The group of dignitaries standing by the side of a new and controversial canal watched nervously as two men scrambled over mounds of dirt to reach them. Perhaps the men carried a last-minute injunction to stop the work that was so close to completion. The officials--trustees of the Sanitary District of Chicago--had ordered the hurried opening of the waterway on this date after hearing rumors of such legal maneuvers. But no: The men turned out to be newspaper reporters who had been tipped off that the flow of the Chicago River was about to be reversed.

They were just in time to see a crane claw away the last few feet of frozen earth that separated the river from the canal. With that, the foul river water began to pour into the canal and run west toward Lockport and the Des Plaines River, instead of east toward Lake Michigan. The decades-old problem of keeping the city's drinking water safe had at last been solved.Reversing the Chicago River, polluted with waste and sewage, had long been seen as the best way to end periodic epidemics of waterborne diseases, especially cholera. Such outbreaks occurred when rainstorms pushed river water far into the lake, where cribs collected the city's drinking water. The river had been reversed in 1871, but it had not stayed reversed. A pumping station that emptied river water into the Illinois and Michigan Canal proved inadequate.

Eight years and 8,500 workers had been needed to finish the new 28-mile-long waterway, one of the great engineering feats of its time. In digging the Sanitary and Ship Canal, contractors devised new earthmoving methods and machines, which proved to be invaluable a few years later when the Panama Canal was constructed.

But not everyone was in awe of the canal. Cities along the Des Plaines, Illinois and Mississippi Rivers, especially St. Louis, cringed at the thought of drinking Chicago's sewage. Threats of an injunction by St. Louis caused the trustees to arrange the almost surreptitious opening of the canal.

The spectacle of the westward-flowing river attracted "throngs of people," who, by one account, gathered at bridges and docks to watch "the river current setting briskly upstream instead of lying stagnant as before." Deaths from waterborne diseases plummeted, and towns downstream from Chicago did not suffer.

In later years, the North Shore and Calumet-Sag channels were added to take wastewater from the northern and southern suburbs, and treatment plants were built to clean up sewage before it entered the canals. But during especially heavy storms, the area's rivers still backed up into basements, and occasionally Lake Michigan. Tackling that problem would have to wait another 80 years.