Seth Baetzold - St. Croix River

Stillwater to Hastings

38.7 km km (23.6 miles)

11 hours, 6 minutes on 1 October 2022

Observed and documented by Michael D. Miller




  • Name: Seth Baetzold
  • Gender: male
  • Age on swim date: 27
  • Nationality: United States
  • Resides: Maplewood, Minnesota

Support Personnel


Michael D. Miller

Observer training was self-led from MSF YouTube Channel SF Marathon Swim Observer Training Videos recorded April 2021; Reviewed all material and made manual notes for future reference; viewed Segment 01 on 9/13/22, Segments 02-04 on 9/14/22, Segments 05-08 on 9/15/22, and Segments 09-11 on 9/17/22. Red Cross First Aid/CPR/AED online course completed September 2022. Marathon swims I have completed that had observers/swim reports: Catalina Channel 2018, Lake Tahoe Viking 2020, 20 Bridges Manhattan Swim 2021. There are 8 additional swims 10km or longer by me as recorded on LongswimsDB. South End Rowing Club member since 2013 (out of town member since 2014). USMS member since 2011.

Escort Vessel

Name Type Port
unnamed 21’ Ranger Reatta Bowrider Play Boat Afton, MN

Swim Parameters

  • Category: Solo, nonstop, unassisted.
  • Rules: MSF Rules of Marathon Swimming, without exception or modification.
  • Equipment used: Textile jammer swimsuit (Speedo), cap, goggles.

Route Definition

  • Body of Water: St. Croix River, a tributary of the Mississippi River in the states of Minnesota and Wisconsin. Both Minnesota and Wisconsin Department of Natural Resources describe this body of water from Stillwater, MN to Hastings, MN as Lake Saint Croix, a drainage lake, with surface area of 8393 acres, shore length of 124.5 miles, and maximum depth 78 feet. USGS Gauge at Stillwater indicates 4,000 CFS discharge for the day of this swim. Water elevation for the day of the swim was 675.2 feet at the start, and 675.3 feet at the finish of the swim as shown on attached USGS data. Changes in the flow rate and elevation of the Mississippi river near the finish of the swim was the possible cause of this ‘uphill’ swim.
  • Route Type: one-way
  • Start Location: Boom Site public boat ramp, Stillwater, MN (45.0800, -92.8002)
  • Finish Location: Point Douglas Park Beach (44.7502, -92.8127)
  • Minimum Route Distance: 38.7 km km (23.6 miles) (map)


No known previous swims of this route.

Swim Data

  • Start: 1 October 2022, 06:34:00 (Central Daylight, America/Chicago, UTC-5).
  • Finish: 1 October 2022, 17:40:05
  • Elapsed: 11 hours, 6 minutes, 5 seconds.

Summary of Conditions

Feature Min Max
Water Temp (F) 59 67
Air Temp (F) 54 73
Wind (mph) 0 7

GPS Track

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

Click to expand map.

Speed Plot

Nutrition: All feeds were powder mixed with water. There were three types of feeds: Vitargo Carbo, Skratch Superfuel, and Infinit:Speed fuel with electrolytes. All appeared clear, and swimmer requested that they be randomly given from the feed bag. Of the 13 bottles that were premixed by the swimmer, nine and one-half were consumed by the swimmer during the swim. First feed was 30 minutes after start of swim and at approximate 30 minute intervals for the duration of the swim.

Observer Log

Download PDF

Swimmer Statement

by Seth Baetzold

River Background

The St. Croix River is a tributary of the Mississippi River that flows in the states of Wisconsin and Minnesota and also defines a portion of the border between the two. The river is a National Scenic River-way under the protection of the National Park Service.


I had plans to swim the English Channel in July 2022. When I arrived the winds were too strong for the majority of my tide for myself to attempt a crossing. Returning home I wanted to encounter a similar swim in regards to length and temperature.

