Erica Phillips at The Wall Street Journal reports that as much as 10% of cargo from Asia could shift from West Coast to East Coast ports, a new study finds.

A new report estimates that up to 10% of cargo moving from Asia to the U.S. could shift from West Coast to East Coast ports after the Panama Canal expansion is completed next year.

The nearly-decade-long modernization of the canal will have “profound effects” on the ways goods move around the world, the report’s authors, with The Boston Consulting Group and logistics company C.H. Robinson Worldwide Inc. said. West Coast ports will lose market share, their report found, while truck and rail investment may need to shift to accommodate new domestic routes.

The new Panama Canal “promises to reorient the landscape of the logistics industry and alter the decision-making calculus of the shippers that the canal serves,” the report said.

So far, expanding the 100-year-old waterway has endured delays and racked up costs well over $5 billion. But the new wider, deeper waterway will make it possible for larger oil tankers and container ships to travel the 50 miles between the Pacific and Atlantic Oceans. Right now, many ships are too big to fit through narrow stretches of the canal, which taper to as little as 110 feet wide in some places.

West Coast ports, which currently handle about two-thirds of cargo containers from East Asia, will see that fraction get smaller, the report said.

“For shipping to many destinations, using West Coast ports will still be the fastest option—but it won’t necessarily be the cheapest,” the report found, because transport inland from the West Coast adds significant extra cost. Cargo volumes will continue to grow in Los Angeles, Long Beach, Oakland and Seattle, though at a slower rate.

East Coast ports will benefit the most, as goods bound for the South and Midwest will choose to berth at the nearest port with the most efficient truck and rail routes inland, the report said. BCG and C.H. Robinson researchers say the biggest winners are likely to be ports in New York-New Jersey, Norfolk, Savannah and Charleston, which have been preparing with expansion projects to accommodate more traffic and larger ships.

While significant volumes of cargo are likely to shift their routes, the West Coast will hang on to the majority of trade from East Asia.

For many companies it may make sense to continue delivering through West Coast ports despite higher costs. Clothing companies, for instance, like to have current styles stocked as quickly as possible, and maritime routes to the East Coast take significantly longer. For them, it’s worth paying slightly more to get those goods faster.

Additionally, shifts in the strength of the dollar, occasional labor issues (on both coasts), increasing use of natural gas in ships, and the possible opening of a second Central American canal through Nicaragua could also push the destination of incoming goods back and forth from one coast to the other.