Two primary issues have increased focus on water in the Pinal Active Management Area (AMA): 1) the reduced availability of Central Arizona Project (CAP) water, particularly for agricultural users, and 2) difficulties faced by new proposed residential subdivisions in satisfying the physical availability criterion of Arizona’s Assured Water Supply (AWS) Rules. This report consists of over 40 customized graphics to provide background information and a snapshot of the water supply and demand situation in the Pinal AMA in order to build common understanding of current issues in the context of sometimes complicated water topics.

The topics covered in the report were decided based on the conversations with dozens of stakeholders and decision-makers in fall of 2019. The report was then reviewed by Arizona Department of Water Resources and stakeholder experts before release in June 2020. The report was presented in two parts to the Pinal AMA Water Supply and Demand Stakeholder Group, led by Pinal County Supervisor Stephen Miller.

The Pinal AMA’s groundwater budget consists of 1) water that recharges the aquifer and 2) pumping demands that remove groundwater from the aquifer. While intentional and natural recharge can impact groundwater levels over time, groundwater is regarded primarily as a non-renewable supply. The Pinal AMA’s water use remains mostly agricultural, accounting for about 90 percent of the AMA’s total annual demand of 1,113,538 acre-feet (AF) per year.

Especially before CAP water became available, more groundwater had been withdrawn than recharged in Pinal AMA, drawing down available supplies. This overpumping resulted in deeper pumping depths, land subsidence, and earth fissures. Artificial recharge with renewable water or non-groundwater sources has helped rebalance the AMA’s groundwater budget. However, the sheer scale of future groundwater demand will be difficult to offset.

Pinal AMA communities face unprecedented challenges to their landscapes and economies. ADWR’s 2019 Assured Water Supply modeling revealed unmet water demands of 8.1 million acre-feet over 100 years. While it is not the case that there is insufficient water in the Pinal AMA, the unmet demand poses a number of challenges and considerations (e.g. moving resources to areas of need, growth limitations in areas of shallow groundwater, etc.). Local leaders and stakeholders are working on strategies to meet the Pinal AMA's future water needs and their plans will impact generations to come.

Balancing the groundwater budget of the Pinal AMA raises many questions, and numerous uncertainties have the power to impact the future of the area. Agricultural trends, industrial growth, and urban development are major and foreseeable “drivers of change” in the region. Other factors that may potentially affect water supply, demand, and reliability include climate variability, socio-economic changes, water storage decisions, policy, infrastructure, and public behavior and awareness.