43 U.S. Code § 390h–7 - Tucson area water reclamation study
(a) General authority
The Secretary, in cooperation with the State of Arizona and appropriate local and regional entities, shall conduct a feasibility study of comprehensive water reclamation and reuse system for Southern Arizona. For the purpose of this section, the term “Southern Arizona” means those portions of the counties of Pima, Santa Cruz, and Pinal within the Tucson Active Management Hydrologic Area as defined by the Arizona Department of Water Resources.
(b) Federal share
The Federal share of the costs of the study authorized by this section shall not exceed 50 per centum of the total.
The Secretary shall submit the report authorized by this section to the Committee on Energy and Natural Resources of the Senate and the Committee on Natural Resources of the House of Representatives not later than four years after appropriation of funds authorized by sections 390h to 390h–39 of this title.