In June, Eurotunnel said closing its service tunnel, which runs next to the main tunnel, would pose a safety risk to passengers and affect essential maintenance work.
Bushby, whose Los Angeles-based team has been in close talks with the French authorities, said he expected the swim to take “three or four days”.
“It’s all about getting the job done and getting home alive,” he said.
“We’re still getting to work on the details.”
Between swimming sessions, Bushby intends to rest on a support boat.
Bushby has previously completed a long-distance swim.
In 2024, he swam 186 miles (300km) across the Caspian Sea as a means of avoiding having to enter Russia or Iran due to tensions with the West.
But he said there had been no time to train for this latest challenge.
“I’ve been too busy planning the route,” he said.
To date, Bushby has covered 30,516 miles (49,110km), including crossing the dangerous Bering Strait from Alaska to Russia and the infamous Darién Gap between Colombia and Panama.
However, he said securing visas and failing to gain permission to use the Channel Tunnel had been the hardest part of the expedition.
“Organising how I’m going to get back into the UK has been a nightmare,” said Bushby. “It’s been a real rigmarole. But we’re getting there and the aim is to be back in Hull by November 1st.”
Bushby’s mother, Angela, has promised to greet her son at the front gate to her home, where he and his brother were raised.
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