AASHTO Journal, 26 August 2016
Officials of the New Hampshire Department of Transportation and Maine Department of Transportation said Aug. 24 they had to permanently close the malfunctioning Sarah Mildred Long Bridge to motor vehicle traffic more than two months early.
The 76-year-old lift bridge connects Portsmouth, N.H., and Kittery, Maine, on the US 1 Bypass over the Piscataqua River. It suffered a mechanical failure on Aug. 21, the DOTs said. Early the next day engineers were able to lift it to the “up” position, which allowed boats to move beneath it but forced motor vehicles to detour to another crossing.
“By keeping the bridge in this position, federal law, which requires a bridge to be accessible to marine traffic at all times, is adhered to,” the state agencies said.
Soon, however, NHDOT and Maine DOT engineers along with movable bridge experts determined the bridge was not safe for routine operation without extensive repairs that were estimated to cost at least $1 million and take six weeks.
But a project under way to replace the structure meant the Sarah Mildred Long Bridge was already scheduled to close permanently on Nov. 1, so that construction could allow the new bridge to open in September 2017.
“Careful consideration has been given to the negative impact to motorists and the communities, versus the cost, time and uncertainty involved in any repair of this magnitude,” the two agencies said in announcing their decision to keep the bridge open to marine traffic but close to roadway vehicles.
They said detours are in place for motorists to use alternative routes between Portsmouth and Kittery by the Interstate 95 “High Level” Bridge and the Memorial Bridge on US 1.
