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Unfortunately, after the tunnels were abandoned in 1959, the redundant access shafts were mostly bricked up and forgotten about. At least, this was the case until the early hours of the 13th when the basements of City Hall, The Merchandise Mart, Chicago Hilton and Towers, the Federal Reserve Bank, and many other business district buildings and subways began to flood.
It was decided that the breached section of the tunnel underneath the river had been slowly deteriorating under pressure created by a piling being driven too close to the tunnel wall during remedial work on the Kinzie Street Bridge back in 1991.
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Allegedly, urban explorers had noticed what was initially a small leak inside the tunnel, which had been reported during a cable inspection. There was a delay in deciding who would fix it.
Chicago’s resulting flood (or ‘leak‘ as it was called for insurance purposes) caused around $1.9 billion worth of damage. After attempting to close the breach by dropping rocks from above, the tunnels were drained, drilled, and plugged. To prevent further problems, the section underneath the river was eventually sealed off from the rest of the network, and the tunnels have since been secured after a terrorist threat.
Compiled by Dr. Neil Gale, Ph.D.
Chicago’s resulting flood (or ‘leak‘ as it was called for insurance purposes) caused around $1.9 billion worth of damage. After attempting to close the breach by dropping rocks from above, the tunnels were drained, drilled, and plugged. To prevent further problems, the section underneath the river was eventually sealed off from the rest of the network, and the tunnels have since been secured after a terrorist threat.
Compiled by Dr. Neil Gale, Ph.D.