Columbia River. Navigation and flood control on Columbia River and its tributaries, hearings before subcommittee, 74th Congress, 2d session, on S. 869, to improve navigability of Columbia River and its tributaries, to provide for flood control of Columbia River and its tributaries, to provide for reforestation and use of marginal lands in Columbia River basin, to provide for agricultural and industrial development of Columbia River basin, to provide for irrigation of lands in Columbia River basin, to provide for development of electrical power in Columbia River basin, and for other purposes, S. 3330, to authorize completion, maintenance, and operation of certain facilities for navigation on Columbia River, and for other purposes, S. 4178, to authorize completion, maintenance, and operation of certain facilities for navigation on Columbia River, and for other purposes, and S. 4566, to authorize completion, maintenance, and operation of certain facilities for navigation on Columbia River, and for other purposes, May 7-13, 1936.