Because of the statewide interest in navigation, the state will hold and save the United States of America free and harmless from liability for damages to the parallel tubes between the Cities of Oakland and Alameda included in the description of Route 260 due to the initial dredging work and subsequent maintenance dredging in an area within 50 feet of said tubes in connection with the deepening of the Oakland Estuary by the Corps of Engineers of the United States Army and the Director of Finance shall execute an agreement so to do with the proper representatives of the United States of America.