The Detroit Lakes area got hit with 13 to 16 inches of heavy, wet snow over the weekend, on top of 54 inches of snow through February, according to the National Weather Service in Grand Forks - leaving local homeowners and business managers wondering if they need to clear the snow off the roof.
The question was sharpened by partial roof collapses at a half-dozen businesses and a church in Fargo-Moorhead and Perham.
And the roof of at least one home in Detroit Lakes partially collapsed from the heavy snow, along with a lean-to structure attached to a gym in the Frazee-Vergas Elementary School, among other structures, such as sheds and garages, said Jim Matter, of Farmers Insurance, James Matter Agency in Detroit Lakes.
"What we suggest, when the snow load becomes too much - about 15 inches on the roof - we suggest a roof rake or something to hopefully get about a third of the weight off," he said. Make sure to leave about three inches of snow on the roof to avoid damaging the shingles, he said.
Removing most of the snow around the edge of the roof also helps prevent ice dams, which taken in total do a lot more damage each winter than collapsed roofs, he said.
Depending on how they were built, older structures, like homes built in the 1960, 1970s and 1980s, can sometimes be more vulnerable to snow loads, said Josh Lessman, owner of Ledgestone, Inc., a construction contractor in Detroit Lakes. "They used to hand-frame the roofs, now we use engineered trusses," generally capable of bearing 40-50 pounds per square foot, he said.
Flat roofs can be especially vulnerable to heavy snow loads. "Flat roofs are tough," Lessman said.
And snow removal from flat roofs tends to be difficult, Matter said.
"With a flat roof, it's many, many hours - it's people up there shoveling it off," he said.
As if there wasn't enough snow already, another storm is on its way, with a mix of rain and snow expected Wednesday and Thursday and winds gusting up to 60 mph on Thursday, said Nick Carletta, a meteorologist with the National Weather Service in Grand Forks.
"We're keeping our eye on it, trying to figure it out," he said Tuesday. "There's high uncertainty because the rain-snow line is right over the area." Colder than expected temperatures mean the rain would become snow, and there could be lots of it. The other side of the rain-snow line has snow amounts forecast at 6 to 12 inches.
With such high winds forecast, Carletta said, "fresh fallen snow will make things challenging for travel conditions."
The Detroit Lakes area is now hovering around the 70-inch mark for snow totals this winter, he said. The record snowfall in Detroit Lakes is 90 inches for the season, set in 1943.
The Detroit Lakes Public Works Department has managed to stay on budget so far, but there likely won't be $100,000 left over for the general fund like in some low-snow years, said Director Brad Green.
The snow dump in northern Detroit Lakes is used by city, county and state plow trucks, and it's filling up fast, he said. "Everyone is running into that this year - where do we put it?" The snow dump at the fairgrounds is also filling up fast, he said. "We have some other areas we can open up if we have to," but they aren't as conveniently located, he said.
The 20-person Public Works Department is now focusing on knocking down snow piled at street intersections, and cleaning up those parts of streets that plows couldn't get the first time because of parked cars. "Please move your car off the road for snow events," Green said.
Crews are also chipping away at standing snow piles. "We're just trying to haul those mountains of snow out," he said.
Rain is forecast, but with so much snow on the street "we can't get to the catch basins," to make sure they're clear, Green said. If flooding becomes a problem, the street department will do what it can to clear catch basins, he said.
As for the coming storm, "we pay very close attention to the weather," he said. "We have our salt and sand trucks ready."
Frazee roof collapse
The partial roof collapse of a lean-to structure attached to a gym at the Frazee Elementary School has not affected operations at the school, said Frazee-Vergas Superintendent Terry Karger.
No one was injured in the incident, which occurred after the heavy snowfall over the weekend. The area received up to 16 inches of heavy snow in some places, according to the National Weather Service in Grand Forks.
The lean-to was added onto the gymnasium on the north side of the elementary school in 1987. It was brought in by the Army Corps of Engineers, Karger said. One side of the lean-to was used for physical education storage and the other side held a locker room that was not in use.
Hammers Construction of Perham is assessing the damage, Karger said.
The roof collapse "is not a good thing, but we can still move forward and have school," he said.
The damage will have no impact on improvement plans for the elementary school that were approved by voters in a referendum in November.
Under those plans, the 1966 wing on the elementary school will be remodeled and upgraded with new windows, flooring and other improvements, and the heating, cooling and ventilation system for the whole building will get an upgrade.