State of Wisconsin v. State of Illinois and Sanitary District of Chicago
Headline: Court temporarily allows diversion of Great Lakes water into the Illinois Waterway and Mississippi to ease low-water navigation, permitting up to 8,500 cubic feet per second under Army Corps control through January 31, 1957.
Holding: The Court temporarily modified its 1930 decree to permit the Army Corps to divert up to an average of 8,500 cubic feet per second from the Great Lakes into the Illinois Waterway and Mississippi through January 31, 1957.
- Allows Army Corps to divert up to 8,500 cubic feet per second.
- Eases navigation on the Mississippi River during the low-water emergency.
- Requires diversions not to seriously interfere with Illinois Waterway navigation.
Summary
Background
A group of States (including Wisconsin, Minnesota, Ohio, Pennsylvania, Michigan, and New York) brought these cases against the State of Illinois and the Metropolitan Sanitary District of Greater Chicago. Several other States intervened (including Missouri, Kentucky, Tennessee, Louisiana, Mississippi, Arkansas, and Iowa). The dispute rests on a decree the Court entered on April 21, 1930, and arises from an emergency caused by unusually low water in the Mississippi River that threatens navigation.
Reasoning
The Court considered whether to temporarily change Paragraph 3 of the 1930 decree to allow water to be diverted from the Great Lakes–St. Lawrence System into the Illinois Waterway and the Mississippi River. The Court issued a temporary modification allowing, through January 31, 1957, a diversion not exceeding an average of 8,500 cubic feet per second, in addition to ordinary domestic pumpage. The Army Corps of Engineers is authorized to decide the times and amounts of diversion that will help navigation without seriously interfering with navigation on the Illinois Waterway. The order explicitly preserves the parties’ legal rights about any other diversions.
Real world impact
Practically, the Army Corps may move a set amount of Great Lakes water to aid ships on the low Mississippi. The change is temporary and limited to the stated amount and period, so the older 1930 decree will resume in full effect after January 31, 1957 unless the Court orders otherwise. The order aims to help navigation now while leaving legal questions about other diversions open for later resolution.
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