My first thought was: A bomb went off.

An atomic bomb, maybe. Why else would thousands of office workers be evacuating the Loop at midday?

The truth — not that we knew it right away — was far less cataclysmic but in a sense even stranger.

It was noon, and I was getting ready to head downtown for the 2-to-10 p.m. shift as a reporter for the Chicago Sun-Times. I turned on the TV in that pre-Internet era, and the noon news showed workers carrying files, streaming from buildings downtown.

In September 1991, workers aboard a “spud scow” from the Great Lakes Dredge & Dock Company had been on the Chicago River, replacing rotten pilings — those wooden poles driven into the river bottom to protect the foundations of drawbridges from errant boats — at the southeast end of the Kinzie Street bridge.

Putting new pilings exactly where the rotted ones were proved difficult. The bridgetender’s house was in the way. So they moved the new pilings — wooden telephone poles chained together — about a yard south. Just enough of a shift — by a foot, it was later estimated — that it cracked the ceiling of the underground tunnels that crisscross downtown.

The arched tunnels were hand-dug around 1900 by a short-lived telephone company. Seven and a half feet high, six feet wide, they moved freight, coal and ash on small trains. No other American city has a similar system.

Trucks proved more efficient, though, so the train network was abandoned in 1959. The tunnels were largely forgotten.

Phone and cable companies still went down there to run conduits through the passageways, though, and the network was certainly on city plans.

In December, telecom workers noticed water dribbling through the crack and leakage from the river. They reported that to the city in January, with a videotape showing men in thigh-deep water in the tunnel.

The city did what it does so well: nothing. Actually, it inched toward action, putting the repair job out for bid. By later estimates, the repair would have cost $10,000 had it been done in a timely fashion. But it wasn’t.

Water keeps busy even while bureaucracy dawdles, and that morning the crack became a hole the size of an automobile, and the trickle turned into a torrent as the Chicago River began pouring into the 47 miles of tunnel system and into the basements of Loop office buildings and businesses south of the river.

It was Monday, April 13, 1992.

Engineer Jerry Pietras watches as water rises in the basement of a building in the Loop on April 13, 1992. | AP

Before dawn, employees of the Merchandise Mart noticed two inches of water in the basement. They called the fire department. By the time firefighters arrived, that two inches had become two feet, on its way to 38 feet.

“Fish are swimming in the basement of the Mart,” said radio reporter Larry Langford.

Across the river, streetlights went out downtown. In the subway tunnels, water was cascading over open electrical circuit panels, so the CTA cut power to the trains. Electrical units across 24 square blocks of the city were shorting out, basements being a common location for transformers and air-conditioning systems.

Workers drain water from the flagship Marshall Field’s store on State Street in downtown Chicago on April 17, 1992. Field’s was one of 14 buildings with about 25 feet of water in their sub-basements, shutting down the stores. | AP

Three of the six sub-basements at the Marshall Field’s State Street store were completely flooded, and the famous Field’s clock stopped at 7:14. It wouldn’t start again until the day after Labor Day.

The Chicago Board of Trade, the Chicago Board Options Exchange and the Chicago Mercantile Exchange all suspended trading, the effects rippling across the world.

The legal fallout of the flood had lawyers paying $400 a year for the Chicago Tunnel Litigation Reporter.

The First National Bank of Chicago sent traders to its office in London; they didn’t return for three months.

At the County Building, workers scrambled to rescue records, some a century old. With the courts closed at the Daley Center, lawyers raced to the Skokie courthouse to file the first of a lake of lawsuits — so many that, by summer, a pair of industrious Evanstonians would start publishing an eight-page, biweekly Chicago Tunnel Litigation Reporter, charging $400 a year to subscribe.

The destructive torrent didn’t sink the city’s scheduled naming of a new police superintendent, Matt Rodriguez, though never was a top cop appointment more overshadowed.

Loop crime would tumble in the coming weeks because stores were closed and nobody was around to rob, except gawkers looking for evidence of the most subtle disaster ever — a flood in which nobody above ground got wet, a catastrophe without casualties, where damage to property was hidden, in basements submerged, inventory ruined and business lost. But 200 extra police officers were assigned overnight since burglar alarms were without power.

The paper sent me to City Hall. My strongest memory is of crossing Wacker Drive and coming face-to-face with a phalanx of mounted police officers in triangular formation, one rider followed by two followed by three, trotting up the center of Wabash Avenue. Around City Hall, streets were clogged with pumps and dehumidifiers, banks of lights, mobile emergency command centers.

Nobody can ignore a problem like Americans can, but once our face is stuck in a situation, we do assemble the resources.

