SIMIC

Jim Newsome, head of the South Carolina Ports Authority that owns and operates the port, said he now expects the backlog to be cleared by mid-April after earlier estimating that the armada of vessels offshore would dissipate by mid-March.

"There's really not a minute except for when a ship leaves and when a ship comes that the berth is empty," he said. "They're working. But the productivity is not what it could be when a terminal is full like this." That has left some ships staying longer as containers are loaded and unloaded, he said.

The backlog at Charleston, the fourth-busiest gateway for container imports on the east coast, is growing as the lengthy queues have grown at the ports of Los Angeles and Long Beach, but now appear to be easing.

A large backup off Georgia's Port of Savannah reached around 30 vessels in September, but the port says the flow of ships improved after it added space to store more containers on shore.

The number of ships in the queue for the California ports slipped to 72, according to the Marine Exchange of Southern California, down from a peak of 109 on January 9.

The import surge has been fueled by a rush to restock inventories that were depleted early in the pandemic and as retailers have pressed to meet strong consumer demand, triggering shortages of freight handling equipment, truckers and warehouse space.

Last year, the Port of Charleston handled a record 1,294,901 TEU, a 25.4 per cent increase over the year before, making it one of several east coast ports that saw inbound volumes grow more than 20 per cent year on year.

The backup in Charleston started forming around Thanksgiving, as large holiday inventory orders reached the US and container lines and their shipping customers sought to divert cargo from swamped west coast ports to alternative gateways. That has created congestion at some east coast ports.