How Hidden Connections Nearly Sank Chicago

One morning in 1992, a Chicago radio reporter looked into the river and, stunned, told listeners he saw “swirling water that looks like a giant drain … I think someone should wake up the mayor!” The water was rushing into a 60-mile network of underground railroad tunnels that had been secretly dug beneath the city in the 1800’s and then forgotten, until a construction crew accidentally punctured one tunnel under the riverbed. What followed was one of the costliest floods in the city’s history. Fish swam in skyscraper basements. The entire financial district had to be evacuated. Richard Powers remembers the story. [%comments]


"underground railroad tunnels that had been secretly dug"

They were hardly dug secretly. Those who dug the tunnels were aware of them. The companies that operated in them were aware of them. The customers who shipped via these tunnels were aware of them. The city authorized them, was aware of them and inspected them regularly (but not adequately). They were by no means secret.


I liked this line: "dumping sixty-five truckloads of rock, cement and mattresses into the now-gaping hole..."
Mattresses, really? Did they test that with the blue fluid often seen in a certain type of commercial?


In an interesting epilogue to this posting, construction crews were filling some of these tunnels with concrete and ruptured the main highway into and out of downtown Chicago.

So even 17 years later, the tunnels are causing problems. :-)


Plugging a big hole full of moving water from the upstream end isn't easy. Theoretically you initially put stuff in that is big enough to not get carried away by the water (I doubt the mattresses worked). The big stuff won't plug the hole at all but will turn it into a bunch of smaller holes into which you can then start dumping slightly smaller stuff. Eventually you get the flow slowed down enough that you can do something permanent without having to worry about it washing away before it is finished.

I think the company that ended up successfully fixing it did so by driving a lot of piles completely through the tunnel nearby on both sides of the hole to form a kind of cage surrounding the hole to trap the stuff they were dumping in from the river. Once the cage filled up with whatever junk they were throwing in there they were able to dump gravel and sand to further slow down the flow without anything washing away. Then they pumped concrete in until the entire thing was plugged solid.



Dear Chicagoans,

You have a very lovely city, an excellent history filled wonderland with crime, credentials and charisma. The best in America. Quite amazing if you are an urban dweller. I look at you from 30 miles away nearly everyday where you look so small resting on the lake's big shoulders.

In indiana we are backwards. I love it because i am quite backwards.

For instance:

We are unpaving paradise and taking away parking lots.

oooh wop wop wop

sliced from a article in our local tribune:

The first phase, completed last year, removed the auxiliary parking lot east of the main lot, winning the Governor's Award for Environmental Excellence and similar recognition by Chicago Wilderness and the Association of Conservation Engineers.

The success of the project in restoring the creek's natural character is being monitored by the DNR's Hoosier Riverwatch program.

"The Dunes Creek Project is a great example of how restoration can support local jobs and improve our environment," said James Balsiger, acting administrator of NOAA's National Marine Fisheries Service.

The public will be able to observe progress on the project through the "Dunes Recovery Cam," a live camera to be installed on the pavilion roof that will upload images to the Web every 15 minutes. The camera will be available online beginning next week at .



I lived in Chicago when the flood occured. My wife worked in a bank on LaSalle. She had not idea about the flood until I called her and told her what I was seeing on TV.
The downtown evacuated with relative calm and efficiency. The trains ran unscheduled trains out of the downtown all morning.
That night I went down to the river near where the hole was just to look around. I ended up looking at blue prints for the underground tunnels on the hood of a police car with a bunch of engineers and fireman.
They did dump mattresses into the river to try and clog up the hole. Also rocks, boulders, and cement.
It was pretty crazy.
My wifes bank was closed the next day because they had not electricity or water. When they did open, they still did not have water. The employees had to walk down to the street and use port a potties that were set up on LaSalle. About a month later to thank the emploees for working during the flood, the bank gave each employee a key chain with a small flipper on it. The flipper had the words "Chicago Flood Survivor".