Just before noon on Saturday, July 19, 2025, Missoula swimmer Isabella Seagrave found herself in trouble. She was in the middle of Flathead Lake, somewhere east of Wild Horse Island, southeast of the small shoreside community of Rollins and about 14 miles north of Polson. The wind, which had seemed moderate from shore, was significant enough to create waves measuring up to four feet at times, with small white caps visible in every direction. Bella had already been swimming freestyle for roughly 12 hours, and her shoulders were barking. Forward momentum was slow at best and at times seemed impossible: one stroke forward and the lake pulled her three strokes back.
She was flanked by a support crew consisting of me — her uncle — her mom, Leslie Kemmis, her dad, Eric Seagrave, and her coach, Monica Bender, all taking shifts via a support kayak and a nearby pontoon boat, captained by longtime family friend Scott Stires.
At 23 years old, if she were to successfully complete the swim, Bella would become the youngest person to ever swim the full length of Flathead Lake — a 27.3-mile route from Somers to Polson.
And this wasn’t just the longest swim Bella had ever attempted, it was only her second open water swim of any real significance. The first came a month prior, during a six-mile training swim in Lake Coeur d’Alene. Before that she had only done a few short dips, nothing more than an hour.
Bella’s relationship with the water started before she could even walk. Her father, Eric, a lifelong swimmer who has managed public pools in Bozeman and Missoula for three decades, first introduced her to the pool as a baby. Throughout her youth, her parents took turns shuttling her across Montana for swim meets, driving through all sorts of conditions to support her.
As time marched on, Bella’s swimming progressed, and she rose through the ranks of every swim outlet that was available to her. From swimming with her dad in their hot tub as a toddler, to lessons offered through Missoula Parks & Recreation, leveling up and joining the Missoula Aquatic Club (MAC) at age 6, competing in her first swim meet at age 8, co-captaining MAC and Hellgate High School’s teams during her junior and senior years and even getting the honor to serve as an athlete representative to the Montana Swimming House of Delegates those same years. Ultimately, all of her time and dedication in the pool and the classroom earned her a scholarship to Long Island University in Brooklyn, New York, where she became the captain of its D1 swim team.
“I remember my friend Aidan Condit and I both crying together before all of our races and swim meets when we were just little kids,” Bella told me. “Then we swam together for years and years while on MAC and then coincidentally ended up swimming together some more when we were both on the same team at LIU. It’s pretty crazy when you think about it!”
The seed for this challenge had been planted the previous fall, in 2024. Bender — an accomplished swimmer who had conquered the English Channel, Loch Ness, Manhattan Island, and Catalina — had pitched the idea to Bella of a tandem Flathead swim. When an old shoulder injury forced Bender out, Bella decided to keep the plan. She trained all winter: five pool sessions a week, twice-weekly weightlifting, and eventually long runs, culminating in the Missoula Marathon in June.
By the time we gathered in the dark near midnight at the Somers boat launch on July 18, her plan was dialed. Her feeds included carb drinks, electrolytes, and, interestingly, Smucker’s Uncrustables. The route traced the western shore: past Lakeside, around Angel Point where three lights acted as our primary navigation beacons, threading between Goose Island and the mainland, down past Cedar Island, onward to Black Point, and eventually through the open water of Polson Bay.
At exactly 11:26 p.m., she started swimming.
And then, 12 hours in — she hit a wall. Up to this point in the swim, Bella had been mechanical. Focused. She wasted no time on small talk, not even during her closely monitored schedule of refueling and hydrating, or “feeds” as her crew referred to them. But now, in the middle of this vast body of water with the wind whipping and the waves rolling beneath her, we could see her beginning to crack. She let herself drift for a moment and then in a highly uncharacteristic and vulnerable moment, she called out to Bender.
“Monica,” she said. “How much more do you think I have?”
Bender didn’t hesitate. “I’d say you have about four more hours, Bella.”
Bella broke.
The sound of her crying made us all choke up. None of us could speak. I thought about how no one cruising along the nearby highways or sipping coffee in any of the lakeside luxury cabins had the faintest clue of this moment of raw emotion unfolding in the middle of Montana’s crown jewel and the largest natural freshwater lake in the western U.S. Bella had maintained her seemingly superhuman strength through the night, but now, in the gray morning light, an uncomfortable silence took hold.
But then, as if flipping a mental switch, Bella took a breath. Her hot pink swim cap was once again half buried in the water and her arms began churning.
Left arm. Right arm. Breathe. Repeat.
No one cruising along the nearby highways or sipping coffee in any of the lakeside luxury cabins had the faintest clue of this moment of raw emotion unfolding in the middle of Montana’s crown jewel.
Not quite knowing what state Bella was in, we turned our focus to pushing out of the middle of the lake and into Polson Bay, which would represent something akin to rounding third base.
“Once we pass that island, it’s a straight shot to Polson,” I said aloud, and then immediately hoped Bella hadn’t heard me. Thankfully, she didn’t. Because while technically true, that “straight shot” would stretch on for over five more grueling miles. I think we knew, intuitively, that any mention of distance or time should be avoided with Bella at this point. We retreated into silence.
The vast section of open water that stretches from about Cedar Island south through the Narrows and into Polson Bay can’t be cheated. There is no shoreline to hug. No comforting land formation to set your sights on. No goal that seems attainable enough that your mind can focus on a small victory. Flathead’s famed Wild Horse Island — usually a welcomed sight — is, for someone swimming across the lake, a landmark that simply can’t go away fast enough. It offers no tick mark of progress. It lends no encouragement. Twelve hours into a swim, it actually demoralizes. The answer to getting past it? Maybe it was in Bender’s words she delivered to Isabella on several occasions: “Just keep swimming.”
“You see that bridge up there? That’s fucking Polson!”
The Narrows, which we were entering, marked a significant geographical milestone for us, but the reality for Bella remained the same. She still had to lift her arms out of the water over and over if she wanted to make any progress. She still had to fight the wind and waves. And she now had to also see her crew become a bit more frantic as we worked to alert every passing boat and jet ski to the fact that there was an exhausted human in the water. Promising objects on the horizon grew larger, then didn’t. Hours passed. The finish line felt farther away than ever. At one point, maybe in an attempt to give Bella a burst of energy, someone yelled, “You see that bridge up there? That’s fucking Polson!”
Whether it helped or not, who knows. But she kept going.
After a remarkable feat of physical and mental strength, at 5:03 p.m., after 17 hours, 36 minutes, and 57 seconds, Bella walked out of the water at Salish Point Park.
Days later we confirmed with Polson local Mark Johnston, the founder of FLOW Swimmers, and the person who keeps meticulous records of all known Flathead Lake swimming completions via his website flowswimmers.com. Bella is the ninth documented person to swim the length of Flathead Lake, and the youngest to ever do it.
“I’m so proud of Bella’s accomplishment,” Bender said a few days later. “It’s a feat of grit, endurance, mental fortitude and sheer determination. And it was such a privilege to share something that I love with a friend and to be a part of her first marathon swim.”
Bender is right. The swim was all of those things. It was also the product of months — and a lifetime — of preparation.
