The video thumbnail image shows a black and white bridge over blue water. Blue arrows show that the flow of the water was switched from one direction to the other.

Why the Chicago River was reversed

It used to be treated more like a sewer than an ecosystem.
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Transcript

This is the story of how the Chicago River went from being used as a sewer to serving as a thriving ecosystem. Josh: After the big population boom of Chicago. So think of 1833, when the Chicago region had maybe 400 to 500 people. It was once a flourishing, gorgeous, pristine prairieland with a river running through it. And then fast-forward 30 years to 1860s, when there was over 120,000. That is a huge population increase. And whenever a population increase happens next to a waterway, usually that waterway is negatively impacted. So that meandering prairie stream, it was not great for bigger boats and high populations of transportation. So it was manipulated by people, it was deepened, it was widen, it was straightened. The Chicago River connects to Lake Michigan, which supplies all the drinking water for the region. And in the 1800s the river was commonly used for sewage and garbage disposal. People didn’t understand the effect this would have on the lake. But the pollution from the river was causing contamination of the drinking water. Water cribs were installed in 1867. These big pumping stations allowed drinking water to be collected away from the pollution. But eventually, changing currents caused these cribs to be contaminated too. The city knew a better solution was needed. Josh: How do we basically prevent our polluted Chicago River, the river that we have polluted, from even accessing Lake Michigan, which is our drinking water, at all? And the way people did that was by digging a canal between the Chicago River and the Des Plaines River. The western side was dug deeper, so when the canal was opened, water would flow in the opposite direction because of gravity, eventually pulling the entire system in the opposite direction. So the flow of the Chicago River was reversed to safeguard the drinking water supply. That still didn’t fix the river, though. Another problem for the river—and rivers in cities all around the world—is runoff from streets. But since the 1970s, groups have been working to restore the health of the Chicago River. Josh: You don't have to be from Chicago to understand this story, because, no matter where people are from, they probably rely on a water source. Some sort of lake or river or ocean or shoreline—they can kind of take the story of Chicago and think, How do I respect the water that is where I live?

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