Chicago was once too flat to drain its sewage, so engineers raised entire streets by four to five feet and jacked buildings up to match — one 320-foot block of shops was lifted four feet on 6,000 screws while businesses inside stayed open

In March 1860, six hundred men climbed into trenches beneath a Chicago city block and waited for a signal.

Above them sat 320 feet of shops, offices, a printworks and a marble bank, four and five storeys high, weighing around 35,000 tons. Every business inside was open. Each man had eight or ten jackscrews to himself, and on the signal he gave each one a quarter turn, walked his line, and started again. It rose about a foot a day.

Why a flat city could not flush

Chicago’s problem was elevation. The ground sat barely above the surface of Lake Michigan, so rainwater and waste had nowhere to run. It pooled and stayed.

That was measured in bodies. Cholera killed 678 people in 1849, and WTTW’s history of the city’s public health engineering records more than 1,400 deaths in the 1854 outbreak. Six straight years of cholera and dysentery pushed the state legislature into creating a Board of Sewerage Commissioners in February 1855. As the Chicago Public Library’s finding aid for its sewers collection sets out, first mayor William Ogden chaired it and brought in Boston engineer Ellis Chesbrough to design the country’s first comprehensive underground sewer network.

Chesbrough got a long way into that job before running into the arithmetic. Sewers work on gravity, and gravity needs a slope. Chicago had none to offer. His answer was to stop digging down: lay the pipes at street level, bury them under fill, and pave a new road on top, six to ten feet above the old one.

The grade nobody wanted to pay for

The commissioners balked. There might not be enough soil within reach to bury a city that deep, and every shopfront would end up with its ground floor below the new footpath, at the owner’s expense. As documented by Chicago Architecture History, the board judged that bill politically unacceptable and sent the Common Council a lower compromise grade, one that most existing front steps could absorb.

That still left plenty of buildings four or five feet below the street. Owners could rebuild, move out, or go up.

Two hundred screws and a large brick building

Enough of them chose up that a whole trade appeared. Their method was blunt and clever at once: expose the foundations, thread heavy timbers called needles through the walls, seat a jackscrew under each one, then turn every screw a matching fraction, all at once, so the load never shifted onto one corner.

January 1858 brought the first masonry test, at the corner of Randolph and Dearborn. A four storey, seventy foot brick block weighing about 750 tons went up six feet two inches, on roughly two hundred screws, under a Boston contractor named James Brown. The Chicago Daily Tribune reported that the building came through undamaged. More than fifty comparable lifts followed that year.

Five days in March

Lake Street was the showpiece. Three firms split the front between Clark and LaSalle for a combined $17,000, and the primary reports gathered in this archive of Chicago Press and Tribune coverage record the outcome: four feet eight inches of lift in five days on six thousand screws, with a signalling system keeping the turns synchronised.

Hanging the footpaths was the commercial masterstroke. Contractors fixed them to the buildings themselves and carried them up in step, so nobody shopping in the drapers or the drug store stepped down into a building site. Trade actually improved, the paper noted, because people came to gawk. Not a pane of glass broken, and no cracked masonry.

On the final day, crowds were let into the basement to walk around underneath, among what one reporter called a forest of iron screws.

The man who left for the railways

One of the three contractors was George Pullman, then in his late twenties, who had cut his teeth lifting the Matteson House hotel in 1859. In 1861 he joined the firm of Ely and Smith to raise the Tremont House, six storeys and an acre of floor, lifting it a full six feet on five thousand screws while the hotel kept taking bookings. A Scottish traveller, David Macrae, later recorded a guest’s account: the front steps seemed to grow steeper each day, and windows that had been at eye level on arrival sat above his head by checkout.

Pullman’s own interest in screws did not last. Per the Northern Illinois University Digital Library, lifting work was drying up by the mid 1860s, and he took his carpentry into railway sleeping cars, which is what his name ended up on.

His trade outlived his attention to it. Chicago’s papers noted in 1860 that New Orleans was reportedly weighing the same treatment, and that the city was training the men who would do it.