Lagares WWTP (Vigo). Spain’s largest WWTP with biofiltration technology and one of the largest in Europe

The new Lagares Wastewater Treatment Plant (WWTP) forms part of the “Vigo Sanitation Plan”. It has a treatment capacity of up to 800,000 population equivalent, prevents direct discharges into the estuary and complies with the stringent discharge parameters set out in European legislation. This sanitation and wastewater treatment project in Vigo included the construction of a 3.8-kilometre marine outfall, with terrestrial and subsea sections, and the extension to the electrical installations of the facility. The design and construction of this state-of-theart facility also included landscaping and environmental integration criteria. In order to achieve better integration with the surrounding areas, a third of the 60,000 square-metre surface area of the plant (equivalent to six football pitches) was built underground. In addition, the new Vigo WWTP is now Spain’s largest facility implementing biofiltration technology and amongst the largest in Europe.

The new Lagares Wastewater Treatment Plant (WWTP) forms part of the “Vigo Sanitation Plan”. It is the result of the response to the serious pollution problems of the Vigo Ria (estuary) on the part of the three public authorities involved: the Spanish Ministry of Ecological Transition (MITECO), through state company Aguas de las Cuencas de España (ACUAES), the Regional Government of Galicia and the Vigo City Council. These pollution problems had led the European Union to propose a serious financial sanction for the Kingdom of Spain in 2005 for failure to comply with Directive 79/923/EEC in relation to water quality requirements for shellfish breeding.

The project design bases also demanded: a solution to the problem of faecal pollution detected in the estuary; compliance with the requirements set out in Directive 91/271/EEC for sensitive areas of over 100,000 p.e.; the capacity to treat flows of up to 12 m3/s; and endowing the new plant with a treatment capacity in pollution terms of up to 800,000 p.e. (horizon year 2042), making it the largest WWTP in Galicia.

The high effluent quality standards required, along with the demanding environmental and design requisites for the new WWTP justified the quest for innovative process alternatives and the incorporation of some of the latest WWTP design technologies.





Plant Report published in: #53 FuturENVIRO September 2018