The U. S. Bureau of Reclamation and the California Department of Water Resources jointly plan to construct a master drain in the San Joaquin Valley for the purpose of collecting and transporting highly saline agricultural drainage waters to a disposal point in the Sacramento - San Joaquin Delta near the City of Antioch. While there is general agreement that such a drainage project will be required to permit the important agricultural economy of the San Joaquin Valley to continue to prosper, there is less agreement as to the resulting effects on the quality of Delta and San Francisco Bay waters of this plan for disposal. The investigation was limited in duration and was completed in December 1966. The report summarizes the findings of that investigation.