Major work urged for Williams Tunnel
Firm sees need for adding 900 ceiling anchors
The to-do list on the $14.8 billion Big Dig grew again yesterday, as an engineering firm hired to inspect flaws following the July 2006 fatal ceiling collapse recommended installing about 900 support anchors in the Ted Williams Tunnel.
The anchors would add support to two sections of the tunnel's ceiling - each about 250 feet long - that are impossible to inspect because they were designed without a crawl space. The new supports would fortify epoxy bolts, similar to the type blamed for the fatal ceiling collapse in the Interstate 90 connector tunnel that killed 38-year-old Milena Del Valle of Jamaica Plain.
"We think this is a viable alternative, cost-wise," said Gary Klein, an engineering consultant with Wiss, Janney, Elstner Associates, hired to review all of the authority's roads, tunnels, and bridges.
The ceiling has redundant support built in and does not pose an immediate safety threat, Klein said, but it should be addressed within five years.
The ceiling could also be removed and inspected, but it would probably cost more than adding the 900 support anchors, Klein told the Turnpike Authority yesterday during its monthly meeting. He did not provide precise cost estimates for either solution, but said it was likely to cost millions.
To make the repairs, the authority may be able to use money generated from January's $458 million settlement with the project's contractors, led by Bechtel/Parsons Brinckerhoff.
Turnpike Authority engineers have not responded to the recommendation. Klein's contract expires at the end of June, when he and others are scheduled to make a final report to Governor Deval Patrick.
Klein also recommended retrofitting an additional 180 anchors in the Ted Williams Tunnel that are bolted into unsettled or cracked concrete or where the concrete may be showing signs of leaking or slipping.
He also recommended adding a fire-safety system that would flush the Sumner and Callahan tunnels with water in the event of a fire.
Klein said the ventilation system in those tunnels - opened in the 1930s and 1960s - is weaker than others and that any failure could compromise safety in the event of a fire.
Noah Bierman can be reached at nbierman@globe.com.
