On an earnings call Thursday, Union Pacific officials said it also temporarily reopened a former intermodal facility in the Chicago area to alleviate congestion. Chief Executive Lance Fritz said shippers are struggling to take boxes quickly enough from the railroad’s ramps to warehouses and distribution centers.

This week, BNSF said it had begun metering container flows from the ports for two weeks. Typically the railroad meters freight following disruptions caused by events like extreme weather, said a spokeswoman for BNSF, a unit of Berkshire Hathaway Inc.

“This particular situation is somewhat unprecedented in that for a sustained amount of time the volume we are getting is exceeding what customers are picking up from our gates for deliveries,” she said in a statement.