46 U.S.C. § 55603

assess the extent to which States, local governments, and Tribal governments include marine highway transportation and other marine transportation solutions in transportation planning;

encourage State and Tribal departments of transportation to develop strategies, where appropriate, to incorporate marine highway transportation, ferries, and other marine transportation solutions for regional and interstate transport of freight and passengers in transportation planning; and

encourage groups of States, Tribal governments, and multistate transportation entities to determine how marine highways can address congestion, bottlenecks, and other interstate transportation challenges.