We are moving up Manhattan and talking about the Brooklyn Bridge today. This iconic bridge is an amazing structure to visit and a must do when in New York City. I walked about halfway across the bridge on the central upper level dedicated to pedestrian and bicycle traffic. Below the walkway is six lanes for automobile traffic. I found the neo-Gothic towers to be amazing and display both the beauty and strength of the city.
What amazed me the most is that at the time it opened in 1883 it was the longest suspension bridge in the world and 50% longer than any previously built. It is also one of the oldest roadway bridges in America.
The bridge’s main span over the East River is 1,595 feet 6 inches. The bridge cost US$15.5 million in 1883 dollars (about US$403,339,000 in today’s dollars) to build, and an estimated 27 men died during its construction, which began in 1869. The bridge’s two towers were built by floating two caissons, giant upside-down boxes made of southern yellow pine, in the East River, and then beginning to build the stone towers on top of them until they sank to the bottom of the river. Compressed air was pumped into the caissons, and workers entered the space to dig the sediment, until the caissons sank to the bedrock. Once the caissons had reached the desired depth they were filled in with brick piers and concrete. The whole weight of the bridge still rests upon these constructions. Many workers became sick with the bends during this work. This condition was unknown at the time and was first called “caisson disease” by the project physician, Andrew Smith.
Washinton Roebling designed the bridge to be six times as strong as he thought it needed to be, which is one of the reasons the Brooklyn Bridge is still standing when many of the bridges built around the same time have vanished or been replaced.
I found it very interesting that the substructure of the towers have been used as a wine cellar and bomb shelter in the past. In fact Cold War era emergency supplies were found during an inspection in 2006.