State highway officials have decided to remove all of the panels from the walls of the Callahan Tunnel in the coming days, instead of waiting until next year as originally planned.
The new approach was disclosed Wednesday by Frank DePaola, highway administrator for the state Department of Transportation, at the department’s board meeting.
Last month, one panel fell into the roadway, tying up traffic for several hours. Three other panels were immediately removed. Workers have since taken out roughly three-quarters of them, said Transportation Department spokeswoman Sara Lavoie.
DePaola said at the meeting that the initial plan to conduct regular tests on the panels before scheduled renovations to the tunnel next year, when they would need to be removed anyway, was too labor-intensive.
He said the department will solicit bids for the broader renovations, which are slated to take place between January and April of 2014.
“The tunnel will remain without these architectural panels until such time as the rehab contract has gone into effect,” DePaola said Wednesday. “That way everybody is assured that there’s no danger of an old panel inadvertently falling and causing a safety concern.”
Lavoie said the panels in the tunnel serve no structural purpose, but were installed to cover the concrete wall and add brightness with their reflective coating. They are also easier to wash.
“We are asking drivers to be sure to have their headlights on,” but the tunnel will not be pitch black without the panels, she said.
DePaola said on Thursday that about 1,800 panels had been removed, and the work is being conducted between 11 p.m. and 5 or 6 a.m., so the main commuting hours will not be affected.
He said at the meeting that all panels should be gone in a week or two.
State Representative Aaron Michlewitz, a Boston Democrat who has filed a bill dealing with insurance coverage for highway tunnels, expressed support for the expedited removal of the Callahan panels.
“I’d rather MassDOT and the Commonwealth do something that is better safe than sorry,” Michlewitz said.
DePaola said by phone that the major Callahan repairs will happen next winter because the ongoing renovations to the Tobin Bridge will be on hold at that time.
“I don’t want to have too many lanes taken out of service” at once, DePaola said.
Lavoie said painting and preservation work on the Tobin began last spring and lasted through the fall, and will continue during the same time frame this year and in 2014.
The overall Callahan project will cost an estimated $12 million, and the Tobin job is budgeted at $45 million, according to Lavoie.
Like the Callahan, the Tobin’s infrastructure has recently shown its age.
In July, a 10- to 15-pound light fixture fell from the bridge onto the roadway. No one was injured, and DePaola said at the time that the likely cause was corrosion in the two-decade old fixture’s support bracket. Workers later removed several additional light fixtures from the bridge.
And in December, workers removed 26 loose wall panels inside the Sumner Tunnel during an inspection. DePaola said at Wednesday’s board meeting that the Sumner panels will be reinstalled with a repaired fastening system.
The close look at the Sumner followed an inspection of the Callahan, performed after its wall panel fell, that found 121 loose panels in that tunnel.
Annual inspections of all tunnels were prompted by a 2006 ceiling-tile collapse in the connector that links the Ted Williams Tunnel with other sections of the Big Dig, killing grandmother Milena Del Valle.
Michlewitz said of officials’ various renovation plans, “I think it does reaffirm some of the issues we’ve faced in terms of transportation structure and infrastructure. They are obviously on the front-burner of many peoples’ discussions” going forward.