Flooding concerns expected to continue through spring
This time of the year, western South Dakota is no stranger to flooding. The bitter cold and heavy snow this past winter is already creating headaches for those in the plains and the flooding concerns are not ending anytime soon.
2018 brought above average rainfall to western South Dakota. Rapid City finished the year with over 9″ above normal levels. Moving into February, Rapid City’s average temperature was just 8 degrees. Well, those two things set us up for some problems as winter comes to a close.
“Our ground is still frozen,” said Melissa Smith, Service Hydrologist with the National Weather Service. “We’re still looking at the ground frozen, two to three feet down and because of that, it’s not allowing the water to go into the ground right now and we’re having flooding concerns.”
Warmer temperatures are welcome after the bitterly cold winter but in regards to flooding, warmth is not the biggest help when it comes to mitigation.
In Rapid City, the snow melt goes into the storm drains. Further east, where they received much higher amounts of snow from the recent blizzard, there are more problems.
“It’s still all in piles and drifts and as it melts, it’s going into all the low-lying areas,” said Smith. “It’s ponding on the roads and we’re starting to see ice jams in the rivers as well.”
Looking ahead, Smith says that even with average precipitation this spring, much of western South Dakota is looking at an enhanced flood risk.
As the top layer thaws out, the ground will still be very saturated so any added water, will run off and amplify the flooding concern. Run off does bring some good though.
“It’s good for filling up stock ponds and dug outs and those sort of things so this kind of run off is good to help those for the summer,” said Smith.
So heading into the wettest months of the year, with the bulk of western South Dakota already above average for rainfall, paying attention to flood advisories, watches, and warnings, is key.