The collection consists of correspondence, reports, documents, and memoranda, relating to California's Central Valley Project, Lake Tahoe, East Bay Municipal Utility District, Pacific Gas and Electric Company, and public water and power supply system for other California municipalities.

The collection consists of correspondence, reports, legislation, and memoranda concerning the diversion of water from the Klamath and Trinity Rivers into the Sacramento Valley, California.

The collection consists of primarily published and unpublished reports, prepared by Conkling in his capacity as a consultant in Los Angeles, California, pertaining to water resources development in Southern California.

The collection consists of press releases, speeches (many by former DWR Directors), news clippings, reports, photographs, and miscellaneous memoranda on California water resources development during the period 1950-1965.

The collection consists of reports, legal opinions, and comments concerning the Central Valley Project, water districts and reclamation districts, and water rights on the San Joaquin River and elsewhere in California.

The collection consists of unpublished reports pertaining to water power and water supply in California, compiled by Lester S. Ready, former chief engineer of the State Railroad Commission and consulting engineer.