The Energy Impact on Irrigated Agricultural Production of the Southwestern Closed Basins, New Mexico

A linear programming model was utilized to simulate a 20 year (1978-1998) crop production and irrigation water utilization pattern in the Southwestern Closed Basins of New Mexico under four alternative energy price projections–base. low. medium and high.

Under the simulation, approximately 75,700 acres of land would be farmed in 1978, remaining constant through 1998. Cotton accounted for 47 percent of the irrigated cropland, corn for grain 31 percent, grain sorghum 16 percent, and wheat 6 percent. However, under the high energy price alternative. irrigated crop agriculture ceased in some areas in 1996 and in other areas in 1998.

Net returns to land and risk varied widely among the four energy price projections ranging from an increase of one percent in the base alternative from 1978 to 1998 to a 62 percent reduction in net returns in the high energy price alternative through 1998. The reduction in net returns from 1978 to 1998 for the low energy price alternative was about 23 percent and about 40 percent for the medium energy price alternative. The reduction in net returns was due primarily to the rapid escalation of diesel fuel prices. The diesel fuel cost for the high alternative was expected to increase 269 percent, 185 percent for the medium alternative, and about 119 percent for the low alternative over present costs.

The returns to risk, after imposing a charge for the use of irrigated cropland valued at $800 per acre, was $70 per acre in the base year of 1978. The returns to risk declined under the low ($49) and medium ($23) energy price alternatives in 1998. Under the high price alternative the net return to risk was estimated at a negative $10 per acre in 1998.

The amount of irrigation water pumped in the Southwestern Closed Basins would remain constant over the 20 year period for the energy price alternatives, except 1996 and 1998 under the high alternative when pumpage declined. The total declines in the water tables were estimated to be about 41 feet in the Mimbres-Uvas Basins, from 102 to 126 feet in the Columbus-Hermanas Area, about 34 feet in the Lordsburg-Animas Basins, and from 6 to 7 feet in the Playas Basin. In addition, there were changes in energy sources for pumping irrigation water, irrigation pumping plant efficiencies and energy costs for pumping irrigation water among the alternative energy price projections.

The annual labor requirements and cost as well as the annual operating capital requirements remained constant except under the high alternative when a decline occurred in relation to the decline in acreage.

Project No. WRRI 3109-410, 1423693, 1423694