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Ben Franklin Bridge

First official name name: Delaware River Bridge. Officially became the Ben Franklin Bridge at its dedication in 1956.

Bridge was opened to traffic at midnight on July 1, 1926. President Calvin Coolidge officially dedicated the bridge on July 5, 1926.

For three years it was the longest suspension bridge in the world. It was beaten by 100 feet when the Ambassador Bridge in Detroit opened in 1929.

In the late 1800s, a narrow, mile-long island was removed from the Delaware River, clearing the way for the first uninterrupted ferry service between Camden and Philadelphia, as well as a slew of bridge designs planned to connect the two cities. The midpoint of the island was just about even with Market Street. Much of the islandís soil was taken to League Island and used for ground fill for the Philadelphia Naval Yard.

Before the bridge, people would wait for hours and hours, in long lines of traffic, creeping toward the ferries that would take them across the river. Imagine all the traffic being loaded onto boats on a hot trip home from the Jersey Shore!

In 1919, New Jersey and Pennsylvania legislatures created the Delaware River Bridge Joint Commission. Each state would pay half of the construction costs. Land acquisition in each state would be that stateís responsibility.

September 24, 1920; Ralf Modjeski is named chief engineer.

Original cost estimate was $29 million. Final cost was $37,103,765.42

Old St. Georgeís Church on Fourth Street -- originally on the demolition list -- became known as the church that moved the bridge, as a group of angry protesters convinced the Joint Commission to deflect the bridge slightly southward, missing the church by a mere 14 feet!

On September 29, 1921, all bridge plans were approved by the Army Corps of Engineers and the Secretary of War. Pier and anchorage land was condemned a week later.

Parades in Camden and Philadelphia marked the start of construction on January 6, 1922. Mounted police, Governors, Mayors and other dignitaries, as well as bands, floats, a giant model of the bridge towed by a truck, and a 17-gun salute from the cruiser Olympia, all helped celebrate the day.

The two piers that support the towers are made of solid concrete resting on bedrock. Granite blocks cover the top third of the piers so that even if the tide is very low, the concrete is never exposed.

The Philadelphia tower pier is eighty feet tall, with only about a third of the structure visible above water. The river bed is deeper on the Camden side so that tower pier is 113 feet tall. The result is that the pier tops are level and appear identical from above the water.

Sand hogs were men who worked in pressurized chambers, digging through the river bottom in order to help settle the piers onto bedrock. If they ascended from their pressurized chamber too quickly, they exposed themselves to an excruciating, and potentially deadly condition called ìcaisson diseaseî or ìthe bends.î This is caused when a sudden decrease in air pressure around a personís body causes nitrogen in the blood stream to bubble. Extreme pain and loss of muscle control is the result.

Due to high air pressure in the chamber, sand hogs were unable to force enough air out to whistle while they worked.

Concrete workers on the Camden bridge anchorage project were paid 40 cents per hour.

Each cable tower is 350 feet tall and was built to support its own freestanding weight with no other support. The towers reach 380 feet above water level. Each tower is made of 5000 tons of steel. Flexible silicon steel was used for the columns in order to allow the towers to respond [by flexing] to unbalanced cable pull.

Each tower is bolted and glued to its pier by 80 anchor bolts, some nearly fifteen feet long!

There is more than 25,000 miles of wire in the two main bridge cables, enough to circle the earth at the equator. Each main cable consists of 18,666 individual strands of wire, has a diameter of thirty inches, is 3550 feet long, and weighs almost 3400 tons.

The first person to cross the span from one shore to the other was a construction worker named George C. Morgan. The Blackwood, New Jersey resident did so by trekking across a cable footbridge that was being built. The footbridge hung in the same position that the main cables would eventually hang, and was built to allow workers to access the main cable as it was being constructed. The wooden flooring on the footbridge was still incomplete when Morgan made his trip, requiring that he traverse the final 50 feet on the bare footbridge cables. At this time, there were no main cables, no bridge floor, and no pedestrian walkways, just the cable footbridge draped from anchorage to anchorage, up and over the towers, nearly 400 feet above the river.

There were originally six toll houses with ten collection booths on the Camden side of the bridge.

When the bridge opened, there were no posted speed limits on it. Drivers were expected to use ìCommon senseî instead.

Total length including plazas is 9,620 feet.

32,000 vehicles passed over the bridge in the first 24 hours that it was open.

Tolls When the Bridge Opened

Car or taxi 25¢
Bus (pneumatic tires) 40¢
Bus (solid tires) 50¢
Trucks (variable) 25¢ - 75¢
Motorcycle or bicycle 10¢
Horse-drawn vehicle
one or two horses
30¢
three or more horses
40¢
Horse and rider 15¢
Led horse, mule, cow, hog or sheep 20¢
Pedestrian free

 

Other resources

The Delaware River Port Authority