Holly Ridge WWTP - Secondary Treatment Plant in Onslow County, North Carolina

Holly Ridge WWTP is a municipal wastewater treatment plant located in Onslow County, North Carolina, United States. The facility serves a small population of 833 residents and operates under the regulatory framework of the US Clean Water Act, which requires secondary treatment for discharges to surface waters. The plant provides secondary treatment, a standard level for domestic wastewater that removes biodegradable organic matter and suspended solids. Its designed capacity is 984.20 volume units, and the current discharge volume is 264.98 volume units, indicating operational headroom. As a coastal facility within 10 km of the Atlantic Ocean, the plant must meet stringent nutrient and pathogen limits to protect sensitive estuarine ecosystems. The treated effluent is discharged into local waterways that drain to the Atlantic Ocean via the New River or nearby coastal sounds. The surrounding region includes the Intracoastal Waterway and estuarine habitats that support diverse aquatic life, including fish and shellfish. The plant's performance is critical to maintaining water quality in these ecologically important coastal waters.

The plant discharges into the coastal watershed of Onslow County, which drains to the Atlantic Ocean through the New River estuary and nearby sounds. These waters support diverse aquatic life, including commercially important fish and shellfish species. The proximity to the coast means that nutrient and pathogen removal is essential to prevent eutrophication and protect recreational and ecological uses.