Survey sees little threat of peak congestion.

Major container ports in the U.S. are operating smoothly, and importers foresee little risk of the congestion that has jammed gateways in the past, according to the June Port Tracker released by the National Retail Federation.

"The ramp-up into peak season is now under way, with monthly container volume building through October," said Paul Bingham, economist with Global Insight, which co-authored the monthly survey of port conditions. "There is no congestion at the ports now, and the truck and rail systems are operating fluidly."

Bingham said growing volume and port trucking pose a challenge to container transportation later this year, "but the backlog of …