[Correspondence and reference materials], 1982-1999, undated

The CSU Department of Earth Resources faculty and researchers maintained centralized reference and research files. This collection is comprised of selections of their water-related files with documents dated 1966 to 2004. The largest set of files is research related to water quality, erosion, and sedimentation in the U.S. Virgin Islands, including rain gauge charts, reports, correspondence, and reference materials. Lee MacDonald led much of this work.

Other projects relate to vegetation and forests in relation to fire, acid rain, and oil shale. Aerial photos of the Comanche Alpine Area (now the Comanche Peak Wilderness Area) and Roosevelt National Forest in north-central Colorado exist here as well, along with photos from a flight over the San Juan Basin. Additional materials document a variety of topics or places to a limited extent, including the Upper South Platte River Watershed, Clear Creek, and the 1976 Big Thompson flood.