Fithian STP - Secondary Wastewater Treatment in Vermilion County, Illinois

Fithian STP is a municipal wastewater treatment plant located in Vermilion County, Illinois, United States. The facility serves a small population of 506 residents in the rural community of Fithian and surrounding areas. The plant provides secondary treatment, which is the standard level required by the U.S. Clean Water Act for municipal wastewater facilities. With a designed capacity of 264.98 thousand cubic meters per year and an actual discharge volume of 189.27 thousand cubic meters, the plant operates below its design capacity. As a small facility, it is subject to National Pollutant Discharge Elimination System (NPDES) permitting under the Illinois Environmental Protection Agency. The treated effluent from Fithian STP is discharged to local waterways that drain into the Vermilion River, a tributary of the Wabash River, which ultimately flows into the Ohio River and then the Mississippi River. The plant plays a role in protecting water quality in the Wabash River basin, supporting aquatic life and downstream ecosystems.

The plant discharges into the Vermilion River watershed, which flows into the Wabash River, a major tributary of the Ohio River. The Wabash River supports diverse aquatic species and provides habitat for migratory fish. The region's agricultural land use can contribute nutrient runoff, making the plant's secondary treatment important for controlling biochemical oxygen demand and suspended solids in the receiving waters.