Canada’s largest freight railroad is ending service to Maine’s truck-and-rail hub in Auburn, citing insufficient freight volume for a move that jeopardizes the future of the only such transportation center in the state.

The 35-acre terminal, which opened 20 years ago, connects Maine shippers with the Canadian National Railway and its straight run across the continent to the port of Vancouver and a new container terminal in Prince Rupert in British Columbia.

The Auburn terminal has large-lift vehicles called “reach stackers” that pick up containers off truck chassis and place them on flatbed rail cars. This allows companies that don’t have direct rail access to ship freight on trains. L.L.Bean in Freeport, which uses the Auburn facility to receive a “significant” amount of its freight from Asia, could be affected by the change, according to L.L.Bean spokeswoman Carolyn Beem. She said the company is monitoring the situation and has a plan in place for moving goods if it’s unable to use the hub.

“CN is terminating its rail service to the Auburn Intermodal Terminal because traffic volumes are not sufficient to sustain that service,” said Jim Feeny, director of public and government affairs for the railway.

Though the center will remain open, the short-line railroad that operates it, the St. Lawrence & Atlantic Railway, is only 157 miles long, beginning at Portland’s East Deering neighborhood and ending in the suburbs of Montreal.

There is no truck-and-rail hub at the end of the line, said Chalmers Hardenbergh, publisher of Atlantic Northeast Rails and Ports, an industry newsletter.

“Nobody is going to use it because there is nowhere to go,” he said.

Officials at St. Lawrence & Atlantic did not return phone calls.

Canadian National on Friday sent a notice to shippers that its service to the Auburn facility is being discontinued effective Nov. 15. It said that Nov. 1 will be the last day it will pick up Auburn-bound containers from ports in Vancouver and Prince Rupert, and Nov. 5 will be the last day for picking up containers in the Port of Halifax.

The railroad will still be hauling tanker cars and box cars to Auburn. Savage Safe Handling, which has direct rail access to the St. Lawrence & Atlantic Railway at its Auburn plant, won’t be affected by the change because it doesn’t use the Auburn terminal, company officials said.

Hardenbergh said volumes at the Auburn terminal have been declining for more than a decade. At its peak in 1998, about 12,000 containers moved through the terminal, he said, but by 2009 the terminal moved only 800 containers. He said Genesee & Wyoming Inc., which bought the line in 2002 from Emons Transportation, has stopped reporting data.

The new owner has never reported annual numbers. Hardenbergh believes that volumes have continued to decline because of competition from truck-and-rail hubs in Massachusettts, in Ayer and Worcester. The competition intensified in 2009 when Pan Am Railways and the Norfolk Southern Railway joined forces to improve the rail route between eastern Massachusetts and Albany, New York.

While the Auburn facility lost its domestic shipping business to Massachusetts, it continued to serve shippers importing or exporting cargo overseas, Hardenbergh said.

In 2003, the U.S. Customs Service designated the Auburn facility as an official port of entry into the country, allowing customs agents to inspect containers there. The industrial park adjacent to the facility is designated as a Foreign Trade Zone, allowing companies to defer or avoid paying duties and tariffs on imported goods.

Hardenbergh said the loss of the terminal would make it harder for Auburn and Lewiston to market the region to companies looking to relocate or expand.

Auburn and the state and federal governments have invested millions of dollars on infrastructure improvements in the area, Auburn Mayor Jonathan P. LaBonté said, noting that the center still will be able to offer access to global markets via the port of Portland.

However, Portland is focused on building its own container service with Europe and the North Atlantic, as well as developing shipping service along the Eastern Seaboard, said Patrick Arnold, who manages Portland’s International Marine Terminal.

“They can work with Portland, but it’s a different product,” he said. “We are not offering (overland) service to the West Coast of the U.S. and Canada.”