The plan is a backup to Wallenda's own rescue plan, which would use a system of pulleys and baskets, The Buffalo (N.Y.) News reported Saturday.
"One of the conditions of the Niagara Parks Commission contract with Nik Wallenda was that he was supposed to furnish his own rescue plan," said Douglas Kane, chief of the Niagara Parks Police Service in Canada. "We've reviewed it. We're happy with it."
Park police in Canada and the United States purchased a $3,800 zipline system to use should Wallenda fall and be left dangling from a tether attached to the 2-inch cable spanning the Niagara gorge. A team of 10 park police have been practicing using the zipline on a weekly basis since April.
"So we do have a backup plan to their backup," Kane said. "However, I think his should suffice."
About 120,000 spectators are expected on site to watch Friday as the daredevil attempts to walk a tightrope from the U.S. to the Canadian side of Niagara Falls.
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