Fertilizer Spill into Tributary of the Maumee River in Northwest Ohio Kills Estimated 20,000 Fish

 

      In early July it was observed that parts of the Maumee River in Henry County, Ohio were turning a reddish color.  The Ohio Department of Natural Resources put out a statement on July 13 that 11 miles of the river were affected, with an estimated 18,000 to 20,000 fish killed. The fish range from 3-inch sunfish to carp over three feet long. It was found that a spill of liquid fertilizer was the cause.  28% Urea Ammonium Nitrate (UAN) liquid fertilizer spilled into Huston Creek and then flowed into the Maumee River.

     Tests of the river water for ammonia in the town of Napolean showed that it was at a level still safe for humans. However, as a precaution the town is not drawing water from the river temporarily.

“The Ohio Environmental Protection Agency issued violations to Triway Nitrogen and Farmers Elevator Associates for the fertilizer spill and required the businesses to assist with cleanup actions and take steps to prevent future contamination, WTVG reported. Both are located near the Huston Creek, which flows into the Maumee River.”

     The fish were killed by oxygen depletion when ammonia from the fertilizer reacted in the water, consuming dissolved oxygen and basically suffocating the fish.

     The highest amounts of ammonia recorded in the Maumee River were 2.8 ppm, far below the 50 ppm considered the threshold for human harm.

     Ohio EPA is leading the cleanup efforts. Heavy rainfall has helped to dilute the spill and reduce further threats to aquatic wildlife. The river water is considered safe for human recreation.  

 

    

 

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Fertilizer spill kills up to 20,000 fish in Maumee River, reports say. Bailey Gallion, Columbus Dispatch. July 15, 2026. Fertilizer spill kills up to 20,000 fish in Maumee River, reports say