(CN) - The nation's high court on Monday refused to disturb a lower court's ruling that the transfer of polluted water from one body of water to another doesn't violate the Clean Water Act.
In June 2009, the federal appeals court in Atlanta allowed the Southern Florida Water Management District to pump agricultural runoff into Lake Okeechobee in southern Florida without a permit.
Environmental groups, including the Friends of the Everglades and the Miccosukee Tribe, said the pumping violated the Clean Water Act, but the 11th Circuit said a regulation recently issued by the Environmental Protection Agency changed that.
The new regulation interpreted the phrase "navigable waters" in the Act's ban on adding pollutants to "navigable waters from any point source" to mean all bodies of water within the United States.
This so-called "unitary waters theory" meant that pollutants could be transferred from one body of water to another without requiring a permit.
Friends of the Everglades said the regulation didn't match the goals of the Clean Water Act and would result in "horrible hypotheticals," including the pumping of the most polluted water in the country into the most pristine lake.
But the 11th Circuit deferred to the EPA's interpretation, calling it "reasonable and therefore permissible."
The Supreme Court left that ruling intact by deciding not to hear the environmentalists' appeal.
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