Submitted to: New Mexico Journal of Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/27/2006
Publication Date: 8/1/2006
Citation: Rango, A. 2006. Snow: The real water supply for the Rio Grande basin. New Mexico Journal of Science. 44:99-118. Interpretive Summary: Few people live near the source of the majority of streamflow in the Rio Grande Basin; namely, the high mountain snow basins, but rather the population is concentrated in large cities in the Chihuahuan Desert. In order to impress upon the public the importance of snow, the potential effects of climate change, and the need to improve water management, various pertinent facts need to be established and documented. The discontinuity between desert and snow source areas are established, the important snowmelt basins are delineated, and a model is usded to forecast flows and evaluate the effects of climate change in 2050 and 2100. Large changes in our ability to manage our valuable water resoruce will be needed if we are to have enough water in 50 - 100 years. With the data in mind, we can move forward a new system to cope with the expected changes. Planners need to take these changes under advisement now in order to have a new system in place in 50 -100 years.
Technical Abstract: The Rio Grande basin in Colorado, New Mexico, Texas, and Mexico is an important drainage in southwestern North America, vital for water consumption by a rapidly growing population, irrigated agriculture, economic development, preservation of endangered species, and energy generation. The most important source of water in the Rio Grande drainage results from snowmelt in the mountains of the upper basin. The gap between water supply and water demand is continually increasing as the population increases, and long term climate change further will affect the amount and timing of streamflow. The criticality of these problems will continue unabated through the 21st Century. Planning to cope with these water management problems needs to move now from relying on projections derived from current storage in reservoirs to additionally incorporating new technologies for measurements and hydrological modeling to allow the development of likely scenarios in both the short and long term. Models that can accept and integrate all types of measurements need to be utilized. Such models exist and are ready to be used operationally. Examples are given of both daily flow forecasts for an entire snowmelt season in the basin as well as predictions of future changes in streamflow to be expected under conditions of climate change. These types of data are vital in deciding among various future options which include the determination of the cost of water, controls on industrial and domestic development, new water distribution and storage systems, and the implementation of water conservation measures.