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43 U.S. Code § 390dd - Limitation on ownership

Except as provided in section 390ii of this title, irrigation water may not be delivered to—
(1)
a qualified recipient for use in the irrigation of lands owned by such qualified recipient in excess of nine hundred and sixty acres of class I lands or the equivalent thereof; or
(2)
a limited recipient for the use in the irrigation of lands owned by such limited recipient in excess of six hundred and forty acres of class I lands or the equivalent thereof;
whether situated in one or more districts.