Construction is moving forward on the new Tappan Zee Bridge and the second stage of dredging the river is starting this week.

The new span is starting to take shape as 400-foot, 1,100-ton girders continue to be put in place by the "I Lift New York" super crane. The huge beams sit atop 14-foot thick concrete foundations that can be seen on the river alongside the current bridge.

As the beams continue to be sent down the river from upstate, more dredging is starting up this week. By removing sediment from the bottom of the river, the water level will deepen and make way for the super crane that will be used to take down the old bridge.

The dredging can only be done from August to October in specific locations and will be conducted 24/7 because there is such a short window. The reason for the small window is to protect the migration and spawning patterns of fish.