The official name is the Sarah Mildred Long Bridge. The original bridge was built in 1940 between
Portsmouth, New Hampshire, and
Kittery, Maine. It was built as part of a bypass to relieve the traffic on US-1 and the
1923 Memorial Bridge. The bridge also supported a Boston & Maine branch to South
Berwick, ME. The Guilford Rail System/Pan Am/B&M branch has been cut back and now supports only the
Portsmouth Naval Shipyard (95 photos). It also carried the traffic of I-95 across the river between 1960 and 1972 when the
Piscataqua River Bridge and turnpike extensions were finally opened to carry road traffic high above the river with three lanes in each direction. The I-95 bridge is the steel arch bridge you see in the background of the following street view.
A replacement bridge was scheduled to be opened in Sept. 2017, but the old bridge was scheduled to be closed in Nov. 1, 2016. The old bridge must have been in really bad shape to plan forcing road traffic to use the interstate after
the last train crossed it on Dec. 9, 2015. It was "carrying two loaded spent nuclear fuel flasks from Kittery Ship Yard en route to Idaho." [Bridge Hunter] But the lift span broke in August, 2016. Rather than spend the estimated $1 million to repair it, they just closed it a couple of months earlier than originally planed. Design of the new bridge started in 2013 and construction started in January, 2015. [
MDOT]
[
Wikipedia]
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Street View of the building of the piers for the replacement bridge. |
In addition to a lift span, the old bridge had a retractable steel girder span for the railroad deck that could let recreational boats pass without stopping road traffic. Because the railroad is used once in a blue moon to transport nuclear material to the ship yard, the retractable span that we see on the left side of the street photo below is normally open. That girder span was designed to raise up and then roll back into the truss. I included the "bridgeRare" label because of this span.
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Street View of the retractable girder span as well as the lift span. |
Now we turn our attention to the replacement bridge. The new bridge appears to use box girder concrete sections. Note the railroad deck has more piers than the road deck needs. But the extra piers are simple column piers.
An artists' view from I-95.
The second bullet point below explains why the lift span does not have two decks. The lift span is effectively designed for "street running" and is shared between the two decks. It is, of course, normally at the road deck level.
Key Bridge Attributes
- New bridge alignment improves marine navigation by straightening the navigational channel, allowing larger ships to access the port and shipyard.
- With a larger 56’ vertical clearance in its “resting” position, there will be 68% fewer bridge openings. In the normal operating, “resting” position, the bridge’s lift span is at its middle level, allowing motor vehicles to cross the river. The new bridge’s movable “hybrid” span lifts up to allow passage of tall vessels and lowers to railroad track level for trains to cross.
- 200’ tall precast concrete towers will support the 300’ long streamlined structural steel box girder lift span.
- New bridge layout uses eleven (11) fewer piers than the existing bridge, also improving the gateway span leading into downtown Portsmouth by eliminating an existing median pier.
The use of one lift span that can carry both road and rail traffic and that can be positioned at three levels --- open, road traffic, and railroad traffic --- also justifies the "bridgeRare" label.
This is the Facebook posting that provided the name so that I could learn about this bridge.
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Dinner with a view. [In the case of Jim, the view is the many cranes.]
Sarah Mildred Long bridge I worked there for a year and a half.
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Below zooms into the towers and the part of the railroad deck that is not completely obscured by crane barges. I'm sure the lift span is being built offsite and will be floated into place when the towers are ready for it. It looks like the towers are done except for the mechanical enclosure and equipment at the top. It appears from the concept art that the counterweights will be hidden in the towers.
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At Facebook resolution |
Update:
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MLC 300 making it look so easy
[The sheaves are 20-feet in diameter.]
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Curt Seeliger
posted two photos with the comment: "
Soon to be un-abandoned, the rail link to The Portsmouth Naval Shipyard in Kittery, Maine as a New Route 1 Bridge to Portsmouth, New Hampshire is opening soon"
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1
Railroad tracks soon to be installed on the Bridge's lower level. Kittery, Maine. |
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2
Soon to be connected rail link to the Portsmouth Naval Shipyard. |
Sarah Mildred Long Bridge Replacement Project
posted three photos with the comment: "
Some aerial photos of the bridge from Saturday, courtesy of The US Coast Guard."
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1
MLC 300 with vpc on barge. To the right 4100 tower and another 4100 with jib |
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2 |
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3
No asphalt on the lifts span. It will have a concrete wearing surface |
The source of the above link was a
share by Ben Stalvey.
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Rick Webber commented on Ben's share
the machine that drilled the caissons. good oke" 4100w |
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Rick Webber commented on Ben's share |
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Nicholas Green II commented on Ben's share
I drilled with it at Sarah Long for Case Foundation. We’re using the same Cianbro 4100s2 and barge with a different attachment at the Portsmouth Naval Yard. Old school still has its place... |
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Nicholas Green II commented on Ben's share |
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Ruben Schofield commented on Ben's share |
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Ruben Schofield commented on Ben's share
Floating in the center span MLC 300 VPC max. Cianbro newest crane. Yes this is. And a 4100 ring in the back ground. Very nice crane surprised the Manitowoc 16000 wasn't on site too. 16000 was on a wind job at the beginning of this job. Now it is on a small power plant job. |
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Sarah Mildred Long Bridge Replacement Project posted
Today [2017 Oct 26] we are conducting test lifts of the Lift Span. The channel is still scheduled to be open to marine traffic tomorrow morning at 6am |
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Ben Stalvey shared
Cianbro Manitowoc MLC 300
Sarah Mildred Long Bridge Replacement Project posting
Cianbro is loading the sheave walls for the Portsmouth Towers onto one of their barges. These sheave walls make up the precipice of the towers, and are what the sheaves (shown in the bottom of this picture on their sides) will sit on |
Ron Nadeau
posted two photos.
Very nice Mlc300
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1
SML Bridge !! I am amazed that the hoist and boom are all attached to the booms. I guess I've been on friction cranes too long.. |
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2
I don't think that stand on the end of the VPC max is going to help. |
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John Pearson posted
Mlc300vpcIII |
Some shots of the last train over the old bridge. Carrying a couple of spent-nuclear-fuel cars away from the Naval Shipyard.
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Brian Hold posted, the bottom was cropped This is the Sarah Mildred Long Bridge that connects Kittery , Maine to Portsmouth New Hampshire.US Route 1 . This bridge has two decks . Road on top railroad on the bottom. The road deck is lowered when the train needs to go to the Portsmouth Naval Shipyard. ( Rails are embedded) Randy Tiell Shouldn't there be a 2nd bridge deck? Only looks like one.Brian Holt Randy Tiell the 1940 bridge had two decks on it. Because back then it was seeing multiple trains a day. It was Boston and Maine eastern route.Brian Holt Randall Hampton many issues with this bridge design, construction and now. |
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Brian commented on his post Here's the old 1940 bridge. |
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Brian commented on his post There's the original bridge. Auto and rail. It was owned by the Boston and Maine Railroad . Boston and Maine # 3666 went off this bridge when it's replacement bridge was being built. Two people died in the accident. Back in the late 30's |
Four photos from
the bridge designer, Hardesty & Hanover.
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