Ranegras Plain Becomes Arizona’s 8th AMA
The Arizona Department of Water Resources (ADWR) has designated the Ranegras Plain Groundwater Basin Arizona’s eighth Active Management Area (AMA). This designation follows the determination by ADWR Director Tom Buschatzke that the basin is experiencing severe groundwater declines.
Water users in the Ranegras Plain, which is located in southwest Arizona, primarily in La Paz County, rely entirely on groundwater for agricultural, industrial, commercial, and residential needs. Pumping in the basin has increased dramatically over the past decade, and groundwater levels have fallen by more than 200 feet since the 1980s. These declines have led to significant land subsidence, which threatens long-term groundwater storage.
The AMA designation was made after a multiyear process beginning in August 2023, which included hydrological analysis and extensive community involvement through public meetings, a public comment period, and a formal hearing in December 2025. ADWR received more than 400 public comments regarding this decision, with the majority supporting AMA designation.
As an AMA, the Ranegras Plain Groundwater Basin will be subject to groundwater measurement and reporting, formalized groundwater rights, and locally informed management plans that specify conservation measures. ADWR officials say these steps are critical to protecting the basin’s finite groundwater resources and ensuring a sustainable future for residents and businesses.