The Piers & Towers
Around the location of a pier, blocks of reinforced concrete, called anchors, were towed into place on barges and then dumped into the water.
The first section of the pier, the hollow caisson, was towed into place. To hold the caisson in position, divers secured it to the underwater anchors. Creating the pier was a gradual process, building up with steel and concrete onto the caisson. Slowly, the pier "grew" upward and sank downward.
Eventually, the caisson's steel cutting edge met and sunk into the earth. The pier was then excavated to the proper depth through its hollow core. Heavy concrete sealed the bottom, then a broad concrete pedestal capped the top. A timber fender was added to deflect debris and traffic.
Towers were erected on each pier pedestal and finished with a steel saddle on its highest point to receive the main suspension cable.
The Suspension Cables
Temporary catwalks were placed from tower to tower enabling crews to work on the cables in the air. The two main suspension cables were spun from wire spools unreeling onsite and affixed to an anchorage built on land at each end.
Individual suspender cables, also called hanger ropes by their manufacturer, were hung at the prescribed intervals along the length of the two main cables. These hung in the air until attached by zinc "jewels" to sections of the deck.
Building the Deck
For the first bridge, the deck was constructed with pre-formed steel sections. They were carried to the bridge on scows, then lifted up and attached to the cables.
The deck for the second bridge was built very differently than for the first. Steel beams were raised singly or in sections.
Piece by piece, like a giant tinker toy, the deck was assembled. When all the steel sections were riveted into place, the deck was ready to receive its concrete surface.
