Iowa DNR continues investigation into Montgomery County fertilizer spill that led to fish kill in East Nishnabotna River

Red Oak, Iowa — The Iowa DNR issued a press release earlier this week, saying that on March 11, New Cooperative in Red Oak, Iowa, notified the DNR of a release on-site early Monday morning.

Approximately 1,500 tons of liquid nitrogen fertilizer (32% solution) discharged into a drainage ditch, then into the East Nishnabotna River. The release occurred due to a valve left open on an aboveground storage tank overnight. 

Areas of pooled fertilizer were pumped into a vac truck and will be land applied later. 

Dead fish were observed in the East Nishnabotna, and the extent of the fish kill was still being determined. Samples were collected and will be analyzed. 

In an update on March 13, the Iowa DNR said staff continue to investigate the New Cooperative fertilizer spill, with clean-up efforts still underway.

The product flowed several miles downstream of Red Oak in the East Nishnabotna River, reaching Missouri. The Missouri Department of Natural Resources has been notified.

Test your wells

The Iowa DNR encourages private well owners in Montgomery, Page, and Fremont counties with wells in near proximity to the East Nishnabotna River to contact their county health department to test their wells for nitrate. 

This service is free using Iowa’s Grants-to-Counties (GTC) program. The DNR will be providing county health officials with lists of registered private wells that may be vulnerable.

Due to low water levels in the East Nishnabotna, the concentration of the liquid nitrogen fertilizer is higher than during normal stream flows, causing concern for all animals due to high nitrate and urea levels.

Iowa State University College of Veterinary Medicine Toxicologist Scott Radke recommends keeping all animals away from the East Nishnabotna River until the plume of contaminant moves out of the area. 

The Iowa DNR is working with local, state and federal officials, and will continue to investigate impacts of the spill.