BRATTLEBORO — For more than two years, Interstate 91 traffic has bottlenecked at the site of a $60 million bridge-replacement project.
But officials say there is light at the end of the construction zone: A new, 1,036-foot-long bridge is expected to be ready for four lanes of traffic sometime later this year.
Given that the traffic flow originally was supposed to be restored in late 2015, “we're not where we want to be with the schedule,” acknowledged David Hoyne, the state Agency of Transportation (VTrans)'s director of construction and materials.
But Hoyne otherwise had nothing but praise for lead contractor PCL's handling of the complex bridge job.
“At the end of the day, what we have to have is a quality bridge that's going to last a very, very long time,” Hoyne said. “From that perspective, they have been very good.”
Two green steel bridges previously had carried I-91 across Route 30 and the West River. But those spans, which were more than 50 years old, were considered structurally deficient and too narrow by current safety standards.
In fall 2013, PCL diverted all I-91 traffic onto the steel span that previously had carried two lanes of southbound traffic. Since then, the northbound steel bridge has been demolished and a new, arching concrete bridge is taking shape in its place.
The new bridge will carry all four lanes of traffic and has been hailed as a marvel, in part for the construction methods being carried out by PCL. Administrators say “balanced cantilever construction” will allow crews to advance across the gap with minimal impact on Route 30, the West River, and the West River Trail below.
The bridge's design also is unique. In response to initial complaints about a fairly plain-looking bridge that had been planned at the site, state officials worked with a local committee to come up with design criteria and evaluate bidders for the project in 2012.
Pennsylvania-based FIGG Bridge Engineers eventually came up with a design that's been billed as “A Bridge to Nature.” It includes curving, “cathedral” piers that feature viewing platforms overlooking the river; also, Hoyne noted that the rounded bottom of the bridge “will be colored blue to look like the sky” for boaters and pedestrians underneath.
The project's aesthetics “are going to be remarkable,” Hoyne said. “When this thing is done, people should be in awe over its beauty.”
Hoyne also remarked on the engineering that went into that design. He said it is “enormously complex” to form and reinforce the curved columns, and he noted a “massive amount of steel” in the tables atop those piers. That latter design element alone extended the project several months past its original time frame, Hoyne said.
Other factors, including permitting delays, unexpected digging difficulties, and harsh winter weather contributed to the project's delays, officials have said. In March 2015, VTrans announced that the new bridge was about a year behind schedule.
Since then, though, the project seems to have stayed on track.
“We are targeting completion of the new bridge by the end of 2016,” PCL administrators said in a prepared statement. “There is (additional) work that will be completed in 2017, including demolition of the existing bridge currently carrying traffic and completion of the roadway tie-ins.”
Hoyne said VTrans has been keeping close tabs on the project, with a resident engineer staying in daily contact with PCL. He agreed with the contractor's assessment of the project's remaining schedule, though he could not say exactly when the new bridge will be able to bear traffic.
“Our goal is to get this job to four lanes of traffic before next winter sets in,” Hoyne said. “Whether that's in November or December .... on a job this big, the schedule moves around a little bit.”
“Anything can happen,” he added. “I'd like to think we're not going to have the horrific temperatures we had last winter, but we don't know.”
PCL and its subcontractors continue to work through the winter. The company said crews are constructing bridge sections atop Pier 1 on the Route 30 side of the project, and that half of the bridge is scheduled for completion in the spring. Bridge sections on the opposite side will follow.
The project also includes replacement of a smaller bridge nearby that carries the interstate over Upper Dummerston Road. PCL said the foundations of that new bridge are complete, and the beams and deck will be erected this summer.
There have been periodic traffic disruptions associated with the I-91 bridge work. Though complete closures of Route 30 have been infrequent, the road is sometimes reduced to one lane as crews work on the bridge above.
Traffic flow on I-91 has been a much bigger concern. The state's solution has been to close the on-ramp at Exit 3 when heavy southbound traffic is expected - for instance, at the end of a holiday weekend - in order to ease pressures at the merging point for the construction zone.
Such ramp closures “definitely will continue,” Hoyne said. “And the reason it will continue is that the numbers tell a story. What the numbers tell us is, without closing that ramp on peak travel weekends and at peak times, the southbound interstate turns into a parking lot.”
Hoyne said VTrans strives to close the ramp only when necessary. Officials study the interstate via data gathered by message boards near the construction zone: In addition to conveying construction alerts, those boards are monitoring the speed and volume of traffic.
Hoyne said VTrans also has been working closely with Brattleboro officials, because the downtown area takes the brunt of traffic that's been diverted from I-91. Town Manager Peter Elwell said the state has been a “good partner” throughout the project, accommodating the town's requests when possible.
“After we suffered gridlock during the first couple of closure weekends, they started actively monitoring those impacts and have reopened the interstate early on certain weekends since then,” Elwell said.
“Bottom line - the traffic impacts in Brattleboro have been significant and difficult for both residents and merchants,” Elwell added. “But we appreciate the way VTrans officials and PCL have respected and responded to the town's concerns.”