8001 - Laserfiche WebLink

Home Browse Search

INSTREAM FLOW,- THE NEW MEXICO EXPERIENCE Eluid L. Martinez State Engineer, State of New Mexico Bataan Memorial Bldg., Room 101 P.O. Box 25102 Santa Fe, NM 87504-5102 (505) 827-6160 ABSTRACT New Mexico's surface waters f low into drainages of the Canadian River, the Colorado River and the Rio Grande. The surface-water supply of the state is fully appropriated. New Mexico is a party to eight interstate-stream compacts and subject to two Supreme Court decrees which apportion its surface waters. One-third of the state is under United States government ownership and New Mexico is home to 19 Indian pueblos and three Indian tribes (10 percent of land area). New Mexico's average annual precipitation is about 13 inches, ranging from eight inches in the desert to 30 inches in the mountains. Only a small portion (3 million acre feet) of the average annual precipitation (85 million acre feet) becomes stream flow. New Mexico's average annual surface-water use approximates 1.8 million acre feet of which approximately 62 percent is depleted. Irrigated agriculture accounts for an approximate 79 percent of the state's surface-water use. Surface waters are appropriated for agricultural purposes through the diversion works of eight irrigation districts, seven conservancy districts, and approximately 1,000 acequias and community ditch associations statewide. New Mexico has 24 major water- impoundment reservoirs of 5,000 acre feet or more, with a maximum impound water-storage capacity of 8,449,858 acre feet, of which 2,695,183 acre feet are reserved for flood-control pools. New Mexico is a prior appropriation water-rights doctrine state and all natural waters flowing in streams and watercourses, whether such be perennial or torrential, within the limits of the state, belong to the public and are subject to appropriation for beneficial use. New Mexico, unlike its sister Western states, does not recognize an instream- f low water use. The paper to be presented at the conference will address in part the history of the New Mexico Legislature's attempts to address such a water right. I hear it said that, of the 12 western-most continental states, New Mexico is the only one without a legislative or administrative policy on instream flow. I don't know whether the point is made to suggest that the other 11 states have established, meaningful, and successful instream-flow policies in practice or whether it suggests that New Mexico has yet to enter the environmentally conscious society of the Twentieth Century, or both. In any case, I want to talk briefly this morning about the status of instream flow in New Mexico. Let me first generally acquaint you with the state I represent. New Mexico is approximately 400 miles long and 350 miles wide. It has almost 122,000 square miles of surface area. The Southern Rockies extend into New Mexico. On the average, rainfall varies from 35 inches a year in the northern mountains to eight inches a year in the lower plains, for a state average of 14 inches a year. New Mexico's bright sun and a dry atmosphere cause evaporation rates to vary from 30 inches a year in the northern mountain to 80 inches a year at the more and plains. The state is semi-arid. Two major rivers, major at least by our standards, dissect the state from north to south. The Pecos (which originates in northern New Mexico) meanders some 500 miles before leaving the state and, by compact, its flow is shared with Texas. The Rio Grande (which originates in the mountains of southwest Colorado) also meanders some 500 miles within the state and, by compact, the flow is shared with Colorado and Texas. By international agreement, the Rio Grande's flow is shared with Mexico. Of the 4,228,000 acre feet of water withdrawn in the state in 1990, 1,975,000 acre feet, some 47 percent of the total, came from ground sources, reflecting a dependence on groundwater that is virtually as great as the reliance on surface waters. Notwithstanding its expanse, limited water supply, and significant evaporation rate, New Mexico is not without instream or perennial flows in portions of certain river and stream systems. Some of that flow exists naturally, nurtured and protected by the terrain itself. Some of it is developed, the product of dams and reservoirs. New Mexico does not have a formalized instream-flow policy, but it is neither a new issue nor a dead issue in the state. In the early `70s, concern with rivers and streams produced legislative bills aimed at developing state- sponsored wild and scenic rivers.' In 1990, the state legislature considered two more bills dealing with the natural and scenic beauty of New Mexico rivers, and a third bill by which the definition of "beneficial use" would have been expanded to include instream, non-diversionary uses of water for the maintenance, enhancement, and protection of wildlife.' In 1984, an amendment was introduced which made the diversion of water from its natural channel unnecessary for beneficial use, provided the water left in the channel was used for the propagation or maintenance of fish and 40