Here they come: all water services from Asia to the East Coast will increase during the next year.(Cover Story)

Shippers hankering for new ocean capacity can look forward to several new all-water alternatives to carry their cargoes from China and Southeast Asia to the U.S. East Coast ports. Container lines are lining up to add all-water services as soon as the current wave of shipbuilding expands the supply of vessels.

Cosco Container Lines expects to add an all-water service through the Panama Canal in August. China Shipping Container Lines is set to start one from China to East Coast ports via the Suez Canal in September. And in May, CMA CGM started a third all-water service via Panama to Houston and Savannah, primarily to handle Wal-Mart imports from China.

The additional capacity won't arrive a moment too soon. Outbound container capacity from ports in China and Southeast Asia is extremely tight, forcing carriers to "roll" cargo to later voyages. Peter Zantal, general manager of strategic analysis and industry relations for the Port Authority of New York and New Jersey, saw it firsthand when he and other port executives visited Chinese and Southeast Asian ports this spring. "They were rolling 20 percent of the cargo on every trip," he said.

The crunch should ease next year as dozens of large, new ships are delivered. Many of these vessels will bump older Panamax tonnage to other routes, including new all-water services through the Panama Canal.

Though the new services will ease constraints on vessel capacity, shippers could face other problems. The …