For only the fourth time in about three decades, the state will scatter coal ash over the Platte River with hopes of reducing the threat of ice jams and flooding.
Al Berndt, assistant director of the Nebraska Emergency Management Agency, said Tuesday that officials are worried by the unsually deep and widespread snowpack in northeast Nebraska and stubbornly thick ice on the river
A crop duster will drop about 86 tons of ash over about 10 spots along the river on Thursday, Berndt said.
The ash comes from the Nebraska Public Power District coal plant near Hallam.
The hope is that the dark ash will absorb the sun's energy and help “rot” the ice so it breaks up into smaller chunks and washes downstream, Berndt said.
Larger ice chunks can jam together like a dam and send floodwaters washing over levees.
Success is not guaranteed. But there are no other preventive steps officials can take.
An alternative, something not espoused by state or federal officials, would be to dynamite the ice. A last resort undertaken only after an ice jam occurs, dynamiting is a decision left to local authorities.
Among the sites that are a priority for dusting, Berndt said, are locations downstream of the confluence of the Platte and Elkhorn rivers.
Berndt said officials want to help make sure the Platte is open and able to accommodate water flowing into it from the Elkhorn and its tributaries. Those rivers are not being dusted because the airplane cannot safely maneuver above their sinuous channels.
The Platte is one among many rivers at risk for flooding. Officials across the Plains and Midwest are monitoring rivers and snowpack.
For now, the Platte is the only river in Nebraska and Iowa targeted for dusting, said Paul Johnston, spokesman for the U.S. Army Corps of Engineers. Federal approval is require to dust a river.
Marlin Petermann, assistant general manager of the Papio-Missouri River Natural Resources District, said ice on the Platte is averaging about 16.7 inches thick. That's in the range that can pose problems, he said.
The cost of the dusting is expected to be less than $100,000 Berndt said. Petermann, who has spent much of his 35-year career watching the river, said it's money well spent.
“Boy, anything we can do to help prevent flooding and save millions of dollars and potentially lives, it's a small investment.”