The Obama administration is ordering an ambitious cleanup of the Chicago River, a dramatic step toward improving an urban waterway treated for more than a century as little more than an industrialized sewage canal.

In a letter obtained Wednesday by the Tribune, the U.S. Environmental Protection Agency demands that stretches of the river must be clean enough for "recreation in and on the water," a legal term for recreational activities including swimming and canoeing. The order also applies to two connected waterways, the Cal-Sag Channel and Little Calumet River.

If state officials fail to adopt more stringent water quality standards, the "EPA will promptly do so itself" by invoking its authority under the federal Clean Water Act, the agency's top water official told Lisa Bonnett, interim director of the Illinois EPA.

"A decade of investments in walkways, boat ramps and parks have provided people with access to the water," Susan Hedman, the U.S. EPA's regional administrator, said in a statement. "And now we need to make sure the water is safe."

Federal officials have been suggesting the river improvements for more than a year but took more aggressive action because they believed state regulators haven't gone far enough. Complying with the order likely will require more expensive sewer bills in Chicago and the Cook County suburbs, where homeowners and businesses pay among the nation's lowest costs for treating human and industrial waste.

The EPA's action was welcomed by Mayor-elect Rahm Emanuel.

"By making its waters safe and clean, we can restore the river as a center for recreation and unlock its full potential to enhance Chicagoans' quality of life," said Tarrah Cooper, an Emanuel spokesman. "The mayor-elect supports the goals for improvement outlined by the (EPA) and looks forward to seeing the plan that the Metropolitan Water Reclamation District will put forward to meet them."

The EPA's nine-page order goes far beyond standards adopted last year by the Illinois Pollution Control Board, a state rule-making panel. The state's plan limits disease-causing bacteria in the river, but only to a point considered safe enough for paddlers and boaters who briefly fall into the water.

What the Obama administration is envisioning sets the bar higher. As a result, two of the Chicago-area's massive sewage-treatment plants would need to be overhauled to disinfect partially treated human and industrial waste that churns endlessly into the waterways.

Chicago is the only major U.S. city that skips that important germ-killing step. Until now, the river and its connected waterways have been exempt from the toughest provisions of the Clean Water Act because it was long assumed that people wouldn't want to come near the fetid channels.

The Metropolitan Water Reclamation District, an independent agency that oversees the Chicago-area waterways and operates local sewage-treatment plants, has steadfastly opposed tougher water quality standards.

A district spokeswoman declined to comment pending review of the U.S. EPA letter. Last year, after the Tribune first reported on the Obama administration's efforts, two of the district's top officials said it would be a waste of money to clean up the river. Making the river safe enough for swimming, they said, would put children at risk of drowning.

The district estimates it would cost up to $1 billion to disinfect wastewater from its treatment plants. The U.S. EPA commissioned its own study that concluded the cost would be considerably less — about $242 million, or about $2 a month per household spread out over two decades.

Based on the EPA's new letter, the improvements could be even less expensive. The order applies to stretches of the Chicago River downstream from the North Side Treatment Plant at Howard Street and McCormick Boulevard to Bubbly Creek near Ashland and Archer avenues, and to the Cal-Sag Channel and Little Calumet River mostly downstream from the Calumet Treatment Plant.

However, the federal order won't require disinfection equipment at the district's biggest treatment plant in Stickney along the heavily industrialized Sanitary and Ship Canal. Surveys show steady recreation on the stretches covered by the order, but not near the Stickney plant.

More than two decades of improvements have steadily turned the Chicago River into a sort of second lakefront. Most, if not all, of the river's murky flow is partially treated sewage, but some stretches are clean enough to draw kayakers to the channels and restaurants and housing developments along the banks.

"We've got a chance for our generation to do something big for this important river," said U.S. Sen. Dick Durbin, who vowed to help local officials secure federal funding for improvements.

Lawyers for the state, industry and environmental groups have fiercely debated the river's future for most of the last decade. Five years of study and three years of hearings echo similar efforts in Boston, Cleveland, Los Angeles, New York and other cities that are turning polluted waterways into civic amenities.

In a statement Wednesday, Bonnett said the state EPA is pushing for the district's sewage-treatment plants to be upgraded with disinfection equipment within three years.

The letter from federal officials calls for the river cleanup to be completed "as soon as possible."

The order comes as lawyers for the U.S. EPA, state and district hammer out a legal deal to prevent raw sewage from pouring into the waterways during rainstorms. A draft agreement calls for more specific deadlines to finish the Deep Tunnel project, a labyrinth of giant sewer pipes and huge reservoirs designed to store sewage and runoff until it can be treated.

mhawthorne@tribune.com

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