This series consists primarily of general correspondence and minutes from CBIAC meetings. The correspondence deals with a variety of subjects related to projects, subcommittee operations, specific water management problems and routine administrative matters. Minutes from the Pacific Northwest Governor's Powers Policy Committee (1954), the Water Resources Committee (1959), and the Centennial Meeting (1959) are also included.

Reports associated with programs, planning, budgets and resources are intermixed with the correspondence. Stream flow data is included in the 1950, 1955 and 1959 files. Meeting notices, agendas, copies of legislation, newsletters and newspaper clippings are also interfiled.