Rocks Village Drawbridge
East Haverhill to West Newbury, Massachusetts
Constructed in 1914, the Rocks Village Drawbridge spans the Merrimack River and serves as a vital connection between the historic Rocks Village section of East Haverhill, Massachusetts and neighboring West Newbury across the river. When operational, the drawbridge shortens commuting time by approximately 45 minutes for hundreds of motorists traveling between the towns every day, and additionally provides a key access point for boat traffic through the navigational channel.
The bridge’s truss on the swing span was heavily damaged when struck by an over-height tractor trailer. MassDOT found that the portion of the bridge where the crash occurred sustained “significant damage to several key structural components” and was forced to close for repairs.
Salisbury, Mass.-based prime bridge contractor SPS New England was awarded the MassDOT emergency drawbridge reconstruction contract. Gill Engineering of Needham, Mass. assessed the portions of the steel truss that would be removed, led the design phase for the structural repairs and oversaw the horizontal and vertical positioning of the swing span in preparation for partial demolition and replacement.
Meridian Associates, subcontracted by SPS New England, performed differential leveling at every phase of the operation on select locations on the truss. The baseline elevation data on said points prior to the swing span opening became the design position to maintain during the entire repair. In the open position, the swing span required jacking towers on historic wooden fenders to hold its weight and structural integrity.
SPS faced multiple challenges throughout, such as the impact of the river’s tidal force on the structural elements, the historic wooden construction of the fender piers on which the entire repair operation depended, and periods of extreme summer heat that caused significant expansion of steel, impacting elevation data. Adjustments to the vertical positions of the bottom chord of the swing span were in the order of 1/8 of an inch.
Meridian Associates, Inc. was a proud partner with SPS New England on this project.