Not quickly enough, though, for the American Society of Public Administrators, whose national convention, which began that same Monday, brought 12,000 officials to what, until that morning, had been the City That Works. Their seminar — “How Chicago Government Works,” scheduled for that evening at City Hall — had to be scrubbed because the building had no electricity.

Mention the Loop Flood to many Chicagoans today, and the first thing they will mention is mattresses being thrown into the hole in the river at Kinzie Street — a kind of symbol of civic bungling. Some dismiss that as a myth. Others say they were at the scene.

J.J. Madia’s job is to monitor the tunnels for the city of Chicago. | Maria Cardona / Sun-Times

“They brought them, but they never used them,” says J.J. Madia, a civil engineer who for 20 years has monitored the tunnels for the city.

Chicago architect Geoffrey Goldberg, on Daley’s staff at the time, says using mattresses is “not as dumb as it sounds.” He points out that mattresses  were used in World War II as emergency blockage for tears in torpedoed ships.

Workers carry sandbags outside the State of Illinois building on April 14, 1992, to protect against flooding. | AP

Water is pumped out of the lower level of the State of Illinois building on April 15, 1992, as power had been restored  to many of the buildings evacuated during the flooding. | AP

Tuesday, the day after the flood began, dawned with 150 buildings downtown without power. Bellhops used flashlights to guide patrons through the halls of the Palmer House hotel. The lobby of City Hall was half-filled with records rescued from the basement. And Daley fired John LaPlante, his city transportation commissioner, who knew about the leak and had put the fix out for bids.

“I didn’t get the feeling we had an immediate emergency,” LaPlante explained. “If I’d known how serious it was, I would have gone on and done it and taken care of the billing later.”

Seven other city workers also got the axe.

Part of downtown Chicago, seen beyond the skyscrapers, was left dark April 13, 1992 because of flooding in an underground tunnel that runs under the Loop. | AP

The first formal plan — block the break with “pigs,” large inflatable bladders flown in from California — was scuttled due to the “incredible” strength of the current. They couldn’t get the pigs into the tunnels. Instead, caissons were drilled and five-foot pipes lowered through Kinzie Street, down 40 feet and into the tunnel, so it could be plugged. First sandbags, then gravel were poured into one pipe to stop the flow. Then, concrete was poured into the second pipe. Nothing was thrown into the hole itself.

Hoses snake from drains outside  City Hall on April 16, 1992, as pumps worked to drain water from the building’s sub-basements. | AP

On Wednesday, President George H.W. Bush declared downtown Chicago a disaster area.

That afternoon, a crane lowered a diver — former Navy Seal frogman Jim Samoska, owner of Lockport marine contractor — in a steel safety cage to inspect the situation. He emerged to report a temporary plug holding, for the moment, and visibility at six inches.

Diver Jim Samoska is helped out of a lift on April 16, 1992, after surveying work being done to plug a leak in a tunnel under the Chicago River that sent water surging into downtown Chicago. | AP

It also rained — hard. On the plus side, ComEd got power back to all but 14 buildings.

By then, John Kenny Jr. of Kenny Construction was becoming an unflappable fixture on TV, the “Flood Stud,” with his hardhat and just-the-facts-ma’am delivery. Chicagoans peppered him with suggestions for filling the hole, including some who tried to exact payment before sharing their secrets. Kenny said one suggested plugging the hole with Jell-O.

Nearly a year later, John Kenny Jr. stands at the site of the 1992 Loop Flood — the pilings near the Kinzie Street bridge. | Rich Hein / Sun-Times

Entrepreneurs offered dozens of different T-shirts riffing on the same theme: “I Survived the Loop Flood.”

Workers begin to dig a connection between the water-filled freight tunnel and a lower tunnel beneath Jefferson and Monroe streets on April 14, 1992, to drain the flooded tunnel. | AP

The Metropolitan Pier and Exposition Authority offered 60,000 square feet of office space at McCormick Place, with phones, for a month to any business that needed it. The IRS gave an automatic week’s extension to affected taxpayers who wrote “Chicago flood” across the front of their returns.

Anna Pesole made national news by picking up her wedding dress at an otherwise-shuttered Field’s, where mannequins were posed in the windows with mops and buckets.

For the week after the flood, my job was to monitor the hole — a task I approached by hanging out at the bar of the nearby East Bank Club, venturing out every hour to take a gander at the progress, which was slow.

The problem took months to rectify. Gery Chico, the mayor’s deputy chief of staff, was in charge of emptying the water from the flooded tunnels and basements.

“Where are you going to put it? How are you going to get it out of there?” says Chico, now an attorney with Chico & Nunes. “We wound up doing it with huge generators and pumps to take water out. Most of it went into the Deep Tunnel system. We had to create new manholes. You’ll still see, on the streets of Chicago, manholes made for the purpose of dropping huge pipes into the system to get the water out.”

