“If they can dye the river green today, why can’t they dye it blue the other 364 days of the year?”

— Marshal Biggs

The Fugitive (1993)

“Chicago sounds rough to the maker of verse. On comfort we have- Cincinnati sounds worse.”

— Oliver Wendell Holmes, Sr.

The city of Chicago, Illinois, is, of course, famous for its Great Fire of 1871 that destroyed more than three square miles of the city and left more than 100,000 people homeless. The exact cause of the fire is unknown, and the popular story about Mrs. O’Leary’s cow was completely fabricated, and then retracted by the Chicago Tribune immediately after the fire was extinguished. Despite that rapid retraction, the story lives on nearly 150 years later.

A far less serious, but far more expensive disaster befell the city in April of 1993. It involved some bridge repair, old unmapped tunnels, and a massive flood of basements that would close the downtown and the Mercantile Exchange. But most interestingly, many Chicagoans refer to that event not as the “Great Chicago Flood,” but rather as the “Great Chicago Leak” because of the legal wrangling that followed.

The incident began when the Great Lakes Dredge and Dock Company was hired to do repair work on the pilings for the Kinzie Street Bridge. They proposed a specific drilling location for the new pilings, and the city of Chicago approved the location before any work began. What neither the city, nor the company, knew, was that underneath the river, in that exact spot, the long defunct Chicago Tunnel Company had drilled out one of its many interconnecting tunnels to feed the utility lines of the city.

What followed was a comedy of errors. The new piling didn’t actually puncture the tunnel, but it was close enough that over the course of a few days, the flow of water wore through the weakened tunnel wall and allowed a muddy sludge to pour in. Still, no one working on the construction project realized that anything was amiss, because they hadn’t hit the tunnel itself. It was actually a cable television repair man, working inside the old tunnel system who saw the muddy inflow and videotaped it.

The Keystone Cops routine continued, though. Many of the flood gates installed in the tunnels had rusted, ceased to work, or been completed removed. And because the Chicago Tunnel Company had gone bankrupt, there was no one, anywhere, who had any responsibility over them. The tunnels themselves had basically been drilled under private property without any easements, because the building owners were happy to have the utility access that came with them.

And so at first, no one did anything. That is, until the morning of April 13, 1992, when the mud cleared, the wall failed further, and water from the Chicago River began to pour in at a massive rate. In a matter of hours, many of the buildings in downtown Chicago had water in the their basements — some of them with flooding covering several floors of sub-ground building levels. The Chicago Mercantile Exchange reported fish swimming in the basement of its building.

The city still had no idea what was going on until a radio reporter saw that water was swirling near the bridge pilings. The city tried dumping everything they could into the hole — including rocks, dirt and old mattresses. They tried opening the locks on the Chicago River and lowering the water level. Finally, they poured a quick-setting concrete mixture into the tunnels and were able to stop the leak. Much of the downtown was closed for three days and the insurance estimates were that there was close to two billion dollars in damage. And it was those insurance companies that led to legal action, and to the “Great Leak” moniker.

Many insurance policies exempt an “Act of God” from their coverage, and that definition includes floods. As a result, the question of whether insurance companies were going to be on the hook for the two billion dollar price tag turned on whether the incident was a “flood” or a “leak.” The insurance companies, in turn, sought subrogation of those claims against the Great Lakes Dredge and Dock Company. Great Lakes, in turn, claimed that because the leak occurred in the navigable waters of the Chicago River, admiralty law applied. Eventually, the case made it all the way to the United States Supreme Court, which ruled 7-0 in Great Lakes’ favor (with two Justices abstaining).

Flood hatches have now been installed at all places where the tunnels cross the Chicago River, and the City of Chicago has assumed their maintenance. But Chicago’s worst downtown flooding showed us that a flood can be a leak, a bridge piling can be “maritime,” and a cable repair man can be a major city’s hero.