If you look on the scale of that graph, the amount moved by railroads and trucks is much smaller than moved by pipelines and ships/boats. Railroads and trucks combined are still less than barges.
Canada actually moves an even higher percentage of petroleum by pipeline than the United States (97%). Some of that might be due to Canada's pipeline infrastructure running mostly North to South in order to deliver crude petroleum to refineries in the United States (Canada has a shortage of refinery capacity and is a net importer of refined petroleum).
Looks like the US would need five times as many oil trains to increase the flow by 10% with trains alone.