Idaho Code § 42-2701
Whenever the United States shall, through its proper officers, authorize the construction of any irrigation works in this state under the provisions of the Reclamation Act of June 17, 1902, no lands belonging to the state whose irrigation depends upon the construction of such works shall, after such authorization for construction shall have been publicly announced or communicated by such proper officer to the governor of the state, be sold except in conformity with the classification of farm units by the United States, and the title to such lands shall not pass from the state, until the applicant therefor shall have fully complied with the provisions of the laws of the United States, and the regulations thereunder, concerning the acquisition of the right to use water from such works, and shall produce the evidence thereof duly issued.
Idaho Code § 42-2701