ANNVILLE TWP STP - North Annville Township, Pennsylvania Wastewater Treatment Plant

ANNVILLE TWP STP is a municipal wastewater treatment plant located in North Annville Township, Lebanon County, Pennsylvania. It serves a population of about 4,700 people, placing it in the small-to-medium agglomeration category typical of rural Pennsylvania communities. The plant is situated along US 422 and contributes to the region's water infrastructure. As a US facility, the plant operates under the Clean Water Act, which requires National Pollutant Discharge Elimination System (NPDES) permits for all point-source discharges. For plants of this scale, secondary treatment is the standard requirement, though specific treatment processes and capacity details are not publicly available. Typical facilities serving similar populations in Pennsylvania have capacities ranging from 1 to 3 million gallons per day. The plant's treated effluent likely discharges into a local stream or tributary within the Susquehanna River basin, which ultimately flows into the Chesapeake Bay. This makes the plant part of a larger watershed management effort to reduce nutrient and sediment loads to the bay, a critical estuarine ecosystem. The plant's performance is subject to state and federal oversight to protect downstream water quality.

The plant is located in the Susquehanna River basin, which drains into the Chesapeake Bay, the largest estuary in the United States. The Chesapeake Bay watershed is ecologically sensitive, supporting diverse aquatic life and important fisheries. Nutrient pollution from wastewater plants is a key concern, as excess nitrogen and phosphorus can cause algal blooms and hypoxia. The plant's discharge, though small, contributes to the cumulative load managed under the Chesapeake Bay Total Maximum Daily Load (TMDL) program.