SANT JOAN Wastewater Treatment Plant, Sant Joan, Mallorca, Spain

The SANT JOAN wastewater treatment plant is located in Sant Joan, a municipality in the Pla de Mallorca region of the Balearic Islands, Spain. The plant serves a population of 2,027 and is part of the island's wastewater infrastructure, managing domestic sewage from this inland community. As a secondary treatment facility, SANT JOAN meets the standard required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The plant has a designed capacity of 2,000 m³/day and discharges approximately 554 m³/day of treated effluent. Its capacity utilization is moderate, indicating operational headroom. The treated wastewater is discharged into the local hydrological network, which ultimately drains into the Mediterranean Sea. The plant's location inland, more than 10 km from the coast, reduces direct marine impact, but its effluent contributes to the island's water cycle and supports downstream ecosystems.

The plant discharges into the inland drainage system of Mallorca, which flows through ephemeral streams and aquifers before reaching the Mediterranean Sea. The Balearic Islands have a Mediterranean climate with seasonal rainfall, making water resources sensitive to pollution. The treated effluent supports local groundwater recharge and maintains base flows in intermittent streams, which are important for native flora and fauna.