The Water Resources Collection was developed in the 1930s by then Librarian Willis Holmes Kerr, Librarian, and Claremont Colleges Trustee John Treanor. At this time, the water problem interested both men, and they began to collect materials on the subject of water, its distribution, augmentation, and use in Southern California. By traveling to the Hoover Dam, the Imperial Valley, into Arizona, and to the San Joaquin Valley, they assembled literally tons of records: reports of engineers, annual reports and minute books of boards of directors of water companies, documents of federal and state governments, promotional pamphlets, newspaper clippings, and a host of other materials.
Though the main focus of the Water Resources Collection of Southern California covers the early years, from the 1900s to the 1950s, Professor Merrill Goodall of the Claremont Graduate University has given recent publications from California state and local agencies. He was a member of the California Water Commission, 1977–1985, and participated in state, regional, and local water projects. Other donors to the Water Collection include the California Water Resources Center, the Metropolitan Water District, and the Three Valleys Water District, which is the main source of water to Claremont. Such a vast collection has defied complete cataloging, but in spite of this, it has been and continues to be used extensively by scholars.