Clean rain water journeys through Madrid

Constructing two tanks for the Pilillas and Moratalaz basins, totalling over 1 000 metres in length, and doubling Abroñigal’s collector B, stretching over 2 300 metres, forms the basis of this major project.

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The actions are part of plans to improve the quality of the Manzanares River waters by collecting rain water and treating it in a way that avoids directly discharging it into the river. Some 3 000 000 m3 of water will be treated each year.

Retaining purity

The body in charge of running the project is Madrid city council, which is clear in its intention to enhance the purification system of the Manzanares catchment area, in turn improving the quality of river waters crossing the city. The actions are included in a major infrastructure plan and involve building and upgrading mechanisms used to control pollutants from wastewater discharged into the river. With a cleaner waste water system, residents will benefit in terms of better public health.

Since the plan was introduced, several actions carried out on the two banks of the water course have already helped resolve many problems. The current project focuses on efforts on the left bank, specifically the Abroñigal basin area. Apart from the environmental benefits, the project is expected to generate socio-economic gains, including job creation, with 142 positions created in the initial construction and upgrading phase, a further three in the operational phase.

Double capacity for added security

The first main task is to double the diameter of the secondary basins of Pilillas and Moratalaz by installing in each basin a new tank designed to collect flood water, carry it along and drain it off correctly. The second task is to double the size of Abroñigal tank B. In some places, the current tank does not have the capacity required for collecting flood water; the plan is therefore to double this tank so that the entire purification system works as necessary. 

The project will help the Madrid region comply with the provisions set out in the EU’s Water Framework Directive on water policy actions, notably wastewater treatment, purification measures and ensuring that water returns to the system in acceptable sanitary conditions.

Draft date