The Chicago River used to flow into Lake Michigan.  But since raw sewage from the City of Chicago flowed into the river and then Lake Michigan, the city’s drinking water was often contaminated.  Thus, in 1892 a major civil engineering project began–reversing the flow of the Chicago River into the Mississippi River by constructing a 28-mile canal to the Des Plaines River which flows into the Mississippi.  Needless to say this did not make the residents of St. Louis happy, who became the recipient of the raw sewage.   Law students and public nuisance buffs know of the Supreme Court case Missouri v. Illinois (200 U.S. 496 (1906)).

While many have suggested that the the flow of the Chicago River be returned to Lake Michigan, now a century later, lame duck Mayor Daley has offered his “heavyweight” support for the idea.  See here.