A shipping line that moves dozens of vessels and millions of dollars worth of cargo through the Port of Charleston each year has let its contract with the port expire.

Executives with Turkon America, a Turkish carrier service with U.S. offices in North Charleston and New Jersey, spent part of this week in Savannah, the port city that's giving Charleston a major run for its money when it comes to luring away lucrative cargo services and shippers.

South Carolina State Ports Authority officials said Friday they were still in negotiations with the shipping line and hope it will remain a port customer, but that its contract ran out at the end of April and has not been renewed.

According to waterfront businesses that serve ships docking in Charleston, Turkon America signed a contract Friday to take its business to Savannah.

Maritime leaders said Turkon is one of many shipping lines to have expressed growing frustration with congestion at Charleston-area terminals, and that its potential move to a competing port could cost Charleston businesses millions of dollars in revenue.

"For us, it would be a loss of revenue approaching six figures," said Robert New, president of Charleston Port Services.

New's company is the largest line-handling business serving ships that call on Charleston. "When we lose a (shipping) line, there's a ripple effect people don't see," he said Friday. "You factor in harbor pilots, stevedores, tug companies. This is a shot over our bow, and it highlights that we need to get in the trenches and fight for each one of these lines."

Turkon America has a branch office in North Charleston and, according to the ports authority's vessel schedule, moves one ship a week through the North Charleston Terminal. New said his company has worked on 15 Turkon vessels in the past 18 weeks.

Port marketing and sales chief Fred Stribling said the shipping line's annual frequency is less than that, with a few more than 30 Turkon ships passing through the port each year. A total of about 2,500 ships moved cargo through the state's terminals in Charleston, Port Royal and Georgetown last year.

"They're a relatively small customer, but every customer is a good one," said Ports Authority spokesman Byron Miller. "We've been in discussions with them for months about various issues. Every issue they've raised, we've sat down with them and tried to work with them on it."

Representatives at Turkon's North Charleston and New Jersey offices did not return phone calls. Shelley Drexler, accounting director for the firm's New Jersey headquarters, would not discuss the contract issues, but he confirmed that company executives were in Savannah Thursday on business.

Turkon currently has no service at the Port of Savannah, according to the Georgia Ports Authority's service schedule. Georgia port officials also did not return phone calls.

"This trend is what concerns us," New said. "It's deceptive because, while we're not losing the major lines, as they decide to expand, they're running those new services to Savannah. Five years ago, there were no Maersk (Sealand) vessels in Savannah. Now, all the major lines run there."

Charleston and Savannah have been running neck and neck in the amount of container cargo moving through the ports each year, with South Carolina barely edging out its southern neighbor as the fourth-busiest container port in the nation last year.

State lawmakers and port officials have recognized the need for the Port of Charleston to stay competitive. The Legislature is considering a bill that would give tax breaks to companies that increase their cargo shipments through the state's ports, an incentive that states like Georgia, North Carolina and Virginia have offered for years. Those states, unlike South Carolina, also funnel tax dollars to their public ports.

The ports authority also is seeking environmental permits for a new $600 million shipping terminal at the former Charleston Naval Base in North Charleston. That project is not expected to be completed for another decade, and officials expect existing terminals to reach capacity in a few years.

State Ports Authority chairman Harry Butler said the authority board was aware Turkon was in negotiations with the Georgia Ports Authority. He said Charleston port officials had expected to hear by Friday "whether they're going to accept the offer we have given them or if they're going to go to another port."

"I think it's the same issue that we always face," Butler said Friday. "All these lines realize that if they can make the same connections to the west ... it gets down to pricing for the services we offer. We think we've offered them a fair price."

Shipping lines, like all businesses, are sensitive to pricing changes.

South Carolina has in recent years imposed several service charges that other ports around the nation have not. Last year, the authority began charging customers a $2-per-container fee to pay for homeland security improvements at terminals. Dozens of other ports are only now starting to charge similar fees.

The ports authority also will start charging shipping lines a fee in June any time they keep loaded containers on port property longer than a week. The fee is meant to keep cargo moving quickly through crowded terminals that are rapidly reaching capacity. Again, similar charges are being phased in at other ports.

"We could cut our prices, we could give away free services, we could not charge them and let them leave containers on our docks as long as they want to," said Butler, a Georgetown real estate developer who's been chairman of the ports board since January. "But we don't have the capacity and the space to be able to do that, and we need to maximize the space we do have."

Butler said he thinks some shipping lines, especially larger carriers like Maersk Sealand, have been frustrated with congestion at the existing North Charleston Terminal. A renovation project there is months behind schedule and has reduced the amount of space for ships to dock.

A contractor hired to reinforce the steel dock supports at the terminal was supposed to have the three-part project wrapped up by early 2006. Port officials say they now hope to have at least the first phase of the project completed by the end of the year, and that a new contractor will be hired to finish the job.

"(Turkon) might have experienced some frustration with (congestion), but their ships are smaller ships and we've always been able to fit them in," Butler said.

Still, the shipping line's hesitation to keep its services in Charleston should send a message that South Carolina's ports need help to stay competitive, Butler said.

"This is part of what we've been telling people would happen if we don't get some new ports," Butler said. "This is why we've been trying to get lawmakers and the public behind the port, because those dollars (generated by shipping activity) go to the state, to the state's schools, and help keep things running."

Gary Santos, ports manager for Inchcape Shipping Services, said South Carolina needs to better coordinate its overall economic development agenda with plans for port development.

"We need distribution centers in the worst way," Santos said, referring to the large retail warehouses that are cropping up closer to Savannah than Charleston. The facilities are a major boost to ports as retailers like Wal-Mart, Toys "R" Us and Home Depot scramble to move cargo in from overseas.

"When (those kinds of) customers say, 'We want you to go here,' shipping lines listen," Santos said. "It's very easy to move ships around. You just point them in a different direction."