All the sewage still flowed into the Chicago River. Desperate to protect residents from waterborne scourges like cholera, city leaders at the end of the 19th century hatched another audacious plan: Reverse the direction of the river so it flowed away from Lake Michigan instead of into it.
They achieved this by dynamiting a mile-long canal connecting the Chicago River to the Des Plaines River, which flows toward the Mississippi. The Chicago River passes through the heart of the city. But is river the right word? Designed as an immense drain to flush away wastewater, it runs as straight as an interstate highway. It can flow in both directions. Today, Chicago is still fighting to put water in its place.
An expanding network of vast lagoons captures sewer overflows that plague the city. The Chicago Sanitary and Ship Canal opened in , a feat of engineering feet wide and 25 feet deep and, importantly, lower than Lake Michigan. So gravity dictated that the Chicago River would henceforth flow in the opposite direction. Today, on the Chicago waterfront stands the Harbor Lock, a set of mammoth steel gates separating lake water from river water. Chicago has, essentially, fashioned for itself a manmade continental divide, with hinges.
For most of the years since it opened, the river and canal, the centerpiece of the city's huge manmade waterway system, functioned just as its designers had hoped. But in the heaviest storms, even the river and canal system could get overwhelmed. Which left two bad choices: Let the river and canal overtop their banks and flood city streets with sewage, or open the lock gates so the swollen, polluted river could again, albeit temporarily, tumble into Lake Michigan.
Since the s, Chicago has been constructing a multibillion-dollar system of sewage-storage tunnels and reservoirs. The idea is that, when rainstorms hit, the extra runoff can be safely warehoused. Once a storm subsides, all that storm water and raw sewage can be slowly treated and released, avoiding floods and also avoiding the release of untreated filth into the lake. The tunnels, some a yawning 33 feet in diameter and running up to feet below city streets, stretch miles and collectively hold 2.
How big is that? To help soak up downpours, open spaces are also being built, as well as green roofs and porous parking lots. This forces Chicago to continue to rely on opening the navigation lock, along with some nearby gates, as a safety valve to send pulses of storm-driven wastewater into Lake Michigan.
In this way, Lake Michigan has been there to rescue Chicago in its most dire times of need. That afternoon Tyrone Valley , lockmaster at Chicago Harbor, got a call. There was big trouble brewing in the river. Valley, 56 years old, had just worked an overnight shift at the lock, and he was looking forward to having the week off. But his crew needed him back because the rains that had been pounding the city for three days were threatening Chicago in a fashion no one had experienced.
He hopped into his red Ford F and started the hourlong drive back from his home in Joliet yes, named after that Joliet. Along the way, his crew called him with alarming updates: Water was rising menacingly fast against the riverbanks in the heart of Chicago. Valley recalled. That trigger is typically 3. Valley had headed home that morning. Three days earlier, a relentless storm had dropped a record hour rainfall for that date.
The tunnels and reservoirs had done their job helping to contain the deluge. But then, a second storm hit while the reservoirs were still holding water from the first storm. That meant the storm water and sewage had to be released straight to the river. And it was too much for the river to handle. By p. Messy, yes. But not as messy as letting sewage-laced water pour into downtown. At p. At that moment, Mr. Valley was standing along the lock wall, helpless.
Then, at p. Finally, Mr. Valley had options again. He gave the order, and his crew opened the immense steel lock gates. A whoosh of water carrying all manner of waste — trees, chunks of dock, litter, toilet flushes — blasted into Lake Michigan. In mere minutes, the suddenly reversed river, roaring like a freight train, dropped below lake level. This was a new problem; If the gates stayed open, lake water would slosh back into the river, further flooding the city. There was nothing in the playbook for this scenario.
Valley and the lock operators had to wing it, pinching the gates closed to let the river again rise above the lake, then swinging them open again to let the swollen river drain into the lake. Again and again, the crew repeated these steps.
They were, almost literally, bailing out a flooding downtown Chicago by flapping the steel gates. Still, it was not enough. A city hotline fielded more than 1, distress calls from residents whose basements were flooded. It showed the lake was roughly nine feet higher than its modern long-term average. That was during a post-glacial period, hydrologists point out, when the lake was seeking a steady state.
Changing weather patterns hint that it still is. Six months after the flood, Mr. Valley and Joel Schmidt, an Army Corps hydraulic engineer, stood on the steel deck above the lock gates and looked down as Lake Michigan splashed against them.
If a two-foot storm surge were to strike when the lake level was just a couple of feet higher, the lock itself would in effect be useless. Lake water would overtop its gates and race into the city, and beyond.
Schmidt said as waves crashed nearby. Cheryl Watson remembers the basement of her brick bungalow on the South Side as a place to play ping pong, to roller skate and, when it rained, to fear. Two Chicago police officers were shot and injured — apparently by one bullet — on Wednesday night after a third officer accidentally discharged his handgun during a struggle with a man while investigating a homicide, officials said.
The officer fired his weapon once, and one officer was struck in the arm and another in the shoulder, David Brown, superintendent of the Chicago Police Department, said during a news conference. The three officers were not immediately identified. The episode began around p. By Glenn Thrush and Michael Crowley. By Julia Jacobs and Robert Chiarito.
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