The tree-covered island was roughly the size of two NFL fields before suddenly vanishing.
ByMark Elibert
August 31, 2026
A massive floating island mysteriously appeared on British Columbia’s largest reservoir before vanishing weeks later, leaving locals and officials wondering where it went.
The tree-covered mass surfaced on the Williston Reservoir in northern British Columbia in late July. Measuring approximately 70 meters wide and 140 meters long, it covered nearly 9,800 square meters, roughly the size of two NFL football fields.
A local boater photographed the unusual sight before sharing the footage with resident Rocky Avery, whose Facebook post attracted more than 140,000 views.
“It was a pretty amazing sight to see, never seen anything like that in my 40 years in this country,” Avery told CBC News.
“There’s a new floating island on Williston Lake, it was by the peace arm the other day not sure where it is today lol,” he wrote on Facebook.
The bizarre sight quickly drew comparisons online to Lost, the ABC series about plane crash survivors stranded on a mysterious island.
Satellite imagery from July 21 confirmed the island was real, showing the enormous mass floating west of Finlay Bay and roughly 100 kilometers from the W.A.C. Bennett Dam.
B.C. Hydro spokesperson Bob Gammer said officials were initially skeptical, partly because of the prevalence of AI-generated images.
“It’s certainly something we’ve not heard of before,” Gammer said. “And with not very many people reporting it, it was difficult to locate.”
“We’ve been taking more updated snapshots and we can’t see the object anymore. So it’s disappeared now,” Gammer said.
Officials believe the island may have drifted into a sheltered cove rather than sinking.
B.C. Hydro also has a theory about how it formed. The Williston Reservoir reached its highest level in 14 years following a heavy winter snowpack and steady summer rainfall.
Officials believe driftwood accumulated along the shoreline over several years, allowing plants and trees to grow on top of the decomposing material. When water levels surged, the entire mass may have broken loose and drifted into open water.
“We haven’t had a full reservoir in 14 years,” Gammer said. “We can’t pinpoint the origin of this floating island [but that’s] one explanation that seems reasonable.”
While the island remains missing, Avery warned boaters that floating and submerged trees have become dangerous because of the unusually high water.
“It’ll do a lot of damage to your boat,” he said. “So you got to be super careful.”
