lift span placed
The structural steel span that will serve as the lift section for the Sarah Mildred Long Bridge was floated in and installed last Wednesday. As installed it weighs approximately 3 million pounds. Once it is completed - with a paved road surface and railroad tracks down the center - the span will weigh approximately 4 million pounds or 2000 tons.
I find the method of span placement to be fascinating. And I'm amazed at the minds that have the capacity to design a structure like this one.
Channel Closure Scheduled to Begin October 17th
Beginning on Tuesday morning the navigational channel will be closed to all vessels - from kayaks to tankers - within a 300-yard radius of the bridge. The nearly 3 million pound center lift span will be floated in on barges across the Piscataqua River between 10:00 a.m. and noon and positioned for the float in.
On Wednesday morning, between 6:00 a.m. and 9:00 a.m. the rising tide will lift the span to clear the bearings. Between 9:00 a.m. and noon the lift span will be put into position over the bearings. At 1:45 p.m. the outgoing tide will lower the lift span onto the bearings. Once resting on the bearings, the barge will be pushed to the state pier. Adequate clearance to remove the barge from under the lift span should occur at approximately 3:45 p.m.
published on the Sarah Mildred Long (SML) Bridge Replacement project web page
The Coast Guard has closed the Piscataqua River around the bridge until 6 AM on October 27th. I assume that's the time that is needed to connect the lift span to the pulley system on the towers that will raise and lower the bridge.
While I wasn't there for the float in I felt a need to see the bridge in progress. Today was a good day for a Portsmouth visit and bridge sighting! I'm lucky that the Memorial Bridge includes sidewalks; it was a good place to stand for an unobstructed view of the new bridge.
Looking inland, the lift span is currently sitting at the level of the railroad tracks.
The green bridge in the background is the I-95 bridge.
It's a little easier to see the lift span when looking to the sea.
