The Baltimore waterfront isn’t as industrial as it used to be, but even newcomers know this is a port town, where international shipping helps power the local economy. You can see the working cranes from the luxury harborfront condos.

But what is “ro/ro” and why do we need a 50-foot shipping channel? Many of us have heard a distinct, and foreign, language in the past week since a cargo ship toppled the Francis Scott Key Bridge, killing six construction workers and halting port activity.

As news continues about the tragedy, let’s pause and define some terms.

What is the Port of Baltimore?

The port was founded in 1706 and renamed in 2006 for the former U.S. Rep. Helen Delich Bentley, who was also a Baltimore Sun reporter and a port consultant.

It not a single entity but a collection of marine terminals, which are individual waterfront sites where cargo ships dock along the Chesapeake Bay and branches of the Patapsco River.

There are the publicly owned terminals — which include Seagirt, Dundalk, North Locust Point, South Locust Point, Hawkins Point and Masonville/Fairfield — that are overseen by the Maryland Port Administration, part of the Maryland Department of Transportation.

There are also several private terminals. Public and private terminals typically focus on specific cargo but also can compete for business.

What cargo comes and goes?

Most familiar might be those 20- or 40-foot long metal containers, measured in TEUs or twenty-foot-equivalent units, that are stacked by the thousands onto cargo ships.

Many are filled with goods to fill our online orders from Amazon and other retailers. They go directly on and off trains and trucks at the intermodal transfer facility at Seagirt Marine Terminal on Broening Highway.

Other public terminals handle automobiles and ro/ro, short for roll-on/roll-off, which includes farm and construction equipment that can be driven off ships on their own power, rather than lifting them with a crane. The also handle break-bulk cargo, shipped in a box or on a pallet, such as steel and paper products.

There is also a public cruise ship terminal at the South Locust Point Marine Terminal that takes passengers to destinations including the Caribbean and New England aboard Royal Caribbean, Carnival and soon Norwegian cruise lines.

Private terminals handle steel, paper products and automobiles, as well as bulk cargo, or loose, products that need to be scooped in and out of the hull of a ship, such as coal, salt or sugar. Tradepoint Atlantic, home to several distribution warehouses, is building an operation to take containers right off ships.

Collectively, the port terminals handled 55.5 million tons of import and export cargo in 2023, according to the port administration.

Who works at the port?

Dockworkers at the public terminals in Baltimore are called longshoremen, 2,400 of which are represented by the International Longshoremen’s Association.

Another name for longshoremen is stevedores, though technically stevedores are the dockworker managers. They all have specialized training to load and unload the ships, operate cranes and other heavy machinery, do repairs and perform administrative tasks.

The port administration reports more than 20,000 jobs are directly tied to the port, with 60% of workers living in Baltimore or Baltimore County. Among them are also truckers, tug boat operators and freight forwarders, who handle shipping logistics.

The port estimates there are 273,000 jobs indirectly tied to the port, including salespeople, mechanics, telecommunications workers and others.

According to a 2023 economic impact report prepared by Martin Associates for the Maryland Port Administration, the port generated $5.3 billion in wages for state residents, $647 million in state and local taxes and about $3.9 billion for businesses providing maritime services.

Once all the spin-off activity is considered, the report estimates the total economic value to the state from the Port of Baltimore is about $70.3 billion.

How does Baltimore fit into the supply chain?

Baltimore has made a name for itself in automobile and ro/ro cargo, handling more of this cargo than any other U.S. port.

Much of it has to do with geography. It’s the western-most East Coast port, an important distinction for cargo like farm equipment that’s headed to the Midwest and not protected by a container. Less time on a truck might reduce the risk of damage.

Cars and trucks, some 847,000 last year, go to dealerships in the Baltimore-Washington market, as well as north to Maine, south to North Carolina and west to Colorado.

Longshoremen here learn proper handling from the manufacturers during the port’s annual “Ro/Ro Rodeo.”

The locale, however, hasn’t always been an advantage. It’s a day’s trip up the Chesapeake, off-putting to shippers who would rather get their containers onto trucks and trains faster. Baltimore boosted its competitiveness more than a decade ago when it partnered with the private terminal operator Ports America to invest in a deeper channel and 450-foot, ultra-large neo-Panamax cranes to accommodate the biggest ships that go through the Panama Canal.

What happened to stop ship traffic?

In normal times, the main channel (the ships’ pathway on the river to the terminals) must be regularly dredged by the U.S. Army Corp of Engineers to remove mud and any debris down to a 50-foot depth so larger ships, carrying 10,000 or more of those TEUs, can navigate without running aground.

The problem now is steel from the Key Bridge is blocking the main shipping channel, cutting off every terminal, except Tradepoint Atlantic. Some cargo has been sent there, but the majority is being temporarily diverted to other ports.

Two alternate channels have been opened by the captain of the port, the Coast Guard commander in charge of the port’s safety and security. At 11 feet and 14 feet deep, they can’t accommodate cargo ships, but could likely accommodate a barge with about 1,500 tons of coal.

Who navigates through the channel?

When the ship rammed the bridge, it was being steered by a pilot from the Association of Maryland Pilots, or bay pilots. In the Port of Baltimore, these highly trained navigational guides are required on ships in the channel. The thinking is that ships operated almost entirely by foreign crews may be unfamiliar with the terrain.

Tugboats assist the ships while they are close to the terminals.

Those boats had just finished escorting the Dali, a 984-foot-long ship carrying about 4,700 containers for the Danish shipping giant Maersk, when it hit the bridge. The ship had lost power and the pilot was unable to steer.

The pilot was able issue a mayday warning to dispatchers, which authorities said gave police enough time to stop bridge traffic and save lives.