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Canal de Isabel II opens the doors of integrated water cycle management facilities to the people of Madrid

null Canal de Isabel II opens the doors of integrated water cycle management facilities to the people of Madrid

Canal de Isabel II opens the doors of integrated water cycle management facilities to the people of Madrid


This government-owned company is offering 480 free tickets to visit four of the most representative water management facilities in the region

  • The company is organising free guided tours of four of its facilities, on 29th and 30th June
  • For the first time, the people of Madrid will be able to visit the Arroyofresno storm tank and the Santa Engracia storage tank
  • The El Atazar dam and the El Bodonal treatment plant in Tres Cantos complete the programme of visits

On the last weekend of June, Canal de Isabel II will hold a series of open days at its integrated water cycle management infrastructure facilities in the Madrid Region. In particular, the public is invited to visit free of charge the El Atazar dam, the El Bodonal drinking water treatment plant in Tres Cantos, the 2nd Storage Facility or Underground Storage Tank on calle de Santa Engracia and the Arroyofresno storm tank.

The tours are free and will last approximately 45 minutes. They will be led by specialised monitors who will explain the operation of each installation and its role in the integrated water cycle. There will be two tours at each of the facilities, and there will be a bus service from Canal’s headquarters (calle Santa Engracia, 125) to the storm tank, the dam and treatment station.

Advance booking is required and can be done free of charge from today using this link. The 480 tickets will be allocated on a strictly first-come-first-served basis. NO MORE TICKETS AVAILABLE SINCE JUNE 19th 2019


Located on the river Lozoya, the El Atazar dam, in service since 1972, is the largest in the Madrid Region: it is 134 metres high and can store up to 425 cubic hectometres of water. It has over 8 km of galleries inside and it is monitored continuously so that the data collected by its measuring instruments can be monitored on site by Canal technicians and also sent in real time to the company’s Control Centre in Majadahonda.

The Santa Engracia Street tank is the oldest functioning tank in Madrid. This facility is located between four streets: calle Santa Engracia, calle Ríos Rosas, calle Bravo Murillo and calle José Abascal. It is also the site of the company’s headquarters. It went into service in two phases: the north compartment in 1876, and the south in 1879. It can hold over 188,000 m2 of water and its interior is furrowed with columns and arches of granite and brick.

The El Bodonal Drinking Water Treatment Plant (DWTP) is 50 years old this year. It treats water from the rivers Lozoya, Jarama and Sorbe, as well as from the well field at Torrelaguna. It can supply 4000 litres a second of high-quality drinking water into the distribution network.

Finally, and now on the sanitation side, Canal will show a storm tank, Arroyofresno storm tank, for the first time. These facilities are huge underground reservoirs created to store the first rainwater. In this way, these installations prevent treatment plants from becoming overloaded and having to discharge excess water untreated into receiving watercourses.

Canal de Isabel II currently manages 65 storm tanks in the Madrid Region, with a storage capacity of 1.53 cubic hectometres. Of these, 29 are located in the municipality of Madrid, and two of them, Arroyofresno and Butarque, are the largest in the world: each can store 400,000 m2 of wastewater, a volume greater than that of the Torre Picasso tower.


With this initiative, Canal de Isabel II is working to strengthen its commitment and closeness to society by showing people how their water is processed before reaching their homes and after it is taken away, to help them understand the importance of using it in a rational and sustainable way. This kind of action is part of Item 7 of the company’s Strategic Plan, which aims to bring the company closer to the public.

Canal de Isabel II was founded over 165 years ago, to supply water to the city of Madrid. It employs over 2800 people who work every day to serve more than 6 million people in the region. It is an innovative company, a leader in its sector and recognised worldwide for its management of the integrated water cycle.

It operates 13 reservoirs; 78 groundwater catchments; 17,556 km of water supply and distribution network; 131 drinking water and 133 wastewater pumping stations; 14,956 km of sewage networks; 65 storm tanks; 877 km of collectors and discharges; 157 wastewater treatment plants; and 588 km of reclaimed water network.

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