The Taos Plateau in northern Taos County is a high-elevation, basalt-capped plain that lies between the Rio Grande and the Tusas Mountains. The plateau overlaps the New Mexico-Colorado border and forms the west rim of the Rio Grande gorge. The hydrogeologic field investigation of the northern Taos Plateau, conducted between October 2007 and October 2009, is the first comprehensive assessment of groundwater conditions on the Taos Plateau and interactions between local aquifers and the Rio Grande. The investigative approach integrates new and existing geologic, geophysical, hydrologic, and geochemical data. This study has been undertaken in parallel with a major investigation of the springs in the Rio Grande gorge (Bauer et al., 2007). These studies advance understanding of the groundwater system in the northern Taos Plateau, and the interconnection of groundwater and surface water along the Rio Grande in northern Taos County.

In 2005, the New Mexico Bureau of Geology and Mineral Resources initiated a hydrogeology study in the southern Sacramento Mountains with funding from legislative appropriations through the Otero Soil and Water Conservation district. The project was initiated and research funding was continued because of concerns about future water resources for local communities in the southern Sacramento Mountains. Over the past decade, water managers and residents have observed decreasing spring discharge and streamflow in the area, and significant declines of water-levels in wells. Land and resource managers have expressed interest in the potential to increase water availability by thinning woodlands in the mountain watersheds. The focus of this investigation has been to characterize the hydrogeologic framework of the southern Sacramento Mountains and surrounding areas. The results of this study also provide a foundation to assess the impact of tree thinning on groundwater-levels, spring discharge and streamflow in an ongoing study of a small mountain watershed.

In New Mexico, under the pressures of climate change and population growth, demand for water is increasing, and there is mounting evidence that the available water supply may actually be decreasing. While water use conservation efforts are necessary, there is great interest in finding ways to increase the available water supply. Tree thinning in mountain regions is an effective way to decrease fire danger in areas where forests are overgrown. Potentially, tree thinning can also be used as a tool to increase water supply. This report describes a watershed study in the southern Sacramento Mountains, which focused on the effects of tree thinning on the hydrologic system, specifically on the potential to increase groundwater and surface water availability in the Sacramento Mountains.