The backlog of cargo ships sitting off the coast will soon have a more orderly queue further off the coast under a plan from maritime industry leaders designed to reduce air pollution and congestion.

The ports of Long Beach and Los Angeles, which together handle 40% of the nation’s imports, have been grappling with a massive supply chain crisis this year as dozens of container ships sit backed up just offshore. On Tuesday, a record 111 container ships were at anchor or adrift off the coast, according to the Marine Exchange of Southern California.

The backlog has prompted concerns about air pollution spikes, especially in nearby neighborhoods, like Long Beach’s Westside, that have long seen higher asthma and cancer rates.

Under the new queuing process effective Nov. 16, ships will be assigned a spot in the arrival queue based on the departure time from their last port of call. They will be required to anchor 150 miles offshore, rather than hugging the coast, as they wait for an available berth.

The plan from the Pacific Maritime Association, Pacific Merchant Shipping Association and Marine Exchange of Southern California, will require ships to slow their speed and spread out, which will reduce the number of ships at anchor before the onset of winter weather, as well as reduce air emissions near the coastline, according to a news statement.

Under the current system, container ships enter the arrival queue based on when they cross a line 20 nautical miles from the San Pedro Bay Port Complex.

“The San Pedro Bay Ports play a critical role in California’s statewide economic health,” PMSA President John McLaurin said in a statement. “This system delivers a pragmatic solution through order and predictability that will reduce the number of ships idling off the coast in the coming months, improve safety, and support the efficient movement of container-based goods.”

The new process will not apply to ships currently in the arrival queue and could take several weeks to implement. 

Port of Long Beach Executive Director Mario Cordero said in a statement that the harbor welcomes the new plan.

“Coupled with the measures being implemented by the ports and our other partners–as well as the support of the Biden Administration–we are confident we can catch up with the backlog,” he said. “It’s important that we get the supply chain flowing smoothly again, as soon as possible.”