Mound City STP - Secondary Wastewater Treatment Plant in Mound City, Illinois

Mound City STP is a municipal wastewater treatment facility located in Mound City, Pulaski County, Illinois. The plant serves a population of approximately 1,030 residents, reflecting its role in a small community within the Mississippi River region. The plant provides secondary treatment, which is the standard biological treatment process required by the U.S. Clean Water Act for municipal wastewater. With a designed capacity of 567.81 cubic meters per day and an average daily discharge of 378.54 cubic meters, the facility operates below its capacity, indicating room for future growth or seasonal variability. The treated effluent from Mound City STP ultimately drains into the Ohio River via local tributaries, contributing to the Mississippi River basin. This region supports diverse aquatic life and is part of a major migratory corridor for waterfowl. The plant's operation helps protect downstream water quality in the Ohio and Mississippi Rivers.

The plant's discharge flows into local waterways that feed the Ohio River, a major tributary of the Mississippi River. The Mississippi River basin is ecologically significant, supporting diverse fish species and providing critical habitat for migratory birds. The secondary treatment process reduces organic pollutants and suspended solids, helping to maintain water quality in this important river system.