Harlan F. Stone

“ We leave undecided the question whether an equitable division of the unappropriated water of the river can be decreed in a suit in which the United States and the interested states are parties. Arizona will be free to assert such rights as she may have acquired, whether under the Boulder Canyon Project Act and California's undertaking to restrict her own use of the water or otherwise, and to challenge, in any appropriate judicial proceeding, any act of the Secretary of the Interior or others, either states or individuals, injurious to it and in excess of their lawful authority. ”

“ Arizona, by her proposed bill of complaint, asserts no right arising from her own appropriation of the waters of the Colorado river. No infringement of her rights acquired by appropriation is alleged, and no relief for their protection is prayed. While it is alleged that definite plans have been made for the irrigation of 1,000,000 acres of unirrigated land in Arizona, and a right to share in the water for that purpose is asserted, it does not appear that any initial step toward appropriation of water for such a project has been taken. ”

“ The appropriator first in time is prior in right over others upon the same stream, and the right, when perfected by use, is deemed effective from the time the purpose to make the appropriation is definitely formed and actual work upon the project is begun, or from the time statutory requirements of notice of the proposed appropriation are complied with, provided the work is carried to completion and the water is applied to a beneficial use with reasonable diligence. See Arizona v. California, supra ”