GRAFTON, Ill. — Last year saw near-record crests along the Mississippi River.
J.D. Lorton and his family may have the best view of the Mississippi River from Aerie’s Resort, one that draws people to Grafton to view the mighty Mississippi. For nearly three months last year, water covered parts of the Great River Road that runs through town.
Lorton said when people can’t get there, it affects all the livelihoods of the people in Grafton, especially the business owners and residents.
Growing up along the river, Lorton said, “you’ve always had some spring floods, but nothing like the major floods we’ve had here, especially the last five years."
Last year was one of the wettest on record. Corey Loveland is the service coordination hydrologist at the North Central River Forecast Center near Minneapolis. He said in a period of 125 years, 2019 was the wettest in many places.
“Last year we came out with the spring flood outlook and everything was high, we expect those to be high as well for this year,” Loveland said.
Loveland said the wet pattern has continued through the fall and into January. With already saturated soil that is now covered with a deep snowpack in many places, there is already concern about the flooding potential again this year.
For hydrologists to be able to make good forecasts, they need to know how much water is in the snow. That requires specialized surveillance from low flying National Oceanic and Atmospheric Administration aircraft. Carrie Olheiser is the operations lead down the hall from the hydrologists in the Hydrologic Remote Sensing Center. She says NOAA planes fly at about 500 feet above the ground collecting gamma radiation readings. Those readings allow their team to estimate just how much water is in the show if it was melted. That information is used by the hydrologists as they forecast the rise and fall of the river.
Olheiser said the planes fly predetermined routes all over the country to find the snow water equivalent in the snowpack.
Back down the hall, Loveland notes that the wet saturated soil, snowpack and frozen soil all play a role in the spring flooding.
The big question as to how bad any flooding along the river gets really comes down to the spring rain.
“That’s kind of a question mark,” Loveland said. “Because we don’t know what it’s going to do in the springtime. If you have really warm temperatures and additional rainfall in the spring, that accelerates snowmelt.”
That combination can create a significant jump in river levels.
The Climate Prediction Center is forecasting above-average precipitation over most of the Missouri and Mississippi River basins for March, April and May. With the Mississippi River already a bit higher than average, the odds of flooding would seem to be higher again this spring.
“We know we are going to have high flows, we just don’t know how high or how long they will be," Loveland noted.
The Mississippi River basin drains about 40% of the U.S. including the Missouri River basin. River flows have been higher than average on both rivers through the winter. With the extensive snowpack in the Rockies that will drain into the Missouri River, the Army Corps of Engineers is already releasing water from reservoirs along the Missouri River.
The official spring flood outlook from the National Weather Service will be issued in the next couple of weeks. Back in Grafton, Lorton said he knows the river will go up again but he also knows the people in this region are very resilient.
“We did come back. It was a great effort by the mayor, the city, business owners and residents…to get Grafton back on the map.”
After all, with perhaps the best view in the Midwest, “tourism is our industry.”