Cargo containers at Wando Welch (copy)

The Port of Charleston set a record for containerized cargo moving through its terminals in fiscal 2018. Provided/State Ports Authority

Shuttling shipping containers around on barges might save the State Ports Authority big bucks. It works in other big harbors, New York, the Chesapeake Bay, the European ports of Antwerp, Rotterdam and Amsterdam. Netherlands-based Port Liner even produces autonomous, all-electric container barges.

The SPA is looking at the option primarily between Wando Welch Terminal and the under-construction Hugh Leatherman Terminal on the Cooper River in North Charleston where a truck-and-rail hub is being built. That would take thousands of short-haul truckers off the road, cut pollution, create efficiencies and ultimately save money — in theory.

Federal money is available for port modernization projects, and old-tech barging, which qualifies, might have a place here. Of course, a rock-solid cost-benefit study is needed — something a federal grant should pay for. And the SPA should go after all available federal funding before spending its own money while exploring options.

Weighing some of the benefits and costs might be tricky. For instance, what’s the value of 1,000 fewer truck trips per day on Interstates 526 and 26? What about the loss of short-haul trucking jobs vs. the creation of barging and longshoreman jobs?

The SPA will need to think the concept through carefully, along with numerous other agencies that would be required to sign off on such a plan. The truck-and-rail hub is scheduled to open by 2021, about the same time as the Leatherman terminal. Barging advocates say it’s more fuel efficient than short-haul trucking. And some container barges and tugs run on clean-burning liquefied natural gas.

Barging would mean added infrastructure in the upper harbor, perhaps 700 feet of wharf space on the northern side of Wando Welch and something similar on the receiving end at Leatherman. So far, there’s no ballpark estimate for what that might cost. You’d also have regular barge traffic in both rivers and around Daniel Island. What would that look and sound like?

The added dock space at Wando Welch would jut into a marshy triangle bounded by I-526, an apartment complex, a gym and a few light-industrial businesses. It would require bringing in more than 1 million cubic yards of fill material and 25,000 cubic yards of rip-rap and stone along the Wando waterfront for support, The Post and Courier’s David Wren reported recently.

SPA Chief Operating Officer Barbara Melvin told Mr. Wren the SPA has applied for permits for the wharf extension at Wando Welch and would soon start talks with community groups about the project’s impact.

“We think there are great benefits that should be realized … among the community, the environment and operationally,” she said.

About 210,000 containers delivered to Wando Welch are trucked to rail yards now. That number is expected to grow to 350,000 over the next 30 years.

Certainly, the SPA must stay competitive and find efficiencies wherever it can. And our broad rivers could shoulder a significant amount of inter-port container traffic. But we must make sure the burden we’re shifting is lighter on the wallet as well as the roads.