SIOUX CENTER (AP) — The Iowa Natural Resources Department is investigating a fish kill in northwest Iowa.
The agency is checking the West Branch of the Floyd River, about 2½ miles south of Sioux Center.
Department workers found elevated ammonia levels in the water and several dead fish north of the U.S. Highway 75 bridge crossing.
The department says high ammonia content usually means the source is a nutrient, often fertilizer, manure or wastewater.