Every year Metro saves enough water to fill eight Olympic-sized swimming pools by using recycled water to wash down trains
(WorldNews Spain)

Every year Metro Madrid saves over 20,000 cubic metres of water by using recycled water to wash down its trains and by observing the measures under the Sustainable Water Management Plan, all of which adds up to an annual saving of enough water to fill eight Olympic-sized swimming pools or the equivalent of the daily consumption of the population of Torrejón de Ardoz. Besides this, Metro Madrid also has a purification plant to treat water pollutants, such as...