Sheffield STL Wastewater Treatment Plant, Latimer, Iowa

Sheffield STL is a wastewater treatment facility located on Kelly Street in Latimer, Iowa, within Franklin County. The plant serves a small community of approximately 930 residents, reflecting its role in managing municipal wastewater for a rural area in the north-central part of the state. The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 529.96 volume units and a discharge volume matching that figure, the facility operates at full capacity. Under the U.S. Clean Water Act, such plants are regulated through National Pollutant Discharge Elimination System (NPDES) permits, which set effluent limits to protect water quality. The treated effluent from Sheffield STL is discharged into local streams that are part of the Iowa River watershed, ultimately draining into the Mississippi River and the Gulf of Mexico. This discharge contributes to the ecological health of downstream aquatic habitats, supporting fish and wildlife in the region.

The plant's discharge enters local waterways within the Iowa River basin, which flows into the Mississippi River and eventually the Gulf of Mexico. This watershed supports diverse aquatic life, including fish species such as catfish and bass, and provides habitat for migratory birds. The advanced treatment helps reduce nutrient loading, which is critical for preventing algal blooms in downstream water bodies.