This winter, Minnesota snowplow drivers have been busy.

They've been trimming trees, filling potholes and removing buckthorn. They've been remodeling park buildings, fixing retaining walls and repairing equipment. They've been getting around to everything they'd normally have to put off — if this were a normal winter.

"I always tell people, this city is never cleaner than when it doesn't snow," said Mike Kennedy of Minneapolis Public Works.

Even as their crews are occupied with warm-weather tasks, local governments are expecting to save hundreds of thousands of dollars of public works money as 2015 comes to a close.

If the weather holds, Minneapolis could save about $1 million. Edina is looking at an extra $400,000 compared with last year. Even Up North, where snow is already blanketing the ground, Bemidji likely will save about half of what it set aside for fuel and public works overtime.

Because the money for snow removal is usually part of a government's general fund, money left over at the end of a mild winter goes back into that pool and can feed a variety of departments.

Many local government crews have been keeping busy with non-snow tasks while winter equipment has been idle. Here, Dale Cannon inspected heavy equipment in Minneapolis’ fleet.

About 6½ inches of snow fell on the Twin Cities area in November and the bulk of December — more than a foot less than the 30-year normal for those two months, according to the Minnesota Department of Natural Resources (DNR). And when more snow arrives later in the winter, the warm weather expected this season likely will melt it fast, said DNR climatologist Peter Boulay.

Still, he said, this wouldn't be the first time a winter started out slow and gained traction later on.

"If — it's a big if — if we get cold air enough in here, we could have a big snow event," he said. "I hate to say it, but there's no way to predict."

Snow is expected to fall in the Twin Cities and other parts of Minnesota after midnight on Christmas Day and into Saturday. From 3 to 6 inches are possible. A respectable amount – but not a major snowfall.

To figure out what they might spend on snow and ice removal in a given year, cities and counties rely on historical data. Burnsville looks at spending over the past five winters and throws out extremes to find a middle ground, said Steve Albrecht, the city's public works director. In Washington County, where crews maintain 275 miles of county roads, the budget is based on a three-year rolling average to account for highs and lows, said county engineer Wayne Sandberg.

County work crews do some winter maintenance even when it isn't snowing, Sandberg said — putting down salt on an icy morning, for example. Even so, crews have gone out only five times since Nov. 1, he said, compared with more than a dozen times in a typical early winter.

"It is cyclical," Sandberg said.

That up-and-down cycle means that cost savings in a mild winter will likely make up for overspending in a tougher winter. But there are still some winters that governments can't plan for.

Many public works departments spent more than expected in 2013-2014, when nearly 70 inches of snow hit the Twin Cities area. Burnsville "went way over budget" that year and used up all of its road salt reserves, Albrecht said.

The 2010-2011 winter was even more severe — nearly 90 inches of snow over the course of the season, more than a third of which fell in December. Kennedy, of Minneapolis, said a 17-inch blizzard that year "pretty much choked us." That was the storm that collapsed the roof of the Metrodome.

"You could plan for that, and have all that equipment, but then all those other years that equipment is sitting idle," he said. "So you try to do the best you can to be able to handle most situations."

Emma Nelson • 952-746-3287