Ariz. Rev. Stat. § 45-465 – Irrigation grandfathered right; determination of acres entitled to and amount; appurtenancy

A. In an active management area, a person who owns land which was legally irrigated in whole or in part with groundwater at any time during the five years preceding January 1, 1980 for initial active management areas or the date of the notice of the initiation of designation procedures or the call for the election for subsequent active management areas, which is capable of being irrigated and which has not been retired from irrigation for a non-irrigation use pursuant to section 45-463 or 45-469 has the right to use groundwater for the irrigation of such land as determined pursuant to subsections B and C of this section.
B. Except as provided in subsection C of this section, the director shall compute the maximum amount of groundwater which may be used pursuant to this section as follows:
1. 1. Determine the farm units, as defined in section 45-402, within the active management area.
2. 2. Determine the irrigation water duty, as defined in section 45-402, for each farm unit in an active management area, pursuant to sections 45-564 through 45-568.
3. 3. Determine the water duty acres for each farm within the farm unit. The water duty acres are the highest number of acres in the farm, taking land rotation into account, which were legally irrigated during any one year in the five years preceding January 1, 1980 for initial active management areas or the date of the notice of the initiation of designation procedures or the call for the election for subsequent active management areas.
4. 4. Determine the irrigation acres for each farm within the farm unit. The irrigation acres are the acres in the farm which were legally irrigated at any time during the five years preceding January 1, 1980 for initial active management areas or the date of the notice of the initiation of designation procedures or the call for the election for subsequent active management areas, which are capable of being irrigated and which have not been retired from irrigation for a non-irrigation use pursuant to section 45-463 or 45-469.
5. 5. Multiply the water duty acres for each farm within the farm unit by the irrigation water duty for the farm unit and divide that amount by the number of irrigation acres in the farm. The result shall be the maximum amount of groundwater which may be used per year for the irrigation of each irrigation acre in the farm. If the farm is located in an active management area other than the Santa Cruz active management area and is irrigated solely with groundwater, the amount of groundwater used by the farm for irrigation shall be accounted for pursuant to section 45-467, subsection C. If a farm is located in an active management area other than the Santa Cruz active management area and is irrigated with a combination of surface water and groundwater, the amount of groundwater used by the farm for irrigation shall be accounted for pursuant to section 45-467, subsection D. If a farm is located in the Santa Cruz active management area, the amount of water, other than stored water, withdrawn from a well and used by the farm for irrigation purposes shall be accounted for pursuant to section 45-467, subsection E or F.
C. A person who owns land described in subsection A of this section and whose water use on the land is regulated under a best management practices program that is adopted by the director pursuant to section 45-566.02, subsection F, section 45-567.02, subsection G or section 45-568.02, subsection G:
1. 1. Has the right to use groundwater for an irrigation use on the irrigation acres within that land as those acres are determined pursuant to subsection B, paragraph 4 of this section.
2. 2. Is exempt from the provisions of subsection B of this section with respect to that land.
D. The right to use groundwater pursuant to this section for the irrigation of an irrigation acre is an irrigation grandfathered right and is appurtenant to that acre. An irrigation grandfathered right is owned by the owner of the land to which it is appurtenant and may be leased for an irrigation use with the land to which it is appurtenant.
E. A person who owns or leases irrigation acres may use the total amount of groundwater allowed by the irrigation grandfathered right for such acres for the irrigation of all or a portion of such acres.
F. If the irrigation water duty for the farm unit in which an irrigation acre is located is reduced by the director pursuant to article 9 of this chapter, the amount of groundwater which may be used for the irrigation of such acre pursuant to the irrigation grandfathered right under subsection B of this section is reduced accordingly.
G. For purposes of this chapter, the amount of groundwater which may be used or is used is the amount of groundwater withdrawn by the groundwater user, measured at the point of withdrawal, and the amount of groundwater received by the groundwater user from an irrigation district or other source.