IANA said every region it measures "reflected an increase in domestic containers which were responsible for the majority of total third-quarter intermodal gains. Volumes were most impressive in the Midwest and the Northeast regions, with each recording nearly a 15% uptick."

Overall, IANA said, intermodal volume increased a respectable 3.2% during a quarter that exhibited some economic slowdowns. Trailer volume dropped 10.7%, as shippers continued to move away from 45-foot and 48-foot equipment, although 53-foot trailer shipments held close to last year's volumes, dropping only a minimal 0.2% year-over-year, IANA said.

International intermodal volume also rose during the quarter, though more modestly at 0.9%, "with the Northwest and Western Canada regions recording impressive growth during Q3 of 13.8% and 9.1%, respectively," IANA said.