Boathouse Dock at Hawthorne Bridge, River Mile 12.9
- Riverplace Marina Boat Dock, River Mile 13.2. This location is next to Poet's Beach.
- Willamette Park Boat Launch, River Mile 15.7
- Sellwood Riverfront Park Dock, River Mile 16.4
Each month, year-round, Environmental Services collects water samples at three locations to track long-term water quality trends.
- Railroad Bridge, River Mile 6.8
- Morrison Bridge, River Mile 12.7
- Waverly Country Club, River Mile 17.9
Keep in mind many factors affect your safety on the river, including temperature, currents, and debris in the river as well as your skills and ability in the water. Remember, cold water is healthy for fish, but it can be uncomfortable and even unsafe for people. Know the water, know your abilities, and stay safe while enjoying the river.
You can also check Oregon Health Authority recreational and fish advisories: Occasionally, harmful algae blooms may form in slow moving portions of rivers as well as 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
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 completion in 2011, almost all combined sewer overflows (CSOs) to the Willamette River have been eliminated. With that drop in sewage exposure 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!)
Because of the public’s interest in recreation on the Willamette River, Environmental Services tests for bacteria weekly during the summer. It’s one way you can be assured of bacteria levels and see and experience the results of your investment in the Big Pipe project.