The International Longshore and Warehouse Union vigorously disputes that figure. Spokesman Craig Merrilees said wages typically range from $26 to $36 an hour and noted that many longshoremen are not full-time employees.
As the two sides quarrel, a backup of ships that extends into the Pacific will only grow. On Thursday, 14 ships laden with containers of goods were anchored outside the ports of Los Angeles and Long Beach; another 11 were awaiting berths outside the ports of Oakland or Seattle and Tacoma in Washington.
Among the importers with goods on the water is AICO Furniture, whose manufacturers are in Asia. In total, 70 containers are either stuck or on their way with no obvious way to get unloaded, said Martin Ploy, the company's president.
"When Mrs. Jones calls the furniture store and says, `I've been waiting for months now. When am I going to get this?' they don't have a good answer," Ploy said. "It challenges everybody's credibility. The consumer gets angry with the retailer, the retailer gets angry with us. And of course, we're angry with this whole situation here."
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At a Capitol Hill news conference, lawmakers discussed other impacts of the backlog. Rep. Bob Gibbs, R-Ohio, said a major supplier of medical equipment in his state told him it is rationing protective clothing for health care workers because of trouble getting imports.
Exporters also are suffering, notably producers of products such as hay and potatoes, as well as pork and beef.
"There's nothing we produce in agriculture or forest products that can't be sourced somewhere else in the world," said Peter Friedmann, executive director of the Agriculture Transportation Coalition. "You can get it somewhere else in the world, and they are."
Cargo began moving slowly across the troubled West Coast waterfront months ago. Containers that used to take two or three days to hit the highway have been taking a week or more.
Some importers have reacted by diverting shipments to ports on the East and Gulf coasts. Others have turned to air cargo, paying a premium that can be five or more times more than the cost of sea-borne shipments.
In recent days, the union said companies are exaggerating the extent of congestion so they can cut dockworker shifts and pressure negotiators into a contract agreement.
Negotiations resumed Thursday in San Francisco—the first day the two sides have met since Feb. 6—amid increasing pressure from elected officials and businesses to reach a deal.