Since the spring of 1999, NMWA has conducted an ongoing field inventory of public wildlands throughout the state of New Mexico. The purpose of this inventory is to assess the suitability of public lands for Wilderness designation, and to identify any illegal activities or impacts within designated Wilderness or Wilderness Study Areas (WSAs). A staff of professionals directs and manages the Wilderness Inventory Program. The inventory program is currently comprised of two types of surveys: Roads, Boundaries & Impacts Survey and Wilderness Characteristics & Values Survey.

The Roads, Boundaries and Impacts Survey is conducted by trained field staff, paid contractors, and dedicated volunteers. As the title implies, the purpose of this type of survey is to document the roads and various human impacts that affect and define the boundaries of potential wilderness areas. This includes, but is not limited to, roads, stock developments, pipelines, power lines, mining scars, etc. Before on-the-ground inventory documentation occurs, every potential inventory unit is analyzed with the most current aerial photos and/or other available remote imagery. Apparent impacts not shown on existing maps of the potential unit are transferred to US Geological Survey 7.5 minute maps for on-the-ground documentation. On-the-ground inventory involves photo-documenting every road and human impact within an inventory unit that shows up on existing maps and remote imagery. During this portion of the inventory any routes and other impacts found that did not appear on any of the maps or remote imagery are also documented with great care. For every route a photo is taken that shows the beginning of the route, the end of the route, average conditions, and purpose (if any) for the route. Supplemented by field notes, this process records the condition, level of maintenance and use, and functionality of the human impacts within the area. All fieldwork is reviewed for accuracy and completeness.

The Wilderness Characteristics and Values Survey is led by professional staff and conducted by trained volunteers. This type of survey documents the characteristics and values found in the interior of potential wilderness areas. Those who conduct this type of survey are encouraged to take pictures of characteristics such as the area’s naturalness, flora and fauna, geological formations, and scenic views of and from the area. Values assessed include the opportunity for solitude and various types of unconfined and primitive recreation such as hiking, backpacking, horseback riding, sightseeing, etc. Other features of cultural, archeological, ecological, scientific or educational value are also documented. To complement photo documentation, volunteers are encouraged to take notes about the subject matter of their photos, and to write about their experiences, impressions of the area and its suitability for wilderness designation.