October 3, 2014 – Tedious is the only way to describe the process of raising a performance high wire between two buildings. (Left) Leo Burnett Building as seen from the observation deck of Marina City’s west tower. (Click on image to view larger version.)

On Thursday, October 30, three days before Nik Wallenda will need it to walk across the Chicago River, union electrical workers will lift a steel cable, 0.75 inches in diameter, so that it stretches from the 61st floor observation deck of Marina City’s west tower to the roof of the 46-floor Leo Burnett Building.

A second cable will be stretched from Marina City’s west tower to its east tower. This will happen between 9 p.m. on Thursday and 6 a.m. on Friday.

Electrical workers specialize in rigging cables between buildings. Granted, those cables usually carry electricity, but the process is the same for high wire acts, explained Nik Wallenda on Wednesday.

Small, custom-built cranes will hang over the edge of each building’s roof and raise the cable without it touching the side of the building.

(Above) A parapet-mounted crane.

With the high wire crossing the river at ground level, ropes will be lowered from the cranes on each building and attached to the high wire. The wire, at least 341 feet long, will then be lifted to the required height – 543 feet above ground at Marina City and 635 feet at Leo Burnett Building.

Both buildings will lift the high wire at the same time, says Wallenda, “almost as in a tug of war. We’ll pull a little bit to Leo Burnett, a little bit toward Marina City, back and forth, back and forth, until it makes it up to the top.”

After that come the support wires, anchored in concrete, which will keep the main wire from swaying.

“It’s a tedious process for sure but something that these guys are experts in the field at doing.”

Though Wallenda himself is not involved with raising the high wire, his chief engineer and his father will be in Chicago to monitor the work.

The stunt will happen at about 7 p.m. on Sunday, November 2, during a live broadcast on Discovery Channel to 220 countries.

After the show, the wire will start to be taken down that night. All remnants of the broadcast should be gone by Tuesday, November 4.

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