Agricultural value of additional surface water in the Salt River Valley of Arizona

Abstract

Water for irrigation is a scarce resource in central Arizona. Additional water imported into the Salt River Valley would be of value to agriculture in that it would replace more expensive water that is now being pumped. It would also extend the life of irrigated agriculture in the Valley by slowing the rate of decline in the groundwater table. The major field crop organization of central Arizona was determined, and based on these findings, budgets for field crops were developed. These budgets were organized into typical farm operating units of relevant sizes. Water use within these operating units was then developed and from this use a value for additional irrigation water was determined. The findings indicate that additional surface water is of value to agriculture in two ways. First, it will have an immediate value due to its lower cost, thereby providing for more total net revenue. Secondly, it will be of value in that it will decrease the use of groundwater, thereby slowing the rate of decline in the groundwater table and extending the time when groundwater will be uneconomic to use in agriculture.