The Army Corps of Engineers finished its work May 21, having pumped 134 million gallons of water out of the basements of businesses. A number of Chicagoans filling tax returns late forgot to write “Chicago flood” across their tax forms as instructed, and their extensions were initially denied.

Also that May, Chicago floated $160 million in bonds for viaduct and street improvements. A year later, Daley announced twice-monthly inspections and a “computerized atlas” of buried utility lines. According to the Chicagoland Chamber of Commerce, 75 of the 8,000 businesses never reopened. Overall costs of what became known as the Great Loop Flood were pegged at $1.95 billion. The city installed a series of 2½-inch-thick steel waterproof doors to seal off the tunnels that run under the river.

The legal aftermath flowed on long after the last basement was dry. Nearly 500 lawsuits were filed in state court. Among them was one by Universal Recording Studios that demanded millions, claiming that the flood destroyed irreplaceable original master recordings of singer Vic Damone.

The tunnel as it looks today below City Hall. | Maria Cardona / Sun-Times

The city ended up paying about $50 million in damages.

Great Lakes Dredge & Dock, a venerable Chicago company that helped prepare the land for the 1893 Columbian Exposition, sued the city, saying it had reported its repositioning of the pilings and received spoken approval. That still doesn’t fly for some.

“They didn’t do their homework; they didn’t look at the drawings,” says Goldberg, son of famed Chicago architect Bertrand Goldberg.

The company tried to push the lawsuits it faced into Admiralty Court — an arcane jurisdiction where its liability would be limited to the cost of the barge and the tug that maneuvered it. The case went all the way to the U.S. Supreme Court. Lawrence E. Rosenthal, a deputy corporation counsel for the city, argued that Great Lakes Dredge & Dock was asking the justices “to bring admiralty law into the basement of Marshall Field’s.”

Seven justices felt that’s exactly where it belonged. And the company ended up escaping liability.

The case of “Jerome B. Grubert v. Great Lakes Dock & Dredge” became a landmark ruling, featured in textbooks and classrooms.

Randall Schmidt spends two weeks in his law school class on the Loop flood case. | University of Chicago

“It’s a very important case,” says Randall Schmidt, a University of Chicago Law School professor. “What Grubart did is, basically, clarified what’s required for admiralty jurisdiction. It still provides the basic framework in tort cases.”

Schmidt spends two weeks each semester in class on Grubert.

“It’s a very bizarre case,” he says. “If I were an admiralty law professor making up exam questions, this would a perfect exam question.”

And so it remains, a strange chapter of Chicago history, a watery bookend to the Great Chicago Fire that some don’t know about or have forgotten — and something the city has been vigilant to avoid a happening again.

“There are a number of takeaways from the flood,” says Dan Burke, chief engineer for the city Department of Transportation. “You had to recognize the importance of the tunnel system, both as an asset and a liability. You have to commit people, resources, time to properly maintaining it.”

Madia’s title is “Civil Engineer V,” but he calls himself “project manager for the tunnels.” For two decades now, he’s been responsible for every inch of the 38 remaining miles of tunnels, lined with telecom conduits, the ground muddy, the tracks still in place, often covered with three inches of water.

“That rumble you’re hearing is the CTA going directly over the top of the tunnel,” Madia says, giving a tour.

J.J. Madia has walked these tunnels for two decades. | Maria Cardona / Sun-Times

Delicate, two-foot-long calcium stalactites hang from the tunnel ceiling, and drops of condensation glitter like diamonds in flashlight beams. The maze of branching tunnels is well marked, with standard green Chicago street signs down there that correspond to the roads 40 feet above. No one builds close to the tunnels without submitting their plans to Madia. Monitoring the tunnels is his full-time job.

Burke says that, with the rise of the internet, the tunnels “have gone through a renaissance since the flood. They’ve reverted back to their original purpose, as a telecom corridor. They are the fiber communications backbone of the central business district.”

Goldberg bristles that the flood is generally remembered as a moment of epic city bungling. He thinks the fast, coordinated effort after the flood had the “the crispness of a well-turned double-play” in baseball and should be recognized too. Others who worked on the problem agree.

“I don’t know if you’re ever proud of disasters” said Chico “It’s really how you respond to these things that define who you are. The city responded very admirably.”

Some Chicagoans commemorated the flood in verse. The tribute that Irving A. Benjamin typed out on April 20, 1992, remains all too relevant today, ending:

For the infrastructure’s rotting and nothing’s been done.
No money at hand—we’re under the gun

Bridges are falling. Sewers rotting too,
Waterlines failing, what can we do?

Pressure the gov, the pres and the mayor
Find some money — we need a payor.

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