LoHud June 5, 2013 Written by Theresa Juva-Brown

From a giant crane hoisting steel beams to workers tightening bolts on an emerging platform in the river, the site of the new Tappan Zee Bridge was bustling with activity on Tuesday.

To promote the $3.9 billion bridge replacement, project officials took about a dozen members of the media on the river to see construction preparations. Leaders from Tappan Zee Constructors — the team designing and building the new bridge — and the Thruway Authority led the tour on a tugboat suitably named Tappan Zee II.

“This project is progressing and you’re going to see it ramp up over the next several months to the next year,” said Brian Conybeare, a special adviser to Gov. Andrew Cuomo. “More and more equipment arrives almost daily for this pre-construction work.”

The twin span is set to be completed by April 2018. Crews have just wrapped up test borings of the river’s soil and plan to start test pile-driving next month. Pile-driving tests are necessary to ensure that when permanent supports are installed, they are strong enough to hold the new span.

By the middle of next year, close to 100 work barges will fill the river, with about 30 of them being used to hold giant cranes, officials said.

There are about a dozen barges in the river now, with each dedicated to specific tasks. For example, one team is currently setting up vibration monitoring equipment on the existing bridge, while another is focused on building a 1,000-foot platform off the Tarrytown shore. When completed, the temporary trestle, which won’t be attached to the shore, will house a crane for construction.

“The new northern span will be right over our heads,” Conybeare shouted as the tugboat chugged parallel to the existing bridge on its way to the trestle location.

At the site, a 300-ton crane on a barge slowly lifted a hydraulic power unit that operates a vibratory hammer.

The hammer vibrates piles into the river bed, a technique that is less noisy than pounding them in, officials said.

In addition to the Westchester trestle, crews plan to build a similar one off the Rockland shore, though that one will stretch about 1,300 feet, Conybeare said.

Click here to watch the progress on The New NY Bridge:

http://www.lohud.com/apps/pbcs.dll/article?AID=2013306040075