SPENCER, Iowa — Heavy rains and extensive flooding in northwest Iowa are causing untreated livestock waste from animal feeding operations to enter the area’s rivers and streams, according to the Iowa Department of Natural Resources (DNR).
Lois Benson, environmental specialist at DNR’s Spencer field office, said 26 livestock operations reported their manure storage systems were overflowing.
“They are reporting they’ve received from 7 to 12 inches of rainfall, with more expected tonight,” Benson said. “The vast majority have a national pollutant discharge elimination system (NPDES) permit. In essence, this permit allows them to overflow in heavy rains.”
She said most of the discharging livestock facilities are in Lyon, Sioux, O’Brien and Clay counties.
“We’re telling them to hold the overflow as best they can and try to prevent it from reaching a stream,” Benson said. “Some are transferring it to other areas. Some are trying to contain it behind terraces.”
She said about 18 communities between Alton and Sioux Center have reported discharges from their wastewater treatment plants due to the intense rains.
While fast stream currents are the biggest risk for people, high waters can also carry debris and bacteria.
“The safest course is to stay out of the waters until several days after streams return to normal depths,” Benson said.
Livestock producers who expect to discharge untreated animal waste into rivers and streams need to call the Spencer DNR field office at 712-262-4177.
