Earlville STP - Advanced Wastewater Treatment in Earlville, Illinois

Earlville STP is an advanced wastewater treatment facility located in Earlville, Illinois, serving a population of 1,482. The plant operates as part of the municipal infrastructure for this small community in LaSalle County. The plant provides advanced treatment, which goes beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 1,438.45 million gallons and an actual discharge volume of 738.16 million gallons, the facility operates well within its capacity. As a US plant, it operates under the Clean Water Act and is likely permitted through the National Pollutant Discharge Elimination System (NPDES) administered by the Illinois Environmental Protection Agency. The treated effluent is discharged into a local receiving water body, which ultimately drains into the Illinois River watershed and then the Mississippi River. This contributes to the overall water quality of the region, supporting aquatic life and downstream ecosystems.

The plant's discharge enters a local waterway that flows into the Illinois River basin, a major tributary of the Mississippi River. This watershed supports diverse aquatic habitats and is important for migratory fish species. The advanced treatment helps protect downstream water quality in the Mississippi River system, which ultimately reaches the Gulf of Mexico.