Janine Serell - Flathead Lake (width)

East shore to Wild Horse Island

16.75 km (10.4 miles)

7 hours, 16 minutes on 29 July 2022

Observed and documented by Kate Gruenwald




  • Name: Janine Serell
  • Gender: female
  • Age on swim date: 60
  • Nationality: United States
  • Resides: Charleston, South Carolina

Support Personnel

  • Ed Riley - boat pilot
  • Steve Gruenwald - crew
  • Manami Ono - crew
  • Kate Gruenwald - observer

Escort Vessel

Name Type Port
unnamed pontoon Polson Boat Rentals

Swim Parameters

  • Category: Solo, nonstop, unassisted.
  • Rules: MSF Rules of Marathon Swimming, without exception or modification.
  • Equipment used: Textile swimsuit (Old Lady Moderate cut Speedo in Aubergine), TYR prescription goggles, cap.

Route Definition

  • Body of Water: Flathead Lake, Montana
  • Route Type: one-way
  • Start Location: Beardance Picnic Area (47.956046, -114.035853)
  • Finish Location: Osprey Cove, Wild Horse Island (47.853080, -114.199653)
  • Minimum Route Distance: 16.75 km (10.4 miles) (map)


LongSwimsDB: Flathead Lake.

Swim Data

  • Start: 29 July 2022, 08:30:00 (Mountain Daylight Time, America/Denver, UTC-6).
  • Finish: 29 July 2022, 15:46:54
  • Elapsed: 7 hours, 16 minutes, 54 seconds.

Summary of Conditions

Feature Min Max
Water Temp (F) 71 76
Air Temp (F) 66 94
Wind (mph) 0 4

GPS Track

Trackpoint frequency: 20 minutes. Download raw data (CSV).

Click to expand map.

Speed Plot

Nutrition: The swimmer alternated between Hammer Perpetuem (chocolate of course) and Nuun Electrolytes and a fun flavor of Gu every 40 minutes. Additionally on most feeds the swimmer consumed a packet of Guldens Mustard to help ward off cramps in her feet and calves.

Observer Log


by Janine Serell

I’m not exactly sure when I first saw a photo of Flathead Lake but I do remember the water was gin clear and the stones were such a pretty array of colors, I was intrigued. It was during one of those phone calls to my friend Steve Gruenwald a couple of years ago when I mentioned it to him and lo and behold he had also seen some photos which made him want to go swim it too. It takes some time to align 2 people’s swim calendar for something that big but in the Fall of 2021 we committed to going there in the Summer of 2022.

Originally Steve was considering the length, but that was bigger than I wanted to do this year having come off swimming the length of Tahoe in 2021. So I mapped out what I thought was still challenging but not stupid hard width crossing. I was planning on swimming from Big Arm State Park to Yellow Bay State Park which is approximately 14 miles, that seemed just right! I was also excited to be pioneering a route, something I had never done before, another milestone in my swim journey. We decided we could use another set of hands to support these swims and our friend Ed Riley agreed to come support and swim himself. A plan was set in motion for the last week in July 2022.

Well none of my spring training happened as planned, I was out of the water with various issues for about 7 weeks going into this swim. I had swum a 6 mile event in Seneca Lake NY and thought a few more days rest beforehand would be best and so I would swim second. Ed and Steve decided that the would do the same 14 mile route tandem…..lucky me they went first. During their swim we learned that there are north and south currents in the main body of the lake that they swam across and they also had a stiff head wind for the first couple of hours. Having learned from their mistakes I called an audible and decided on a different route. I also checked my route with Marc ( owner of Polson Boat Rental – they were great to work with!) who agreed the ~ 10 mile long diagonal route from Dancing Bear Picnic Area to Osprey Cove would be a sweet swim and the currents and winds would be in my favor.

The Swim

It was a beautiful morning as we boated up to the start. We had tried to scope it out the previous day from the land but the path to the water was pretty steep and I’m not the most graceful of girls so we figured we could use google maps to find it from the water and that worked fine.

This was truly one of the happiest days of swimming in my life! Let’s start with the environment; the water was low 70’s most of the day, it’s ridiculously clear, very low boat traffic, clear air, an occasional twig or log (which I never saw), no snakes or sharks or anything that could hurt you, just beauty. And I was so grateful to the crew on the boat! Ed crewed me around Manhattan, no one I trust more to keep me safe in the water. Steve and I have shared multiple swim adventures before and his vibe I knew would keep me swimming happy all day long. Kate and Manami were rock solid in being able to watch over me and we had spent the previous day together crewing and observing Ed and Steve, I couldn’t have been in better hands.

The very first person I observed for was Eileen Burke swimming Ederle and her husband said watch this, every time I stop to feed her she will say ‘already?’. And she did because her swim was so joyful that it just flew by. I’ve had moments of a swim like that but this one I truly felt that way for almost all of it. I even asked if they were really feeding me on 40 minutes and not 30.

I don’t really look at the land much when I swim, I look at the water mostly. But at one point I saw an island and was so dissapointed thinking it was Wild Horse Island and that my swim was almost over and running the map through my head I was trying to decide how to extend it. Luckily I was wrong, the island I saw was not Wild Horse and I still had a ways to go.

As we got closer Manami joined me in the water which was just lovely. I am a social swimmer in a solo sport, so having a swimmer jump in with me and sharing the experience makes me happy. Also she swam out my pain meds! And when we got close to the island there was an increase in boat traffic Steve jumped in with a swim buoy on to help keep me safe and to make me more visible to the traffic.

I finished on the rocky beach at Osprey Cove exactly as planned and honestly I’d like to get back to that lake again someday to swim again.

Flathead Lake should be crawling with swimmers, its truly that beautiful. I love Lake George and Lake Tahoe and the Finger Lakes in NYS and all the pretty lakes in Northeast Kingdom Vermont and I will continue to swim those too but I have also learned from this adventure that there are lots of lakes out there to be explored that not very many people swim and we should!