Opinion summary
Etalia.ai summary of the majority opinion
The case involved a dispute between the states of Michigan and Illinois regarding water diversion from Lake Michigan through the Chicago Sanitary and Ship Canal. The Supreme Court was asked to determine whether Illinois' actions violated previous decrees that limited such diversions to protect downstream water levels in other Great Lakes states, including Michigan. The court examined historical agreements and prior rulings concerning interstate water rights, focusing on maintaining equitable apportionment among affected states while balancing environmental concerns with economic development needs. Ultimately, the decision reaffirmed existing limitations on Illinois’ ability to divert waters from Lake Michigan without exceeding agreed-upon limits or causing harm to neighboring jurisdictions.
Opinion of the Court
Decided 29 Jun 1959 · Official report