A tree-covered island roughly the size of a Canadian football pitch appeared on Williston Reservoir in northern British Columbia, Canada, last month, only to vanish by August 5. The land mass, about 70 metres wide and 140 metres long, was confirmed by satellite imagery before it disappeared.
Local resident shares footage
Rocky Avery, who described the island as "pretty amazing," said footage and photos were initially captured by a boater before being shared with him. Avery later posted them online.
"It was a pretty amazing sight to see, never seen anything like that in my 40 years in this country," he said. "There was a big fishing derby coming up, so I wanted to make sure everybody was aware of what was going on. And I wanted B.C. Hydro to know too that it was out there, just in case it was floating down their way."
BC Hydro initially puzzled
BC Hydro spokesperson Bob Gammer told CBC that he was unconvinced at first, given how common AI-generated content has become, explaining it was "difficult to locate." He admitted it wasn't something they'd "heard of before" and that few people had reported it, but satellite imagery confirmed its existence. Further shots were taken, but they could no longer see it. "It's disappeared," he noted.
Possible explanations
Gammer suggested the island may not have submerged. "It doesn't mean it's gone to the bottom of the reservoir. It may have returned to a more sheltered area along the shoreline," he said. He theorised that driftwood could have gathered along the shoreline over many years and stayed long enough for trees to grow from the debris.
Williston Reservoir recently filled to capacity due to snow and rain, prompting BC Hydro to open its spillways in June and July. High water levels may have caused the island to become untethered, with wind pushing it out into the water. Gammer said they hadn't seen such levels in 14 years and suggested the theory "seems reasonable," adding that the unusually high levels had pulled more debris into the water than expected.
Similar floating islands have been spotted around dams elsewhere, including Africa's Lake Victoria and Lake Chippewa in Wisconsin, notably the "Forty Acre Bog" peat island.
