Irrigation-Dependent Wetlands Versus Instream Flow Enhancement: Economics of Water Transfers from Agriculture to Wildlife Uses

Abstract

Irrigated agriculture throughout western North America faces increasing pressure to transfer water to nonagricultural uses, including instream flows for fish and wildlife management. In an important case, increased instream flows are needed in Nebraska’s Platte River for recovery of threatened and endangered fish and wildlife species. Irrigated agriculture in the Laramie Basin of southeast Wyoming is a potential water source for the effort to enhance instream flow. However, flood irrigation of hayfields in the Laramie Basin has created many wetlands, both ephemeral and permanent, over the last century. Attempting to increase Platte River instream flows by purchasing water rights or improving irrigation efficiency in the Laramie Basin would transform irrigated agriculture, causing a substantial fraction of the Laramie Basin’s wetlands to be lost. A creative solution is needed to prevent the sacrifice of one ecosystem on behalf of another. A rotating short-term water-leasing program is proposed. The program allows Laramie Basin producers to contribute to instream flows while continuing to support local wetlands. Permanent wetland desiccation is prevented and regional environmental water needs are met without impairing local ecological resources. Budget analysis is used to provide an initial cost estimate for acquiring water from agriculture through the short-term leasing program. The proposed approach is more expensive than traditional programs but allows contribution to instream flows without major wetland loss. Short-term leasing is a more efficient approach if benefits from wetlands exceed the difference in cost between the short-term lease program and programs that do not conserve wetlands.

Appendix

Columns (A) and (B) indicate Laramie River water yields between April 1 and October 1 (recorded annually for years 1974 to 2002) (Sprangers 2004). Column (C) indicates hay production for Albany County, Wyoming (production data exclusively for the Laramie Basin was not available) (National Agricultural Statistics Service 2004). Column (D) indicates to which “water availability” category each water year was assigned (agricultural drought, average, or above average). The frequency of category occurrence is used in Table 1

Water year	(A) Total water yield (acre-ft)	(B) Total water yield (million m3)	(C) Hay production (tons)	(D) Category assigned
1974	158,000	194.814	85,900	Average
1975	119,200	146.974	95,840	Average
1976	98,350	121.266	123,010	Average
1977	65,700	81.008	102,400	Average
1978	142,500	175.703	132,600	Above
1979	158,200	195.061	145,550	Above
1980	149,200	183.964	113,000	Average
1981	65,580	80.860	120,900	Average
1982	154,800	190.868	105,500	Average
1983	292,700	360.899	137,800	Above
1984	210,700	259.793	105,000	Average
1985	142,300	175.456	81,800	Average
1986	220,400	271.753	93,200	Average
1987	73,600	90.749	83,900	Drought
1988	120,500	148.577	79,000	Average
1989	60,740	74.892	35,900	Drought
1990	95,450	117.690	62,300	Drought
1991	97,910	120.723	156,000	Above
1992	84,190	103.806	90,000	Drought
1993	135,200	166.702	90,300	Average
1994	80,260	98.961	65,100	Drought
1995	150,000	184.950	79,500	Average
1996	165,300	203.815	76,400	Average
1997	177,000	218.241	112,800	Average
1998	124,000	152.892	118,100	Average
1999	117,020	144.286	155,400	Above
2000	85,149	104.978	131,000	Above
2001	54,530	67.235	90,000	Drought
2002	15,490	19.099	38,800	Drought
Average	124,619	153.656	100,241	—