The Mary Armstrong Milligan papers (1882-2009) contain journal excerpts, correspondence, a handbook, and scrapbooks dealing with Milligan's involvement in river rafting in the Western United States. Milligan was a participant in the South Cottonwood Ward organization (SOCOTWA), a semi-private river outfitter that began after World War II.

The Norman D. and Doris Nevills papers (1890s-1952) constitute one of the finest and most comprehensive collections of original research materials on the history of travel on the Colorado and Green Rivers and their tributaries. Included are correspondence, diaries, logs, subject files, news clippings, and business records. Norman Nevills (1909-1949), supported by his wife Doris, was one of the pioneers of commercial river running.