ARBIZU LACUNZA Wastewater Treatment Plant, Lakuntza, Navarra, Spain

ARBIZU LACUNZA is a wastewater treatment plant located in Lakuntza, within the Sakana region of Navarra, Spain. The facility serves a population of approximately 6,467 people, placing it in the small agglomeration category under Spanish and EU regulations. The plant operates under Spain's implementation of the EU Urban Waste Water Treatment Directive (91/271/EEC). For agglomerations of this size, the directive requires secondary treatment as a minimum standard, with more stringent requirements if the discharge enters sensitive areas. The plant discharges into the local watershed, which ultimately drains into the Ebro River basin. The Ebro River flows eastward into the Mediterranean Sea, supporting diverse aquatic ecosystems along its course. The treatment plant plays a key role in protecting water quality in this region.

The plant's treated effluent enters the local water system within the Ebro River basin, one of Spain's major hydrological systems. The Ebro River flows approximately 930 km to the Mediterranean Sea, where it forms a large delta that supports diverse aquatic life and important migratory bird populations. The plant's location in Navarra, a region with significant agricultural activity, means its discharge quality is important for maintaining downstream water quality standards.