Sarah Mildred Long Bridge

Portsmouth, New Hampshire - Kittery, Maine

Project Description

The original Sarah Mildred Long Bridge, built in 1940, provided a regional link between Maine and New Hampshire, and was the critical backup route in case of disruption on the Interstate 95 bridge.

The 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 are 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 support the 300' long streamlined structural steel box girder lift span. The new bridge layout uses eleven (11) fewer piers than the original bridge.

Aspire Bridge Magazine Article: Sarah Mildred Long Bridge

Awards

American Segmental Bridge Institute (ASBI) 2019 Bridge Award of Excellence

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Our Role

Working with construction engineer, McNary Bergeron & Associates, Hatcher Technical produced construction shop drawings for the full bridge, both substructure and superstructure. This included;

Fully integrated shop drawings for the main span tower foundations.
Fully integrated shop drawings for the 4 main span lift towers (88 total segments)
Fully integrated conflict free 3D models of the cast-in-place tower caps
Fully integrated shop drawings of the cast-in-place tower caps