Drought persists under Minnesota snow, but is that all bad?

If Minnesota's now-deep snowcover melts and runs off over frozen ground, it will do little to ease the worst drought in decades. But there will be some beneficiaries: ducks, among others.

Runoff that heads into low spots in the landscape, including wetlands that were nearly dry last fall, will form temporary ice-lined ponds that ducks and other waterfowl returning to spring nesting grounds will find irresistible, said Ken Varland, the Department of Natural Resources' regional wildlife manager for southwestern Minnesota.

"From our perspective, that's a good thing for migrating waterfowl," he said.

Because winter snows arrived late across much of Minnesota, drought-dry soils got so cold first that they may freeze the first meltwater that penetrates them, preventing the rest from soaking in. Across southern Minnesota, soils are capped by an even more water-resistant layer of ice that formed when December rains froze.

The current snow cover holds 4 inches of water across much of Minnesota, atop soils that are as dry as they've ever been at depths where plants will need moisture, said state climatologist Greg Spoden. It's a situation he hasn't seen since the drought years of 1987-88.

But that doesn't mean the snow and the water in it will be wasted.

For now, the deep snow should prolong the cold weather — a good thing in the eyes of Chris Ransom, secretary of the Minnesota Maple Syrup Producers' Association. A warm snap can shut off the run of sap that gets boiled down into syrup.

Also, snow on top of lake ice is limiting the light that gives curly-leaf pondweed, an invasive aquatic plant that grows under ice in the winter, an advantage over native species, said Telly Mamayek, spokeswoman for the Minnehaha Creek Watershed District.

Another benefit: When snow gives way to meltwater, moisture that doesn't get held in the soil will help replenish lakes and streams that were unusually low going into winter. Lake Minnetonka, for example, is a foot below the level at which it would discharge water into Minnehaha Creek.

Nevertheless, most landscape-watchers say a rapid melt and runoff will be the least desirable outcome this spring, providing no relief for drought, and even leading to spring flooding. The National Weather Service is expected to update its regional spring flooding outlooks Thursday.

Jason Moeckel, a supervisor in the DNR's Ecological and Water Resources division, said the next hope would be plentiful but digestible rains after the snow's gone.

"My grandfather always called them good soakers," Moeckel said. "They cover a large area, come down slowly and sink in. It's probably going to take several of those."

But there's also a belief that drought can be a good thing. Varland said some marsh plants such as cattails germinate better in dried-out soil than in a flooded wetland. And the drying of a lake bottom packs sediments, making them denser and allowing lakes to be deeper when they refill, he said.

"It's like when a forest fire goes through," he said. "Later when you get new growth, it attracts wildlife. But nobody wants to hear about dry conditions when people are looking for water."

Bill McAuliffe • 612-673-7646