AZ HB2595

Amends Arizona Revised Statutes Section 45-108 to establish new standards for determining "adequate water supply" for subdivisions outside active management areas.

Requires water to be both "legally available" (usable for at least 100 years under law) and "physically available" (sufficient supply with no detrimental impact on existing uses for at least 100 years).

Specifies that unquantified federal reserved water rights are deemed unavailable for subsequent uses and that private water company certificates of convenience and necessity do not independently demonstrate legal water availability.

Applies new standards only to adequate water supply designation requests not finally issued before January 1, 2019, and only in counties or cities/towns that have adopted specified provisions regarding water supply evaluation.

Maintains existing provisions allowing developers to avoid detailed water supply plans if they obtain commitments from cities, towns, or private water companies already designated as having adequate water supply.