Bridge-Tunnel in , honoring the local civic leader who is credited with making the bridge-tunnel become a reality. Kellam was the chair of the Chesapeake Bay Ferry Commission while it existed. He became the first chair of the Chesapeake Bay Bridge-Tunnel Commission in , and held that position until retiring in Despite the official name change, all signs and publications continue to refer to the Chesapeake Bay Bridge-Tunnel.
The combination of bridges and tunnels crosses Between the toll plazas on the north and south ends, the bridge-tunnel is 20 miles long. Counting the approach roads, the facility is 23 miles long. Each of the underwater tunnels is over one mile long, and the entire project is a major engineering achievement. The bridge spans, 30' high above the water to avoid wave action and to allow small boats to pass, are supported by 4, concrete pilings driven into the sediments at the bottom of the Chesapeake Bay.
The longest piling was driven ' deep. The pile driver was a special machine known as Big D, with steel legs that could be jacked up by compressed air. During the Ash Wednesday storm in , the Bid D could not be raised higher than the waves. The legs snapped, causing extensive damage. After driving the piles, they were cut at the top to ensure a flat and consistent surface. Three piles were held together at the top by a concrete cap, creating a "bent" to support the bridge decks installed at the end of the construction process.
Cutting the pilings to the correct height and installing the horizontal "bent" was done by a unique machine known as the Two-Headed Monster, built solely for that purpose. Bedrock at the mouth of the Chesapeake Bay is over 6, feet deep, so the pilings are supported solely by accumulated sediments.
Test drillings identified where the sand and clay were most compact, most capable of keeping the pilings in place. The curves in the bridge were designed to take advantage of the best soil conditions. All of the precast concrete pilings and other materials were manufactured at the new Bayshore Concrete Products plant at Cape Charles.
It was established initially for the project, and continued in business producing concrete materials for other major projects until closing in Had the company won contracts to supply concrete for the expansion of the Thimble Shoals tunnel, it might have stayed in business even longer. However, it was not successful in winning a contract to supply concrete products to the second tubes of the tunnels for the Chesapeake Bay Bridge-Tunnel and Bayshore Concrete Products then closed down.
Coastal Precast Systems, which won the contract, was located in the City of Chesapeake. It bought the Cape Charles facility and re-opened in The bottom of the Chesapeake Bay is owned by the state of Virginia. The Thimble Shoal tunnel crosses the old channel of the James River. The US Navy relied upon that deep channel for its warships to access the Atlantic Ocean, and objected to any bridge across the channel.
In warfare, an enemy might destroy the bridge and block the Thimble Shoal channel. That could bottle up the Navy's ships inside Chesapeake Bay and prevent ships in the Atlantic Ocean from reaching the massive naval base at Norfolk. Ships going to Baltimore used that route, and Maryland officials insisted upon a tunnel to ensure that channel would always be open to maritime traffic. Even further north near Fisherman's Island, the bridge is elevated to allow small vessels to pass underneath.
That enables them to avoid going the extra distance to the Chesapeake Channel, and reduces the traffic congestion there. The tractor-trailers crossing the elevated bridge sections inevitably encounter the gulls, other seabirds, and even peregrine falcons that constantly fly around the mouth of the Chesapeake Bay.
No technique has been developed yet to keep the birds from flying near the deck of the bridge, though waving banners and even walls have been considered. It is common to see bird carcasses on the bridge-tunnel, victims of high-speed collisions; thousands of birds die annually.
One observer noted: 6. I have seen large tractor trailers hit an entire flock of tree swallows and kill dozens and dozens of birds in one hit. Tunnel sections were prefabricated in Orange, Texas as foot long, foot in diameter steel tubes. For each tunnel, 37 sections were required. The ends were sealed so the tubes would float, then they were barged to Norfolk.
Two of the airtight cylinders broke free from the tugs in the Gulf of Mexico. Both were recovered, though one had washed up on a Texas beach first. At Norfolk, a two-foot-thick concrete shell was added before the sections were towed to the construction site and lowered into a trench previously excavated in the bay sediments.
Once in place, tube sections were welded together and the connections were sealed with a coating of concrete, before the waterproof caps on the ends were removed. The final roadway inside the tube is feet wide, plus a sidewalk less than 3-feet wide on one side. The tunnels connect to the bridge spans at four artificial islands, at either end of the Thimble Shoal Channel and the Chesapeake Channel.
Massive granite boulders, each weighing between tons, were brought by rail from the Kenbridge granite quarry in Lunenburg County. The boulders were barged into the bay, then dropped to the bottom to form a ring larger than four football fields. Sand and gravel was pumped into the interior of the ring, and then another layer of boulders was added to raise the height of the column.
