West Coast slowdown: major congestion at Southern California ports collides with international strike threat.(Rail & Intermodal)

Container ships began stacking up in Southern California ports last week in what port officials said could turn into a "major congestion event" caused by labor shortages. The work slowdown coincides with a week-long strike threatened by independent intermodal truckers through the July 4 holiday at U.S. ports and could further slow down freight already caught up in congestion on the highways and the rail lines.

"We currently have 11 ships anchored with three more scheduled to go to anchor upon their arrivals later today," said Capt. M.H.K. Aschemeyer, Executive Director of the Marine Exchange of Southern California, in a memo to members on June 28.

"Tomorrow, …