Caltrans is calling this next milestone kind of like the Super Bowl. Today, crews are putting in another section of the main tower. It's a slow and delicate process, with a lot of engineering and physics going into it.
Crews mobilized early Monday morning, getting everyone in place for this next big step. They will be working around the clock, for the next four days. They are adding another section to the single tower, self-anchored suspension bridge - the largest in the world. Basically imagine the tower being a stool, cut up in five different sections. Each section has four legs.
Today, the second section goes in. The first one went in this past July. The legs for the second section are each 107 feet in length, weighing over a million pounds.
So far, weather conditions have been perfect, but with another storm, just days away, Caltrans will be keeping an eye out for one thing.
"Wind is the probably the worst thing. If you can imagine if you got something that heavy and it starts catching the wind like a sail and starts moving around - we have got to slow down," said Caltrans spokesperson Bart Ney.
This next section is being hoisted up and placed down, basically at bridge level, so drivers will be able to see the action, but Caltrans warns they should keep their eyes on the road, especially since it's happening near the S-curve. The third section will be arriving in December.
After all five sections are put in the tower will soar 525 feet in the air. The entire eastern span will be complete in late 2013. The cost so far is about $5.4 billion.