Structure Safety Concerns Delay Sakonnet Bridge Completion Date
Steel supports used to hold up temporary blocks to the new bridge's massive concrete piers raised safety concerns last winter.
Time taken to modify a structural and safety issue last winter on the new Sakonnet River Bridge has delayed the project’s completion by 140 days, according to the Rhode Island Department of Transportation’s (RIDOT) Deputy Chief Engineer Frank Carrao.
The $163.7 million project to replace the aging bridge broke ground in April 2009. The bridge connects Tiverton to Portsmouth and the rest of Aquidneck Island. In a phone interview last week, Carrao said the project’s contractors, Cardi Corporation, have been out there this month working expediently to get the timeline back on track so all traffic is off the existing Sakonnet Bridge by May 2012.
Workers’ safety concerns were raised late last winter after inspections revealed steel being put in place to support temporary concrete blocks, called pile caps, which may not have the reliability for support needed. These brackets are being used to reinforce support to large piers driven deep into the Sakonnet River bottom. Carrao said the work is temporary and not part of the permanent structure.
“It never compromised the integrity of the structure,” he said. “It’s to withstand the loads of all the concrete and steel needed to be placed on it.”
Carrao said DOT accepted a proposal by Cardi at the beginning of the summer to go ahead with the modifications, and since then, they have been working aggressively to complete Piers 3, 4 and 5.
“That’s the most important step so we can continue setting the steel on the Tiverton side and continue across,” he said.
Tube girders will be laid down once the piers are properly supported, which aim to support the bridge itself into place.
“Right now, nothing else can really go forward,” Carrao added, about the new Route 24 approaches on the Portsmouth and Tiverton sides.
Carrao could not provide a dollar value to the recent modifications but said they are costly.
“There’s no additional cost to the state,” he said. “They are being absorbed by the contractor.”
Carrao noted there are no major deficiencies with the current Sakonnet River Bridge, and it is being reviewed every couple of months.
“We have monitoring systems on the bridge that record any type of movement, twenty-four seven,” he said. “It remains an ongoing process until all traffic is off the bridge.”
A 2009 traffic study reveals that the bridge averages approximately 32,000 vehicles a day crossing it, Carrao noted.
A separate contract will go out to bid for demolition of the existing bridge once the new one is completed, he added. Hopes are that the contract will begin in the spring of 2013. Carrao said concerns have been raised about the close proximity of the new and old bridge and the high tension wires that cross the river.
Charles St. Martin III, DOT spokesman, said it will take one year and 18 months to complete the demolition and any further delays will affect that timeline.
Carrao reiterated that the Tiverton highway approach for Route 24 north is complete, as well as its bridge deck work and reinforements, but nothing else can commence until the piers are finished. He said Cardi will start on the Tiverton side and work their way to Portsmouth.
“You will see quite a bit of activity there over the next several months and through the winter, I imagine,” he said.