Mystery in Canada: A Massive Island Appeared Out of Nowhere, Then Vanished Within Weeks

A massive island, covered in trees and vegetation and larger than a football field, suddenly appeared in Williston Reservoir in northern British Columbia, Canada, then vanished a few weeks later with the same mystery that surrounded its arrival.

The floating mass was first documented by a boater, whose photos and videos reached local resident Rocky Avery, who shared them on social media. Avery decided to circulate the footage in part because a major fishing tournament was about to take place in the area. He said he wanted to warn participants and alert British Columbia’s electric utility: "It was quite an amazing sight. I’ve never seen anything like it in my 40 years in this area."

At BC Hydro, the electric utility, officials initially found the sight hard to believe. Company spokesperson Bob Gammer said that in an era when photos and videos can easily be created using artificial intelligence, there was some doubt over whether the island was real at all. Satellite images from July 21 settled the question, confirming that the mass was indeed floating in the reservoir.

The island was located in the main body of Williston Reservoir, west of Finlay Bay and about 62 miles west of the W.A.C. Bennett Dam. According to BC Hydro estimates, it was about 460 feet long and 230 feet wide, an area of roughly 105,000 square feet, larger than a standard football field and approaching the size of one and a half fields.

But another twist came soon after. When company staff reviewed new satellite images, they discovered that by August 5, the island had already disappeared. Gammer said: "We took more updated images and we can no longer see the island. So now it’s gone."

Still, he said there is no certainty that the island sank: "It may have returned to a more sheltered area along the shoreline." BC Hydro believes the island is not expected to affect reservoir or dam operations, but officials are continuing to monitor the possibility that it may reappear.

One theory is that the island gradually formed near the shore over many years. Tree trunks and plant debris may have accumulated in the area, organic material decomposed, plants took root, and eventually trees grew on top of it, creating a large mass that looked like stable ground.

This year’s weather conditions may explain how that mass broke loose. Williston Reservoir filled to capacity after a snowy winter and prolonged summer rains, and in June and July, BC Hydro had to open the dam’s spillways to release water. According to Gammer, the reservoir had not reached such a high level in 14 years.

One possibility is that the unusual rise in water level detached the vegetative mass from its location, after which winds carried it into open water: "We can’t say with certainty where the floating island came from, but that seems like a plausible explanation."