By contrast, for decades the Chicago River was a source of revulsion rather than inspiration. For many years, Chicago was the only major American city to dump partially treated sewage into a major waterway. The river also was a waste bin for everyday trash and factory chemicals. Today, it's vastly cleaner than it was before, thanks in part to the Deep Tunnel project that greatly reduced the amount of raw sewage pumped into the river. You still can't swim in it, but you can walk alongside it without wincing at the odor.