On the morning of April 13, 1992 most of the buildings in the Loop were flooded and lost electricity. It all started when several companies wanted to run mini-cruise ships on Lake Michigan and moor them in the Chicago River. Contractors to were sent to pull out the old pilings and put new pilings in the exact same spot. (A piling is a bunch of telephone poles bundled together that are used protect bridges.) The contractors decided that it was too much trouble to pull out the old ones and just drove the new pilings right next to them. At the bend in the river next to the Merchandise Mart, workers punched a hole and flooded an old freight tunnel. This tunnel was part of a vast network of railway tunnels that provided freight service to every block in the Loop area. These tunnels had been abandoned since 1959.
550 gallons of water were flowing into the tunnels every minute. It seeped from the tunnels and flooded most of the buildings downtown. Water was spilling out the doors of City Hall and onto the street. Someone caught a fish in the basement of the State of Illinois Building. By 10:00 am most of downtown had lost power and had to be evacuated. People had to walk down stairs to get out of their office buildings, many were trapped in elevators. Sixty-five truckloads of gravel and concrete were brought in and dumped in the river in an effort to stop the water from pouring under the Loop. The city even began dropping mattresses in the whirlpool in the hopes they would block the hole and soak up water. The Army Corps of Engineers were brought in to help out. A total of 124 million gallons of water had flooded the tunnels and they were not fully drained until April 25.
All of Chicago's central commercial district was without power and shut down for three days. Several works stored in the basement of the Art Institute were damaged. The total cost of the flood was estimated at 1.95 billion dollars.
This was also the day my little sister was born. My Dad wanted to name her Flo in honor of the flood. My mother quickly put a stop to that. :p