MONTREAL -- A rail blockade in eastern Ontario has led to backlogs at Canada's three biggest ports, prompting some shippers to take their business elsewhere as cargo piles up and dockworkers' paycheques shrink.

The protest along Canadian National Railway tracks east of Belleville, Ont., has halted CN's eastern network -- about one-quarter of its operations -- and choked shipments from coast to coast.

Atlantic Container Line (ACL), a major U.S. shipping line, is diverting from the Port of Halifax in favour of U.S. harbours. The company, which typically berths two ships a week, is now docking in New York and Baltimore to run cargo inland on U.S. railroads, said chief executive Andrew Abbott.

"It's our gateway port for North America. So if you take out the rail, it knocks out 90 per cent of the cargo that we were putting on the ship," said Abbott, whose company has been calling on the Halifax port for more than 50 years.

ACL typically handles the equivalent of about 2,000 20-foot containers a week in Halifax that carry everything from Ontario auto parts to French cheese.

"It's commercial damage to Canadian manufacturers. It's financial damage to the guys who are bringing in French wine or Walkers butter cookies, because they're not going on the shelves," Abbott said. "Everybody's paying a piece."

Halifax longshoremen are also working -- and earning -- less, as more than 60 per cent of freight that passes through the port is bound for trains that can no longer be loaded, port authority spokesman Lane Farguson said.

The blockade disrupts business for everyone from stevedores to truckers, packers, importers, exporters and the ports and railways themselves, he said of the "cascading effects" of the shipping ecosystem.

"It is certainly a challenging situation for everyone involved."

In Montreal, some 4,000 containers sit immobilized on the docks and Prairie bulk products like grain can no longer reach the port.

"We are obviously concerned about this situation, which has significant impacts on the economy and the transport logistics chain serving the port," spokeswoman Melanie Nadeau said in an email.

Meanwhile, the number of ships waiting at anchor to enter Vancouver-area terminals has more than doubled to 50 due to the clogged transportation system, though no vessels are opting for U.S. ports as a result, said Vancouver Fraser Port Authority spokeswoman Melanie Nadeau.

Nearly two weeks ago, protesters barred road access to Canada's biggest freight hub for several days, one of many pop-up blockades at ports, rail lines and roads across the country.

CN closed its critical eastern network eight days ago after protesters set up a blockade in Tyendinaga Mohawk Territory on Feb. 6 in support of Wet'suwet'en hereditary chiefs who oppose a natural gas pipeline slated to pass through their traditional lands in British Columbia.

This report by The Canadian Press was first published Feb. 21, 2020.