To ensure the best water supply service to the three million inhabitants of the metropolitan area, the AMB has a complex facilities network distributed throughout the metropolitan geography.

Water cycle infrastructures
Through an extensive transport network, previously captured and purified water is distributed to users. Once used, wastewater, together with rainwater, is collected through municipal sewers. Sewer pipes network carries such water to treatment plants, where it is treated before being reused or returned to the environment.

Water cycle facilities

  • Supply
    Water is mainly obtained from surface sources (81%) of the basins of Ter and Llobregat Rivers. It is also collected from underground water sources (15%) through more than 60 wells, distributed among the aquifers spread across the lower valley and the delta of Llobregat River and managed by different companies.

    The desalination plant of Llobregat basin, managed by the public company Aigües Ter Llobregat (ATLL) mandated by the Agència Catalana de l'Aigua (Catalan Water Agency), produces 200,000 m3 of water per day.

    Once collected, water is transported to different ETAPs (Drinking Water Treatment Plants). The three main ETAPs are located in Sant Joan Despí, Abrera and Cardedeu, outside the metropolitan area; there are also 10 smaller ones.

    Once water is drinkable, it is distributed to 36 municipalities in the metropolitan area, through a distribution network comprising 5,500 km of pipelines and 150 header tanks, which can store up to 540,000 m3 of drinking water.
  • Sanitation
    Wastewater is collected in sewerages that are managed by municipalities. A sewer pipe network connects the sewerage system to purifying treatment plants. In the metropolitan area there is a sewer pipe network of 3,000 km, 300 of which are managed by the AMB, while the rest is managed by each municipality.

    In the AMB there are seven EDARs (Wastewater Treatment Plants). The AMB is responsible, through the public company EMSSA, for evacuating, treating and sanitising an average of 11,000 litres of wastewater per second, 24 hours a day and 365 days a year.
  • Reuse
    ERAs (Water Regeneration Stations) carry out the required treatments so as to give water new uses that do not require drinking water: irrigation, urban cleaning, and environmental and industrial uses. The AMB has four ERAs, located in the EDARs of Baix Llobregat, Gavà, Sant Feliu de Llobregat and Montcada.
  • flood prevention
    The sewerage and sewer pipes network, which collect wastewater and have a large storage capacity, have also the function of draining rainwater (specially in developed areas).

    Besides, the AMB has a series of infrastructures specifically designed to prevent flooding. Retention tanks and flood lamination ponds accumulate rain water and, once full, release it slowly and gradually. It also has anti-DSU systems that avoid water going out of the sewerage system.