NORTH ANDOVER — With another winter storm bearing down on the Merrimack Valley, local school districts are taking no chances with their roofs.
Yesterday, the Greater Lawrence Regional Technical School was shut for the third day in a row as contractors using cranes and shovels cleared 8-foot drifts. Superintendent John Lavoie said he feared that the heavy, wet snow or rain expected for today could add even more weight to the roof and cause a cave-in.
In Methuen, school officials will close the city's five schools on Monday and Tuesday and hire contractors to clear snow from school roofs.
"The schools are absolutely structurally safe but there are drifts as high as ten feet and we need to remove the snow as soon as possible," Judith Scannell, interim superintendent, said in a statement.
Scannell, Methuen Mayor William Manzi, Methuen Public Works Director Ray DiFiore, and Methuen Director of Facilities Bruce Stella agreed unanimously on the decision. Several companies will come in with cranes and shoveling crews to start clearing the drifts off all school building roofs.
Manzi said the city has also hired a structural engineer, scheduled to start work immediately, to determine the problem areas that snow-removal contractors should focus on.
"This has to be done," Methuen Mayor William Manzi said. "There's no way around it and no consideration of cost."
He said the crews would work through the weekend, including during today's storm.
"With all that snow on there, the only prudent thing to do is get rid of it," he said, adding that if the work crews are unable to make adequate headway in removing the snow, "we may have to hire more contractors."
In Georgetown, all schools were shut yesterday pending an inspection of all facilities after a section of the Perley Elementary School's annex collapsed.
In Andover, the school department published a statement on its Web site that all buildings are being inspected internally and externally and snow is being removed from problem areas.
In North Andover, the superintendent assured parents in an e-mail that all school roofs have been inspected or are being cleared of excess snow.
At Whittier Regional Vocational Technical High School in Haverhill, Superintendent William DeRosa hired a roofing company a few weeks ago to remove snow, mainly from the roof of the gymnasium.
"Our roof is new and we wanted to make sure it was a bonded company that did the snow removal," he said.
Workers with shovels toss snow off the edge of the roof onto the ground beside the gym, then Whittier's maintenance crew use a front-end loader to haul it away and dump it in the school's south parking lot.
"I've done it before every storm starting two weeks ago after we noticed a slight deflection in a ceiling I-beam in the gymnasium," DeRosa said. "We had called in a structural engineer to look at it, and they certified it was safe. But at that point we contacted a roofing company to have the snow removed."
They've returned several times, and will be here again today, he said.
DeRosa said he focused on removing snow from the gymnasium's roof as it does not have the same type of concrete decking material as roofs in other sections of the school have.
It's a similar problem at Greater Lawrence Technical School in Andover.
Superintendent Lavoie said the school was originally built in the early 1960s, when designers and builders didn't take snow drifts into account when determining snow-loads. The newer parts of the building were constructed with additional snow loads in mind, he said, but the drifts appear to have collected on top of the original building.
"Just seeing 6- to 7-foot snow drifts on the older portion of the building, I knew, when we looked up there, we had some concerns, and might have some issues," he said.
Lavoie said he spoke with inspectors from the state and the town of Andover, and consulted structural engineers, who advised him to shut the school until the drifts could be removed.
"We have 8 different areas with huge drifts, so those are the areas we are clearing," he said. "We have two more areas of concern to clear, then we'll be safe to reopen on Monday."
Yesterday, two cranes worked all day lifting tarpaulin baskets, filled with up to 1,800 pounds of snow each, from the roof and depositing it into piles below. The snow is being hauled away from the building with backhoes and dump trucks and piled up on the practice football field behind the school.
Lavoie said that working with a structural engineer, the school made some calculations to determine how much the snow weighed and where it should be taken from. Because it was mostly lighter snow, it was putting about 28 pounds per square foot of pressure on roofs that can withstand about 45 pounds per square foot.
With the rain or heavy, wet snow expected, that weight limit could be reached, he said, which could result in roof collapses.
It's a concern not just for muncipal buildings.
In Andover, several homeowners have called to report cracked ceilings or warped windows indicating potential roof problems, according to Building Inspector Kaija Gilmore.
"I was with the Fire Department this morning looking at roofs that showed cracking and will probably cave in," she said. "One older home with a screened-in porch doesn't have the structural integrity. The windows are already buckling out. But the main part of the house is OK."
Fire Chief Mike Mansfield said the house, located at 8 Downing St., has 3 to 4 feet of snow on the porch roof. Next door, at 10 Downing St., the homeowner called to report cracks in the ceiling and walls of the house, he said.
Gilmore said the homeowner was "very upset" about the cracks and was advised to hire a roofing company or contractor to remove the snow immediately.
Mansfield said there is a major commercial building in town, which he refused to identify, also experiencing problems. He said the company has hired a company to remove the snow, which seems to have solved the problem.
"The issue is going to be compounded with additional snow forecast for Saturday and next week," he said. "There is 3 to 5 feet of snow on residential roofs, and they are not designed to carry that kind of snow load. Some snow on roofs can weigh up to 35 pounds a cubic foot."
He said he can't remember a winter like this in 30 years.
"This is an extraordinary winter we are experiencing," he said. "I can't remember this kind of snow in at least three decades."
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