Projections of Water Availability in the Lower Rio Grande, Gila, San Francisco and Mimbres Drainage Basins to 2005

The management of New Mexico water resources requires an understanding of the magnitude and source of future water scarcity conditions. Without detailed information regarding the specific nature of future water scarcity conditions, resource management activities may incorrectly assign priorities to particular scarcity-mitigating efforts. Current and projected water supply and demand conditions are analyzed for the Lower Rio Grande Surface Drainage Basin, the Gila River and San Francisco River Surface Drainage Basin and the Mimbres Closed Basin. This analysis relies on 1980 data and projects future water scarcity conditions over a 25-year period to 2005.

Water use data for 1980 provided by the State Engineer Office is combined with economic and demographic data (from several sources) to allow calculation of water use coefficients for differing water use sectors within the hydrologically defined portions of each county. Future water scarcity conditions are assessed at both the county and basin-wide level in relation to existing water supplies identified by the State Engineer Office.

The analysis identified increased water scarcity conditions in the projection for both the Lower Rio Grande Surface Drainage Basin and the Mimbres Closed Basin. The 25-year projection of water resource demands in the Gila-San Francisco Surface Drainage Basin shows a decline in scarcity conditions.