AZ SB1176

Creates a new framework for stormwater storage and replenishment credits in the Phoenix Active Management Area, allowing storers to recharge stormwater in constructed underground storage facilities and receive replenishment credits equal to 95% of the recharged volume

Allows replenishment credits to offset groundwater withdrawal obligations within the same subbasin when the withdrawal occurs within two miles of the storage facility or within a water provider's service area that partially overlaps that two-mile radius

Permits transfer of replenishment credits to other eligible entities and directs the Arizona Department of Water Resources to maintain credit accounts, tracking earned, transferred, and used credits

Defines stormwater as rainfall runoff collected from streets, sidewalks, gutters, and other impervious surfaces, explicitly excluding surface water, effluent, incidental recharge, and net natural recharge

Amends water storage permit requirements to recognize stormwater intended for aquifer replenishment as an authorized source, allowing permits to be issued for facilities storing stormwater alone or in combination with other water sources