MAMETZ SE Wastewater Treatment Plant, Mametz, Hauts-de-France

MAMETZ SE is a municipal wastewater treatment plant located in Mametz, a commune in the Pas-de-Calais department of Hauts-de-France, France. The plant serves a population of approximately 3,000 residents and is situated in the rural landscape of the region. As a secondary treatment facility, it provides biological treatment to reduce organic matter and suspended solids before discharge. The plant has a designed capacity of 4,500 m³/day and currently discharges an average volume of 535.19 m³/day, indicating it operates well below its maximum capacity. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), plants serving agglomerations between 2,000 and 10,000 population equivalent are required to provide secondary treatment, which MAMETZ SE complies with. The directive aims to protect water bodies from eutrophication and pollution. The treated effluent from MAMETZ SE is discharged into local watercourses that eventually drain into the North Sea via the Aa River basin. The region's watershed supports diverse aquatic life and is part of the broader ecological network of the Hauts-de-France. The plant plays a key role in maintaining water quality in this sensitive coastal zone, which is important for both biodiversity and human activities such as fishing and tourism.

MAMETZ SE discharges into the local river system within the Aa River basin, which flows through the low-lying plains of Hauts-de-France before reaching the North Sea near Calais. The downstream environment includes coastal wetlands and estuaries that support migratory birds and fish species. The plant's secondary treatment helps reduce nutrient loads that could otherwise contribute to eutrophication in the marine environment.