(CN) - The Montana Supreme Court expanded the meaning of "natural" in determining that irrigation permits were required for the Mitchell Slough, a side channel of the Bitterroot River.
The Bitterroot River Protective Association challenged the state's decision not to require irrigation permits, claiming it violated the Natural Streambed Land Preservation Act and the Stream Access Law. The federal court concluded that, because the slough was not considered "natural," it was not subject to permitting or public access.
But the state high court said the judge's interpretation of natural - based on the dictionary definition of "not artificial or manufactured" - was too narrow.
Under the lower court's definition, "precious little water ... could be considered natural," Justice Jim Rice wrote.
"Virtually all of Montana's waters have been altered or manipulated by man," Rice added. If the court allowed "natural" to be defined in the strictest sense, it would lead to the absurd conclusion that no state watercourse would fall under laws designed to affect them.
The Mitchell Slough receives most of its water from a diversionary gate on the Bitterroot River, doubling in flow over its 16-mile course through private property before emptying back into the Bitterroot River. The channel provides irrigation water for human use, and landowners claimed that were it not for return agricultural flows, the slough wouldn't run year-round.
Fishing and recreational groups supported the association's stance on preservation and public access, while cattle interests opposed permitting.
The state high court's reversal will require permits for alteration of the slough and allow for public recreation up to its high-water mark.
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