ECONOMIC-ANALYSIS OF SPRINKLER AND SIPHON TUBE IRRIGATION SYSTEMS, WITH IMPLICATIONS FOR PUBLIC POLICIES

This paper examines the economic rationale for using sprinklers for in itial irrigation events, while using siphon tubes for remaining irriga tions on the same crop, using cost data and descriptive information fr om an irrigation district on the west side of California's San Joaquin Valley. Many farmers in the region began using sprinklers for pre-irr igating cotton fields and for early irrigations on tomatoes, in respon se to reductions in water supply and rising water prices, during 1990 through 1994. However, most farmers continued using siphon tubes for s ummer irrigations on both crops. The fixed and variable costs of using sprinklers and siphon tubes are examined, and the potential improveme nts in crop yield that may be achieved when using sprinklers, to deter mine the economic rationale for these decisions. Results suggest that agencies wishing to encourage improvements. in water management practi ces should implement policies that reduce the initial cost of sprinkle r systems, while permitting farmers to choose the best combination of irrigation methods. (C) 1997 Elsevier Science B.V.