The 8.9 magnitude earthquake that devastated the north of Japan killing more than 10,000 people on Friday, could cost the country more than $3.4 billion a day in lost seaborne trade.
Tokyo Port and other southern ports are now operating normally after being suspended on Friday, while damage to northern ports is under assessment with authorities expecting some ports to remain closed for months or even years.
"Ports south of Tokyo are all operational, ports north of Tokyo are still under evaluation," a shipowner based in Tokyo told Reuters.
The country has began to assess the damage to port infrastructure, which will be vital in deploying aid and commodities to the regions worst affected by the quake.
Ports handling as much as 7% of the country's industrial output have been severly damaged by the quake, having a devastating effect on global supply chains as well as enormous financial costs, industry officials told Reuters.
"The short-term impact on economic activity could be greater than after the Kobe earthquake," Tokyo-based analyst with Nomura Securities, Jiyun Konomi, proclaimed in reference to the 1995 disaster which killed 6,000 people.
"Following the Kobe earthquake ... activity did not return to pre-earthquake levels within three months for freight transportation.," Konomi continued.
The ports of Hachinohe, Sendai, Ishinomaki and Onahama, medium-sized container facilities located in the northeast of Japan, are not expected to open for months after they suffered horrendous damage in Friday's quake.
"These ports will need a lot of time until they can be fully restored," said Tetsuya Hasegawa, Operations Manager at Heisei Shipping Agencies, Tokyo, told Reuters.
However, the larger container port at Kashima, suffered minor damage as did the smaller Port of Hitachinka, with both possibly being operational within a few weeks.
The tsunami that ripped through the coastline destroyed dozens of vessels, including three Kawasaki Kisen Kaisha's panamax ships, according to Reuters.
Oil shipments are expected to be delayed heavily so major port congestion is understandably expected: "Our channels indicate that crude currently en route to Japan will likely be discharged in India or elsewhere in Asia, with the refined products carried on to Japan once ports re-open," Michael Webber, an analyst at Wells Fargo Securities told Reuters.
Japan's grain shipments haven't suffered as greater loss as the industry is as of yet to be majorly disrupted by the quake: "Of Japan's some dozen major ports where bulk carriers or tankers can dock, only two are damaged, imports of grain to Japan therefore are not affected," Nobuyuki Chino, President of Unipac Grain told Reuters.