The plan for channel improvements and appurtenant works for flood control on that portion of the Truckee River and tributaries within the State of California, is adopted and authorized substantially in accordance with the recommendations of the Chief of Engineers in House Document No. 497, Eighty-third Congress, Second Session, as authorized by Act of Congress approved September 3, 1954, Public Law 780, Eighty-third Congress, Second Session, at an estimated cost to the State of twenty thousand dollars ($20,000).