West Hills Area STP - North Buffalo Township, Pennsylvania Wastewater Treatment Plant

West Hills Area STP is a municipal wastewater treatment plant located in North Buffalo Township, Armstrong County, Pennsylvania. It serves a population of approximately 6,855 residents, classifying it as a small to medium-sized facility under US regulatory frameworks. As a US-based plant, it operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Pennsylvania Department of Environmental Protection. For facilities of this scale, secondary treatment is typically required, with additional nutrient removal standards in sensitive watersheds. The plant discharges treated effluent into local waterways within the Allegheny River basin, which flows into the Ohio River and ultimately the Mississippi River system. This drainage supports diverse aquatic life and provides drinking water for downstream communities.

The plant's treated effluent enters the Allegheny River watershed, a major tributary of the Ohio River. The Allegheny River supports diverse fish populations and is an important migratory corridor for aquatic species. Downstream, the Ohio River flows into the Mississippi River, which drains into the Gulf of Mexico, contributing to the vast Mississippi River Basin ecosystem.