"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.'  "

Michael Hawthorne reports for the Chicago Tribune May 12, 2011. [2]