Deep snow pack raising flood fears

The numbers along Iowa's rivers add up to an ominous spring flooding outlook.

“There are some similar circumstances going on (compared to 2008),” State Climatologist Harry Hillaker said this week. “It's wet from the previous year, lots of moisture stored in the snowpack, lots of moisture stored in the soil. This year probably has more snowpack moisture than 2008 and ‘93 did.”

Take Mason City, where runoff drains into the Shell Rock River, which flows into the Cedar River just above Cedar Falls. Through Monday, Mason City had received 43.2 inches of snow this winter, 57 percent more than then winter of 2007-'08. Nearly three times as much snow remained on the ground Monday compared to Feb. 15, 2008.

Belle Plaine, in the Iowa River watershed, has received 37 inches of snow this winter, two more than 2007-'08. Ten inches remained on the ground Monday, compared to 8 in 2008.

“The way this winter has been, almost all the precipitation that has fallen is still on the ground,” said Hillaker. “The one thing we had going for us two years ago was, we had some pretty mild days mixed into the winter that got rid of some of that snow cover.”

Still, it's far too early to predict a flood near the scale of the June 2008 inundation, which was fed by heavy, continuous spring rain.

“The two weeks before the big crest was incredibly wet over a large area,” Hillaker said.

Given a gradual warm-up and a relatively dry spring, Eastern Iowa's rivers could remain in, or at least close to, their banks.