Archives West Finding Aid

The Central and Eastern Oregon Township Plats consist of reproductions of the original manuscript plat maps for townships in regions of Oregon east of the Cascade Mountains prepared by the U.S. General Land Office and the U.S. Surveyor General; most of the maps were prepared in the 1870-1890s. Each township of 36 square miles is on a separate sheet. Most sheets have a scale of about 1:31,680 or 2 inches = 1 mile; the remainder are at a smaller scale of about 1.5 inches = 1 mile. These plats cover from Townships 4N to 41S and Ranges 6E to 37 E. Regions depicted in this collection include the Umatilla River basin, Blue Mountains, John Day River basin and tributaries, Snake River, Deschutes River, and Klamath Basin. Boundaries of the Umatilla, Malheur, and Klamath Indian Reservations are shown on the plats. Plats for the Vale and Owyhee Irrigation Projects prepared in the 1930s are included. Several of the plats show mining ditches and placer mining claims in the John Day River basin. The Klamath River, Klamath Lakes and associated marshes, Tule Marsh, and Modoc Lake as well as Fort Klamath and the Klamath Irrigation Project are depicted.

The plats show section lines as well as natural features and vegetation such as prairie; timber, soil types; rivers, streams, sloughs, and wetlands; and fields. The maps include some topographic features. Most of the plats include a narrative description indicating if the township is appropriate for grazing or cultivation, the soil quality, availability of water, and type of timber. Wagon trails and military roads are shown on the plats as well as land claims. This collection consists primarily of single copies of each township plat; however, there are some townships represented by multiple copies of the same plat or different editions of the same township.

Survey Plats as well as Field Note Records for these townships are available online through the Land Status and Cadastral Survey Records website prepared by the Bureau of Land Management - Oregon State Office.