In 1904, the California-based Richardson Brothers Company and its subsidiary, Richardson Construction Company, established Compañia Constructora Richardson to handle its interests in Sonora, Mexico. W.E. Richardson, Davis Richardson, and H.A. Sibbet were the executives. The purpose of the company was to build a railroad line and develop an irrigation system in the Yaqui River Valley, for agricultural and real estate development. The rights to build railroads on company land was sold to the Southern Pacific Railroad Company. The Compañia was acquired by the Mexican government in 1927, and became Irrigadora del Yaqui, S.A.
Photographs comprise the major part of the collection; legal papers and descriptive material are also included. The photos document the company projects from the excavation stages to completed dams. Also depicted are the port city of Guaymas and other Sonoran locations, Yaqui Indians, petroglyphs, the Richardson family and home, mines, and other subjects of local interest; some concern the Mexican Revolution. A report "Background material on irrigation development of the Yaqui Valley, Sonora, Mexico, and the sale of the project to the Mexican government" was written by company attorney Chandler P. Ward in 1968. Original and copied legal papers include tax receipts, information on land sales, stock transfers, and deeds. Printed information includes publicity pamphlets produced by Compañia Constructora Richardson; a stockholder report with map; a booklet "The Land Laws of Mexico;" and several contracts with the Mexican government. Some materials are in Spanish.