CASTINE WPCF - Secondary Wastewater Treatment Plant in Castine, Maine

CASTINE WPCF is a municipal wastewater treatment facility located at 184 Court Street in Castine, Hancock County, Maine. The plant serves a population of approximately 1,100 residents, making it a small-scale facility typical of coastal New England communities. The plant provides secondary treatment, the standard required by the US Clean Water Act for municipal wastewater. With a designed capacity of 757.08 cubic meters per day and an average discharge volume of 340.69 cubic meters per day, the facility operates well within its capacity. As a US plant, it operates under an EPA NPDES permit issued by the Maine Department of Environmental Protection, which sets effluent limits to protect water quality. The plant's treated effluent is discharged into the local watershed, which drains into Penobscot Bay and ultimately the Gulf of Maine. This coastal discharge location requires careful management to protect marine habitats and shellfish beds. The facility plays a key role in maintaining water quality in the ecologically sensitive coastal zone of eastern Maine.

CASTINE WPCF discharges treated wastewater into the Penobscot Bay watershed, which flows into the Gulf of Maine. This coastal region supports diverse marine life including lobster, groundfish, and migratory seabirds. The plant's secondary treatment helps reduce nutrient loading and pathogen risks to the bay's sensitive estuarine ecosystem.