Despite network congestion and macro-economic headwinds, intermodal achieved solid growth in 2015, according to the Intermodal Association of North America's fourth quarter and year-end Intermodal Market Trends and Statistics report. Domestic container gains more than offset declines in trailer volumes and marginal international increases to achieve overall 2.8 percent growth in total intermodal volumes.

David Latimer, wearing a South Carolina Highway Patrol button on his lapel, was working Capitol Hill one recent morning, warning of the dangers of longer and heavier trucks on the nation's highways.