At issue is where authorities will find enough water to replenish aquifers in fast-growing areas of Pima, Pinal and Maricopa counties where groundwater is or will be pumped to supply new homes, because they don’t have access to CAP water.

The report focuses on the work of the Central Arizona Groundwater Replenishment District, a part of the CAP, whose job is to find the renewable supplies for those homes in the three counties. Under state law, the homes in these areas can be built only if renewable supplies can be found to compensate for the water pumped to serve them.

In the Tucson area, such development is occurring or is projected to occur over the next few decades in unincorporated areas north, south, northwest and southeast of the city. The areas include the Green Valley and Quail Creek areas south of Tucson, the SaddleBrooke area just north of the Pinal County border, and the Vail area southeast of Tucson.

Far more intense future development and pressure on water supplies is expected for Pinal County closer to Phoenix and for the Buckeye area west of Phoenix.