Soil and Precipitation Forecasts Show Possibility of More Flooding This Year
Nebraskans are still recovering from record flooding last month, but the risk of flooding isn't over. Conditions throughout the spring and summer could lead to more damage.
Several different factors led to last month's record-breaking flooding in eastern Nebraska. There was the bomb cyclone itself, which dropped a lot of snow and rain on the state. Before that storm, it had been a very snowy couple of months, so heavy rain melted significant snowpack. In other circumstances, that water could have gone into the ground, but the ground was already too wet, so there was near 100% run-off. And Ice jams topped it all off.
Some of those factors won't be a problem in the next couple months, mainly because temperatures are warming up.
Kevin Low is a Missouri Basin River Forecast Center hydrologist for the National Weather Service. He spoke last week to a packed house at an Army Corps of Engineers spring public meeting on Missouri River operations in Nebraska City.
“River ice conditions: river ice is rapidly becoming a non-player for flood risk. Still got ice on the James. I think though that for the most part it won't exacerbate river stages.”
The James River that Low mentioned runs through North and South Dakota.
The transition into spring also means there's less snowpack on the plains, though last week's blizzard did add to what was there.
Snow at higher altitudes usually melts later in the season. Low says that shouldn't be a huge problem this year.
“The one bright spot I can tell you is that the mountain snowpack, the Rocky snowpack, is near normal, and so we do not expect flooding from mountain snowmelt.”
The Rocky Mountains may seem far away, but they are part of the Missouri River Basin, which functions as a system. That also means ground conditions and precipitation across a wide area matter to how much water eventually ends up in the Missouri.
Low explained the precipitation forecast for the river basin over the next few months, and showed a map of the country with a large swath of green over the plains states.
“The likelihood, where you see green, says that the likelihood is that we will have above normal precipitation. So the bottom line there is that we are in an active pattern and it does not look to change.”
Where will that rain go? With ground conditions as they are, likely into the river system.
“The plains' soil is extremely wet. We're saturated. And so the plains will remain vulnerable to flooding into mid-summer. The eastern portion of the basin remains at what we would call an enhanced risk for flooding. I expect moderate level flooding to be episodic and to last throughout the early part of the summer anyway, into mid-summer.”
Of course, all this doesn't guarantee there will be more flooding. But what could more floods mean for Nebraska communities working to rebuild?
Gregg Goebel is director of emergency management for Otoe County, in southeast Nebraska. He's already thinking about different ways flooding could occur there.
“Otoe County directly, if the rain is actually over the county itself specifically, could experience some light flooding, nothing like what we have seen on the Missouri River. What we watch for and we're the most concerned about is what happens in the Missouri River basin to the North, up towards the northern part of the state and into the Dakotas.”
The possibility of more flooding has people on both sides of the Missouri, including in Otoe County, a little on edge.
“We got a lot of people that are concerned, especially the farmers and the residents that are in Otoe County from the Iowa side of the river, not being able to get back to their homes and their property, concerned whether they're gonna be able to get crops in the ground.”
In terms of preparing for more floods, one of the big protectors will be levees. Unfortunately, many were damaged by flooding last month.
Paul Johnson is director of the Douglas County Emergency Management Agency.
“The Platte River flooding that occurred here recently, we've had some levee and some dike repairs that have been significant. In fact they're still ongoing. So those repairs were instrumental in helping us prevent any kind of a future situation like we've had.”
John Hudson is a colonel for the Army Corps of Engineers, the agency that manages many levees along the Missouri River .At the public meeting last week he explained the corps' strategy for repairing damage to their levees.
“What we do in this first phase is to close the breeches that currently have flow through it. The second phase is to put interim measures in place. And we'll be working throughout this year to put interim measures or temporary measures in place to allow us to provide a minimum level of protection in those levee systems.”
In areas where levees did not breech, there can still be significant erosion that will need to be repaired.
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