Environmental protection and Sustainability

* Environmental protection

The cities intervene decisively in the natural water cycle. The responsible management of this basic element is one of the keys to respecting the environment and its sustainability.

The Barcelona sewage system is an answer to the need for environmental protection of the receiving media: the Llobregat and Besòs rivers and the Mediterranean Sea.

The objective is to reduce and control the discharges into the sewer system to the receiving medium.

The used water is directed through the sewage system network to the purification plants, where they are treated before being flushed out.

* Sustainability

Sustainability passes through four basic aspects:

• Limiting the discharges of unitary systems to the receiving medium in times of rain.
• Filtering of wastewater in the aquifers so as to limit their contamination.
• Maintaining the balance of the ground-water level before the filtrations and infiltrations between the aquifer and the network.
• Study of the re-use of purified water, for the saving of water resources.