At the surface, enough boulders were used to create a protective rip-rap that blocked erosion from even hurricane-induced waves. Funding the bridge-tunnel required the General Assembly to change its traditional approach for funding highways.
The Commonwealth of Virginia had followed a "pay as you go" approach since passage of the Byrd Road Act, but starting in substantial Federal funding to construct new highways became available. Local leaders on the Eastern Shore and in South Hampton Roads recognized that they would not obtain funding from the state or Federal sources soon, and obtained the state legislature's permission to sell bonds to finance the bridge-tunnel project.
It is managed by the Chesapeake Bay Bridge and Tunnel Commission, an member commission appointed by the governor to represent eight local jurisdictions and the state. The governor also appoints one member to represent the state. The district includes two members from the Peninsula cities of Newport News and Hampton, showing how the bridge-tunnel was expected to have region-wide economic and transportation impacts.
Only four of the 11 members on the commission come from the Eastern Shore counties, Accomack and Northampton. As a political subdivision of the state, the Chesapeake Bay Bridge and Tunnel District operates its own police force. All fines are paid into the state's Literary Fund, so there is no incentive for the district to operate a "speed trap. The commission was authorized to issue revenue bonds, which had to be repaid through tolls.
Selling the bonds raised the initial money required to pay contractors to build and manage the new structure. Because the bonds were not backed by a guarantee of funding through local property taxes or the general revenue of the state, the "full faith and credit" of Virginia was not put at risk. The Commonwealth of Virginia provided no construction money to build the initial bridge-tunnel or to expand it, though the state does provide urban street funding now for maintaining the transportation facility.
The new bridge-tunnel provided a mile shortcut for traffic headed north to Delaware and New York compared to I, which was also completed in the mid's. Despite the shorter distance, the better-quality road and faster speeds on the interstate attracted most of the traffic. Commercial businesses on the Eastern Shore, including poultry plants, continued to ship primarily to customers towards the north rather than use the bridge-tunnel to ship to customers in Hamton Roads or to export products through the Virginia Port Authority terminals.
The lack of business affected the financing for the project. In , the commission defaulted on the "Chessie C" series, because traffic projections had been too optimistic and toll revenues were inadequate to pay bondholders what they had been promised. In , revenues had increased, past due interest was paid, and the commission's credit rating improved. In , the Fitch bond rating agency affirmed the A- rating for roughly half of the outstanding bridge-tunnel bonds, and noted: The district's bridge and tunnel facility is monopolistic in nature, serving as the only linkage between the metropolitan Hampton Roads region and Virginia's eastern shore.
Volume has been relatively stable, growing at a 0. Building Time: -Northbound: 42 Months — Construction began on September 7, , and the project was opened to traffic on April 15, No tax dollars were used. Trestles: -Length Tunnels Trench Type : -Thimble Shoal Tunnel: 5, feet in length, portal to portal -Chesapeake Channel Tunnel: 5, feet in length, portal to portal.
Construction is underway on a parallel tunnel at Thimble Shoal Channel. Click here for more information on this project. The Chesapeake Bay-Bridge Tunnel is a modern feat of engineering but it's also considered to be one of the scariest roads - or bridges, technically - in the country. For those who have a fear of heights, open spaces, or open water, it's not destined to be the more thrilling of experiences. However, depending on your take about having the chance to drive across what was once considered one of seven global engineering wonders, it can also be a truly humbling experience.
When travelers come up to this extensive water crossing, it's more akin to looking at a giant concrete serpent that's snaking through the water, all the way to a sight unseen. It's easy to imagine the bridge itself coming alive to take on some form of a sea monster that resembles Loch Ness, with each rise and fall of the bridge being a hump on the monster's back. In reality, it's a mix of concrete, cement, asphalt, and steel that make up this immoveable giant, and it truly is a masterpiece.
The bridge itself is not very wide and allows only enough room for two passing lanes of cars, with two, two-lane bridges running parallel to each other, side by side, for almost 20 miles. It's the kind of bridge that you don't want to get caught on during windy weather or a rainstorm and especially not in traffic which does happen. As opposed to a suspension bridge, the Bay-Bridge Tunnel doesn't have the height of other bridges, making drivers feel as though they're driving just over the surface of the water with not much distance between their cars and the lapping waves below On a clear, sunny day, the drive across the bridge is absolutely stunning.
However, there are also two tunnels that make up parts of this bridge, each just over a mile long in length. These tunnels were built to allow cargo ships to cross, as shipment in and out of this bay is too frequent to permit only a bridge.
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