Mary Singer slipped into the dark water off Sandy Shores at 3:56 a.m. on August 12 wearing nothing but a bathing suit, a cap, and goggles. Fifteen hours and 28 seconds later, the 51-year-old Vashon Island resident climbed out having become the only person on record to swim all the way around her own island.
Singer's roughly 32-mile route made her the first documented person to circumnavigate Vashon Island, according to The News Tribune, which spoke with Singer on the Friday after her swim. Her support crew measured the distance from the boat at 33 miles, while Vashon Island itself has the shortest recorded circumnavigation distance of the region's islands at about 31 miles — shorter than nearby Bainbridge Island's roughly 25-mile loop. The News Tribune reports her official time of 15 hours and 28 seconds remains pending ratification.
Singer swam skins-style the entire way, forgoing the wetsuit she gave up back in 2023 and training year-round in 56-to-60-degree water, per the same report. She told the paper she expected water temperatures of 58 to 62 degrees during the swim itself, though Puget Sound reportedly reached as warm as 65 degrees at points along the route. National Weather Service data shows summer water temperatures in Puget Sound typically range between 50°F and 62°F — conditions that can trigger cold water shock and rapid muscle incapacitation within minutes for anyone without protective gear, underscoring just how demanding a 15-hour unassisted swim through those waters can be.
A Route Planned by a Fellow Circumnavigator
The course was mapped by Stephanie Zimmerman, who completed her own counter-clockwise unassisted swim around Bainbridge Island in September 2024 and serves as vice president of the Northwest Open Water Swimming Association. Zimmerman planned Singer's entire Vashon route, according to The News Tribune's report. Andrew Malinak, NOWSA's president, was the first person recorded to swim around Bainbridge Island, completing that 25.5-mile clockwise route in 12 hours and 23 minutes back in 2015.
Two NOWSA observers monitored Singer throughout the swim, conducting hypothermia and kidney-function checks and holding the authority to stop the attempt if necessary, the paper reported. Singer herself serves as clerk on NOWSA's board alongside Malinak and Zimmerman, a fact that highlights how close-knit the region's marathon swimming community remains. Under the international Rules of Marathon Swimming that NOWSA follows, an unassisted or “skins” swim requires only a standard swimsuit, a single cap, and goggles — touching a support vessel or using any buoyancy aid disqualifies the swim from unassisted status.
Singer kept fed with liquid nutrition every 30 minutes and a carb gel every two hours, and she was not allowed to wear her Garmin watch during the swim, per The News Tribune. Two support boats accompanied her, and observers reported spotting porpoises and seals along the way, though no orcas turned up. “I love currents,” Singer told the paper, a comment that speaks to how she approaches the unpredictable tidal conditions rather than fighting them.
From Coronado to the Triple Crown to Puget Sound
Singer's path to Vashon started far from Washington's cold water. She completed her first marathon swim around Coronado Island in San Diego in 2021, finishing in 5 hours, 16 minutes and 50 seconds after taking up open water swimming in 2019. She moved to Vashon from Tacoma in 2016 and now works as an HR professional in Seattle, commuting from the island she calls home.
Last year, Singer completed the Triple Crown of Open Water Swimming — the Catalina Channel, a circumnavigation of Manhattan, and the English Channel, totaling 69 miles — finishing her final leg, the English Channel crossing from England to France, in 13 hours and 52 minutes on August 23, 2025. Roughly 400 people worldwide have completed the Triple Crown, according to The News Tribune, a milestone shared by other recent swimmers including a Raleigh teen who completed the achievement at 17 and a Las Vegas swimmer who crossed the Channel earlier this month.
Singer's first Puget Sound skins swim lasted just 45 minutes, a stark contrast to the 15-hour endurance test she just completed. She swam in a bathing suit without a wetsuit throughout the Vashon attempt, continuing the shift she made away from thermal protection in 2023.
Community Ties and What Comes Next
Singer partnered with the nonprofit Vashon Nature Center for the swim, raising more than $9,000 to spotlight marine conservation work along the island's coastline, according to the organization. Singer grew up on Vashon Island learning to swim at the local public high school pool, giving the fundraising partnership a personal throughline back to the community that shaped her.
Her husband, Katsumi Purbeck, was part of her support network for the effort, The News Tribune reported. Singer said people can do things once they believe those things are possible, and she told the paper she plans to pursue more long swims in the Puget Sound area. Her next stop is a lower-stakes affair: the Mount St. Helens Classic, a Labor Day event scheduled for September 7, which Singer described to the paper as more of an event than a serious race.
Puget Sound's open water carries real risk alongside its appeal to swimmers like Singer. Hoodline previously reported on a late-night Seattle swim that ended in tragedy, a reminder of how quickly cold water can turn dangerous even for experienced swimmers. NOWSA sanctions seven open-water marathon routes across Washington, including crossings of the Strait of Juan de Fuca and Lake Washington alongside circumnavigations of Bainbridge, Mercer, and Maury Islands — a roster that Vashon Island now effectively joins through Singer's swim, pending official ratification.
