Hard to imagine now, but swimming marathons in the Chicago River were popular early in the 20th century. Reversing the river’s flow in 1900 had cleaned up the water, and shipping had declined, clearing space for swimmers.

But in subsequent years, so much sewage, industrial waste and other pollutants fouled the river that when Mayor Richard J. Daley said in 1973 he hoped Loop workers could someday fish in the river on their lunch hours, experts laughed. So did we.

EDITORIAL

This was a river, after all, whose South Fork on its South Branch was nicknamed Bubbly Creek because of the gases still bubbling from decaying offal flung into the water by giant meatpacking companies. A river that some people viewed only as a highway for barges and an open sewer.

Fortunately, we’ve come a long way since 1973, to the point that, as Dale Bowman reports in Sunday’s Sun-Times, the river might be safe enough to swim in well before the official goal of 2030. Let’s celebrate that news — and keep the pressure on to get the job done.

Already, enthusiasts have made a splash along the Chicago Area Waterway System, of which the river is a part. You might have seen them last year taking an afternoon dip in the Cal-Sag Channel, which until recently was so polluted the Metropolitan Water Reclamation District warned people not to even touch the water.

The Cal-Sag is a lot cleaner because the huge Thornton Quarry reservoir opened in 2015. It holds up to nearly 8 billion gallons of combined stormwater and sewage that used to go straight into the waterways. Now, the reservoir keeps the water back until it can be treated.

The MWRD’s Deep Tunnel project, the first phase of which was completed in 2006, stores stormwater and sewage throughout the Chicago area so it can be treated before it is released. In 2015 and 2016, the MWRD also began disinfecting water from two of its plants to remove pathogens before the wastewater is released.

As a result, kayakers now paddle the entire length of the river, as you can see from the newly completed 1.25-mile Riverwalk through downtown. And the water is clean enough for swimming — on most days. But heavy rains can still overwhelm the system, triggering the release of untreated stormwater and sewage into the river and, if the locks are opened, into the lake.

We still have a ways to go to make the river truly swimmable. For example, the Deep Tunnel’s second phase, which includes an even bigger reservoir in McCook, isn’t scheduled for completion of its final phase until 2029. Areas where odor is a problem could benefit from aeration stations. Much more work needs to be done to retain water upstream so heavy rains don’t overwhelm the system. Eventually, the MWRD needs to find ways to keep road salt out of the waterways and upgrade its infrastructure to keep pace with stronger storms expected as a result of climate change.

Swimmers need more than protection from pollution. They also need a way to get in and out of the water. Now much of the river’s shores are lined with walls or steep banks, and there are few ladders. That’s a safety concern — no easy way out — on a river that’s 10 to 25 feet deep in most places.

Swimmers also need a place to swim in the river without fear of being hit by passing boats. As Sun-Times columnist Mark Brown pointed out last summer, the increasing number of commercial, pleasure and recreational watercraft already is raising safety concerns without adding swimmers to the mix.

Last week at the 2017 Chicago River Summit, experts discussed ways to improve the river. And this week, Mayor Rahm Emanuel will host 17 mayors from around the world to discuss the future of urban waterways and Chicago’s plans to increase recreational activities on the river, including better access.

But in Washington, which has provided much of the funding for Chicago area water quality improvements, the current is running in the wrong direction. The Trump administration is considering major cuts to the U.S. Environmental Protection Agency, and is proposing a 97 percent cut in funding for Great Lakes restoration. Clean water does not appear to be a priority.

In Chicago, we’re used to going against the flow. There’s no reason to give up on the goal of a swimmable river.

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