Port of Charleston cranes for Wando Welch Terminal

Two 155-foot-tall cargo cranes built by ZPMC in China arrived at the Port of Charleston's Columbus Street Terminal on Sunday. They will be transferred to Wando Welch Terminal on Thursday for final assembly. Eventually, they will help move cargo boxes to and from big container ships traveling to the East Coast through the expanded Panama Canal. Provided/State Ports Authority 

As a vessel carrying two ship-to-shore cranes chugged toward the South Carolina coast last week, the State Ports Authority approved a bargain-basement deal for another pair of the massive structures that move cargo to and from container ships.

"We negotiated and got a really good cost of $9.5 million per crane," Jim Van Ness, the SPA's director of engineering, told the maritime agency's board of directors.

Van Ness said Shanghai Zhenhua Heavy Industries, better known as ZPMC, was experiencing a lull in its fabrication yard and needed the extra business. So, during a recent trip to the company's headquarters in China, Van Ness and his crane-making counterparts haggled over costs.

Van Ness said he thinks he got the better end of the deal.

"Typically, these cranes are $11 million or more," he said.

The board's approval to spend $19 million on the new cranes came just days before another order of the 155-foot-tall cargo movers arrived on Sunday at the Columbus Street Terminal in Charleston.

They will be transferred Thursday to Wando Welch Terminal in Mount Pleasant, where final assembly will take a couple of months.

The recently arrived cranes are part of a separate $23.6 million contract with ZPMC that the SPA board approved in 2016. They will join a pair of 155-foot-tall cranes at Wando Welch — dubbed Heavy Metal and CraneBob Blue Pants — that are already working ships hauling as many as 14,000 containers at a time.

The SPA's board of directors also approved a $69.5 million contract with ZPMC in October that will bring six more cranes to the Port of Charleston — one more for Wando Welch and five for the new Leatherman Terminal scheduled to open in 2020 on the former Navy base in North Charleston. The discounted cranes approved last week, which will be used at the North Charleston Terminal, will be added to that contract.

All told, the SPA will spend about $140 million with ZPMC for supersized cranes needed to service a growing global fleet of big container ships moving cargo to and from the East Coast through an expanded Panama Canal.

"They do 90 percent of the cranes" used in the maritime industry, Jim Newsome, the SPA's president and CEO, said of ZPMC. For seaport or terminal operators, "you're married to them — you're not just dating them," he added.

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Huang Qing-feng, president of ZPMC, called the company's relationship with the South Carolina maritime agency "a continued, long-term journey," adding in a statement that "we appreciate the relationship we've built."

The cranes are one part of a multibillion dollar capital improvement plan the SPA and others hope to complete in the next few years to lure more of the big ships — called neo-Panamax vessels — and their cargo to the Port of Charleston.

On Friday, politicians and others will mark the beginning of a $529 million project to deepen Charleston Harbor to 52 feet from 45 feet so the heavier ships can navigate the entrance channel regardless of tides.

The dredging, to be completed in phases, is expected to take between 40 and 76 months, depending on weather, the availability of equipment, funding from the federal government and other factors.

When it's completed, the Port of Charleston will have the deepest navigation channel on the East Coast.

The new Leatherman Terminal, at a cost of $762 million, is expected to open its first phase by the time dredging is completed. Other projects include a new road connecting Interstate 26 with the Leatherman Terminal, an intermodal rail yard at the former Navy base, additional equipment and strengthening the wharf at the Wando Welch Terminal.

Reach David Wren at 843-937-5550 or on Twitter at @David_Wren_