Donald James Warnke, Sewage Sludge Dumping, IA 2024

Donald James Warnke, 64, of Sumner, Iowa, pleaded guilty yesterday in federal court in Cedar Rapids to the illegal disposal of sewage sludge from the City of New Hampton’s Wastewater Treatment Plant. The conviction stems from a deliberate act of environmental disregard that violated federal regulations designed to protect public health and the environment.

On June 19, 2015, Warnke knowingly dumped domestic sewage sludge into an open field—a flagrant breach of federal law governing waste from publicly owned treatment works. The sludge, a byproduct of municipal wastewater processing, contains harmful pathogens and pollutants that require strict handling and disposal protocols. Instead, Warnke chose to bypass them entirely, treating farmland like a personal dumpsite.

At his plea hearing, Warnke admitted to the unlawful act, confirming that he had full knowledge of the material’s origin and the rules surrounding its disposal. Federal authorities say the dumping posed a direct risk to soil and groundwater, potentially endangering nearby communities and agricultural operations.

Warnke now faces up to three years in federal prison, a fine of not less than $5,000 but not more than $50,000 per day of violation, a $100 special assessment, and one year of supervised release following any imprisonment. Sentencing has been delayed pending a presentence investigation report, and he remains free under court-ordered conditions.

The case was investigated by the Environmental Protection Agency’s Criminal Investigations Division and is being prosecuted by Assistant United States Attorneys Tim Vavricek and Matt Cole. The charges highlight the federal government’s increased scrutiny of environmental violations, especially those involving public infrastructure and health risks.

The case, filed under 16-CR-2054-LRR in the U.S. District Court for the Northern District of Iowa, underscores how seemingly obscure environmental statutes can land offenders in federal court. Chief Judge Linda R. Reade will preside over sentencing. Court records are accessible via the Northern District of Iowa’s electronic filing system.