State Officials in Iowa are investigating a fish kill in O’Brien County.
The Iowa Department of Natural Resources said that the fish kill was reported late Saturday at the North Fork of the Floyd River about seven miles northeast of Sheldon.
DNR staff found dead fish on Sunday starting near the intersection of the North Fork and the Floyd River and ending about four miles downstream in the Floyd River.
While they have not identified the pollutant source yet, field tests at downstream from the fork on Monday showed the water was low in oxygen and high in ammonia.
Meanwhile, investigators found the water at the intersection with high levels of dissolved oxygen and low ammonia levels, likely diluted due to rain over the weekend.
They expect laboratory results next week as they continue to investigate the source of the pollutant.