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The Bayonne Bridge is an arch of steel that swoops up from Staten Island and alights, about seventeen hundred feet later, on Bergen Point, at the southwestern tip of Bayonne, New Jersey. The arch supports a roadway that goes through it like the slash through a cent sign. Of all the city’s bridges, the Bayonne Bridge is the most powerful and intimate work of modernist-era art. Nothing half as tall stands near it. Sky fills the girders’ interstices and geometries, and above the arch the clouds rise dramatically. The bridge spans the Kill Van Kull, a body of water about two thousand feet across at its widest and about eight hundred feet at its narrowest. It is the color of lead and looks beat-up and hard-used.

Just past the bridge, the Kill Van Kull makes a sharp right into Newark Bay. Almost all the cargo that comes into the Port of New York and New Jersey unloads at the docks in Elizabeth and Newark, on the west side of the bay. Docks in Manhattan and Brooklyn used to handle most of the port’s cargo, but they had no room to store the huge accumulations of eight-by-eight-by-forty-foot containers employed in shipping today. New Jersey’s coastal flatland stretches for miles, and the vast container fields of Elizabeth and Newark are unpeopled cities in themselves, with their long, echoing canyons of containers stacked high. Ships that want to unload or load there—that is, almost all the cargo ships that come to the Port of New York—must pass under the Bayonne Bridge.

When it was built, in 1931, the bridge had a maximum vertical clearance of a hundred and fifty-one feet. In the mid-two-thousands, officials at the Port Authority of New York and New Jersey, which manages the port as well as other metro-area bridges, tunnels, airports, and highways, realized that the enormous new container ships scheduled to come into service in the near future were not going to fit. The superstructure of these ships tops a hundred and ninety feet. Port Authority planners considered tearing down the bridge and replacing it with a tunnel or a new, higher bridge. Eventually, they decided to keep the existing bridge and to raise its roadway by sixty-four feet. This they would do by building a new roadway higher up through the arch, then removing the old roadway.

The beauty of the bridge influenced their decision, as did the fact that it’s a National Historic Civil Engineering Landmark. Steven Plate, the Port Authority official who oversaw the latter stages of construction, compared his job to restoring the Sistine Chapel ceiling.

From where I live in New Jersey, it’s about twenty-five miles to the bridge. After I heard about the road-raising, I began to drive over there every so often to see how it was coming along. Watching construction gives me a sense of personal accomplishment, and all I have to do is show up. By the foot of the bridge on the Bayonne side there’s a city park that provides a good viewing point—you pull into the parking lot and the sight of the bridge fills your windshield. I always get out and walk around. At a well-situated bench I listen to the machinery on the bridge, the shouts of the workers echoing in the steel beams, the hammering of metal on metal, and the beeping of lifter-arm vehicles backing up.

Ships of all kinds, from tugs to tankers to police boats to container ships, go by on the Kill Van Kull. Sometimes they are in a slow-moving line, and one tug will become impatient and pull out and pass another. Canada geese and gulls and mallards land on the water, but the traffic is always scattering them, or the non-stop wakes shake them loose. The name Kill Van Kull may mean something like “the channel that comes from the bay.” The Middle Dutch word kille means “channel” or “stream,” but the K.V.K. (as people who travel it regularly refer to it) is, more precisely, a strait; its three miles connect Newark Bay with the Upper Bay of New York Harbor. As it continues around Staten Island, the K.V.K. merges into the Arthur Kill, another strait, which connects to the ocean on that island’s southern end.

Clashing tides from two directions meet beneath the bridge, and soon after a ship goes under it the pilot must finesse the turn of a hundred and twenty-seven degrees into Newark Bay; meanwhile, Staten Island’s shoreline, close by on the left, narrowly confines the ship’s stern. The maneuver is like carrying a dining-room table through a bedroom door while stepping on slippery carpets. In fact, these thousand-plus yards of the K.V.K. may be the trickiest passage in any major port in the world.

Accidents used to happen here all the time. The rock ledges under the water obtruded near the channel, and going aground was not hard to do. Hundreds of thousands of gallons of oil and gasoline have been spilled here. From the fifties to the mid-sixties, twenty-three accidents occurred in the vicinity of the bridge. On June 16, 1966, the Texaco Massachusetts was coming out of the bay and turning into the K.V.K. when it ran into the Alva Cape, which was carrying 4.2 million gallons of naphtha from India. (Naphtha is a solvent used in dry cleaning.) The naphtha gushed out and then ignited, killing men on the tug alongside. Bodies were floating in the water, and it took fireboats eight hours to extinguish the blaze. Thirty-three men died in the accident; it was the second-worst loss of life ever to occur on a New York waterway. Afterward, as workmen at Gravesend Bay were pumping out the Alva Cape’s remaining naphtha, it blew up again, killing four more. The Coast Guard had the deadly hulk towed far offshore and then sank it with barrages of artillery fire. It went down still flaming.

New York was once the busiest port in the world, but for decades the Port Authority turned its attention away from the waterfront, to new highways and real estate like the World Trade Center. By the early two-thousands, the port had fallen to fifteenth busiest in the world and third in the country (after the West Coast ports of Long Beach and Los Angeles). In 2004, not wanting it to slide further, the Port Authority, with the Army Corps of Engineers, began a $2.1 billion dredging project of the port’s major channels, all the way to the start of the Ambrose Channel, twelve miles out at sea. The project took twelve years and involved scores of dredges: blowing up massive amounts of submerged rock, digging hundreds of millions of tons of rock, mud, and sand, and putting the contaminated spoils under future luxury golf courses and in other ingenious places.