With no vacation left from work, I searched for a long distance swim in the Minneapolis/Saint Paul area.

A boat and captain was found docked on the Saint Croix River, a swimming area I am incredibly familiar with.

I cross the river each day for the last year and a half going to work. I even spent a few of my 1 hour lunch breaks swimming the width of the river during the summer months.

Using my experience of swimming at multiple locations along the river I developed a plan only 3 weeks prior to the swim.

First I needed to guarantee I would have a crew. Asking my brother Jared to kayak, a swimming friend Michael to be the observer, (he is also an engineer and I thought he would excel at recording all the important details), another friend Landon whom I swam a previous long distance river race with, a new friend Adam who kayaked a 10 mile lake swim a month earlier and lastly Ralph to shuttle cars.

Surprisingly everyone was available Saturday October 1st for the entire day.

Next was establishing the route. I knew the sun was up for a little less than 12 hours this time of the year. Swimming in the dark would not be a dealbreaker, it would just add to the difficulty.

I found a public dock to start at in Stillwater that would provide a lengthy swim.


After confirming the boat and my crew I decided to delegate tasks.

Ralph, Michael, my brother Jared, and I met at Panera September 18th to discuss the documentation, logistical, and details of the swim. This started the email chain between the group.

Saturday September 24th, Landon, myself, and Ralph utilized a zoom meeting to encompass the role of crew chief. We discussed feeds, boat positioning, logistics, and water conditions.

The rest of the planning was completed through texts, calls, and emails between the race start.

Saturday October 1st

Everyone arrived at the Stillwater Minnesota Boom Site Public Dock around 5:45 am. This is where logging workers in the 1800s would collect harvested trees and ship them down the river to sawmills. There was no trace of those efforts except a few markers and plaques dedicating the history.

We loaded our gear onto the motorboat, setup the kayak, and read the rules.

Starting at 6:34 am in the dark and cold water, I began my ultramarathon swim.

I only encountered 30 minutes of darkness before sunrise.

The sunrise was beautiful on the river, accompanied by the color changing trees.

I headed south on the river, following lights of the city of Stillwater and red bridge lights.

I passed the following bridges upon my swim:

  • Stillwater Lift Bridge

  • Saint Croix Crossing Bridge

  • Chicago and Northwestern Rail Bridge

  • I-94 interstate bridge

The experience was unreal swimming under the bridges.

The river contains long stretches and a few bends along our way.

The shorter stretches, bends and bridge sections passed by quickly with the longer routes dragging on.

I experienced a significant warming of water after the I-94 interstate bridge.

After this the river experiences higher cliffs to each side which provides great scenery for the short time I take a breath.

We came across more boats at this section. Anything from jet skis, yachts, and fishing boats.

The area is less developed at this part, with Afton State Park on the Minnesota side, and Kinnikinnic State Park on the Wisconsin side.

At no time did I feel unsafe due to fast moving boats since my brother, Adam, and Landon did an excellent job of ensuring the kayak, swimmer, and motor boat sandwich would be seen.

Passing Kinnikinnic State Park in Wisconsin was the furthest south I have swam in the river. The stretches after this being multiple miles long can provide a distortion of distance. Every feed I took I experienced trouble judging the distance swam. Nevertheless I kept pushing down the river.

Finally I saw the end. A small glimpse of the Point Douglas Park beach. After looking up a few times and not seeing any distance made, I decided to put my head down and grind out the last part.

I allowed myself to look up when the distance was less than half a mile and I found a small cheering section on the beach. This gave myself the last wind to finish the swim.

When I saw the sand of the beach I completed a dozen more strokes and started rising out of the water.

The small crowd started to cheer as I came on the beach. As I walked on sand I realized swimming 11 hours and then walking on uneven ground is not an easy task.

I have finished the first unassisted ultramarathon swim from Stillwater to Hastings Minnesota on the Saint Croix River.


Click to enlarge.



Weather Data