Arizona’s Groundwater Savings Program

One of the more interesting and sometimes debated elements of Arizona’s Groundwater Storage and Recovery Program is the Groundwater Savings Program (GSP). The program was developed when Arizona was struggling to utilize its Central Arizona Project (CAP) water. Agricultural water users rejected the use of CAP water due to its high cost relative to groundwater. Yet, the higher the ratio of agricultural to municipal use, the lower were Arizona’s CAP repayment obligations to the federal government, according to the formula used at the time. By the early 1990s, it was clear that both the municipal and agricultural sectors would benefit from a program designed to increase agricultural use of CAP water.