AZ SB1660

Amends Arizona water law to define and regulate effluent from industrial facilities that treat water on-site to meet aquifer water quality standards, allowing such effluent to be stored in underground storage facilities.

Requires effluent stored at constructed underground storage facilities to remain at the site where the water was used, and permits new water storage applications for this effluent only if filed by December 31, 2025.

Establishes that long-term storage credits earned from storing industrial effluent may only be used at the same site where the water was stored, with the director crediting 75 percent of the recoverable amount to the storer's long-term storage account.

Requires the director to submit an annual report by June 30 to the governor and legislature detailing the number of effluent water storage permits issued, total water stored, and total water withdrawn in the preceding calendar year.

Amends the aquifer protection permit exemptions to exclude facilities that treat and store effluent as defined in the revised statute from exemption status.