The unprecedented flood of containerised imports into the Port of Los Angeles in the US is not just causing headaches for importers, according to its executive director.

The ongoing import surge is also hurting exporters because importers are sending empty boxes right back to China to pick up more imports, making none available for US exporters, Gene Seroka said.

"We must get our exporters back in the game," he said on Wednesday during the port's monthly press conference.

"We've made some very solid recommendations to the Biden administration, including creating the right incentives to start turning around these numbers quickly."

Boxed export volumes in August surpassed 100,000 teu for the first time since May of this year, but they are still down 23% from a year ago, he said.

"That's not much to celebrate," he said.

The ratio of imports to exports has improved slightly to 4.8 to 1 since July, but exports since 2018 are down 30 of the last 34 months.

Empty boxes are China-bound

"Conversely, empty containers continue to climb, and you would expect that with the rising imports that we've seen over the past year," Seroka said.

The port sent 367,000 teu in container volume back to China in August, representing a 17% jump in volume sent 12 months ago.

"That's more empties than we've ever processed in one month beating the previous high that was set just back in May by 1,000 teus," he said.

Meanwhile, the port took in slightly more than 954,000 teu in boxed imports in August, pushing the number of anchored ships waiting for a berth in San Pedro Bay to record levels.

The Port of Los Angeles had 32 ships at anchor on Wednesday, while nearby Port of Long Beach had 27 vessels.

"That's because last August retailers were really beginning to ramp up on imports to restock shelves after the initial wave of the pandemic-induced buying surge that began last year," Seroka said.

"The big picture is that imports remain strong."