Angela "Angie" Williamson - Lower Willamette River

Clackamette Park to Kelley Point

38.3 km (23.8 miles)

13 hours, 43 minutes on 23 July 2022

Observed and documented by Robin Donovan, Matthew McClellan, Dena Marshall




Support Personnel


  • Robin Donovan - Observed a Sauvie Island Circumnavigation attempt in Portland a few years ago. Open water/ice swimmer, free diver, and sailor.
  • Matthew McClellan - Observed and crewed for two Ironman Triathlons. Open water/cold water swimmer.
  • Dena Marshall - Observed and supported one Portland Bridge Swim unofficial swim. Trained in CPR/First Aid, completed one supported Lake Titicaca 8km swim, regular year-round open water swimmer, former triathlete.

Escort Vessel

Swim Parameters

  • Category: Solo, nonstop, unassisted.
  • Rules: MSF Rules of Marathon Swimming, without exception or modification.
  • Equipment used: Textile swimsuit (Jolyn Brand bikini. Top: Tomcat & Bottom: Zoe). Yellow MSF silicone cap, Warmiehomy goggles (perscription -2.0), Mack’s Ear Seals earplugs, RuffWear Beacon light.

Route Definition

The route is the course of the Lower Willamette River from the confluence of the Clackamas River to the confluence with the Columbia River. The route begins at Clackamette Park in Oregon City, OR where the swimmer will enter the Clackamas River from shore via boat ramp to the tip of the Portland peninsula, and into the Columbia River, at Kelley Point Park in Portland OR. The route follows the main channel of the river and eschews coves and channels with including the channel between Toe Island and Ross Island, the route remains with the main channel at all times. The route goes through five cities and is approximately 39,500 meters/24.5 according to Google Earth.

  • Body of Water: Lower Willamette River
  • Route Type: one-way
  • Start Location: Clackamette Park, Clackamas River (45.3725347, -122.603058)
  • Finish Location: Wingdam at Kelley Point (45.6513769, -122.762763)
  • Minimum Route Distance: 38.3 km (23.8 miles) (map)


I am not aware of historical swims. I have made a good faith effort to search local newspapers and spoke with “old timers,” and local marathon swimmer Michelle Macy. Many swimmers have swum the sections of river that compose this swim, but to the best of my knowledge, no one has linked up the sections into one continuous swim until I completed it without following MSF rules on August 21, 2021. Full write up on that successful attempt can be found at The bulk of the route follows the Portland Bridge Swim course, with the addition of 8 miles between Clackamette Park and Sellwood and 5 miles from St. Johns to Kelley Point.

Swim Data

  • Start: 23 July 2022, 05:28:52 (Pacific Daylight Time, America/Los_Angeles, UTC-7).
  • Finish: 23 July 2022, 19:12:51
  • Elapsed: 13 hours, 43 minutes, 59 seconds.

Summary of Conditions

Feature Min Max
Water Temp (F) 65.3 74.7
Air Temp (F) 57 75.5
Wind (mph) 1 15

GPS Track

Trackpoint frequency: 10 minutes. Download raw data (CSV).

Click to expand map.

Speed Plot

Observer Log

Download PDF

Transcribed Log


by Angie Williamson

What inspired you to do this swim?

I love the Willamette River, it's been a source of so much joy in my life and it's where I completed my first marathon distance swims. Unfortunately, the Willamette has a history of poor water quality and unsafe beaches, though much improved the reputation remains. I did this swim in part to raise awareness in my community about the Willamette as a safe place for recreation and to draw awareness to the work that still needs to be done to keep the river clean. I used this swim to raise funds for organizations that do just those things, Human Access Project and Willamette Riverkeeper. I also raised funds for Black Swimming Initiate, a local organization that provides free drowning prevention and basic water safety for people of color in the Portland metro area.

I was inspired by local and regional marathon/cold swimmers: Michelle Macy, Jessica Kieras, Cindy Werhane, Shannon House Keegan, Stephanie Zimmerman, Amanda Winans, and Jerome Leslie. These swimmers all influenced my decision to do this swim for various reasons, but mainly because they look at a map and ask, “Can I do that?” I looked at a map of the Willamette shortly after my first time swimming in it in 2017 and wondered if I could swim from the confluence of the Clackamas to the confluence with the Columbia, at nearly 25 miles I deemed it out of my reach. In 2021 I decided to see just how far I could go and to my great surprise, and delight, I made it the whole way. It was an amazing swim. I decided to do it again for ratification from MSF so that the greater marathon swim community will have access to key information to complete such a unique and wonderful swim.

Describe how you planned for the swim.

To plan for the swim I consulted experienced marathon swimmers online using the MSF forum and by speaking with Oregon marathon swimmers, including Michelle Macy and Jessica Kieras. I reviewed the rules of marathon swimming and planned my route accordingly. I created a Google folder and spreadsheet to organize the support crew and define roles using information from the MSF website. I sought volunteers among my friends and fellow swimmers to serve as support crew. When planning the dates and start time of the swim I consulted tide tables, reviewed rainfall and temperature data from the National Oceanic and Atmospheric Administration, and my own notes on temperatures and algae blooms to ensure the best conditions for the swim. I plotted the route based on swimming each section of the swim and consulted Google Earth to ensure the planned route stayed within the main channel.

How did the swim go, generally? Did you face any unanticipated challenges?

The swim felt remarkably good this year, I felt well prepared with the planning and following my training and feed plans- the weather and conditions were perfect. Overall, the swim went very well! It started with seeing the biggest sturgeon I’ve ever seen swimming right underneath me in the Clackamas. The challenges that came up were related to the crew and some role confusion and mechanical/weather problems- I felt great the whole way. There was some confusion about what to do with the tracker once I met up with the big support boat, Ginger, but I was unaware of it at the time as I just kept swimming the planned route. We also had a problem with the canoe motor fuel line detaching and the kayak getting swamped and nearly flipping about a mile out from the wingdam, but again, I wasn’t aware of that at the time as I continued the route and could see the wingdam at the end. The last three miles were hard and the wind picked up with a lot of chop, but it was easier on me than the canoe and kayak. In the water, I had some minor cramping in my claves that was alleviated with electrolytes, some nausea due to diesel jet boat wake, and general soreness- but nothing unexpected or that felt like an injury. I used CarboRocket with each feed but had trouble eating solid food, nothing tasted good after about the 8th hour (except bacon and gummy bears) but I made sure to drink and eat as much as I could. I walked out the quarter mile from the wingdam beach to the parking lot without help, and felt surprisingly good for spending nearly 14 hours in the river.


Click to enlarge.




  • USGS data for Williamette River @ Portland - Download PDF
  • NOAA tide predictions for Portland @ Morrison St Bridge - Download PDF