Tuesday, July 5

What if the water doesn’t fall from the sky? These are the keys to guaranteeing a sustainable supply in Madrid

Historical records already reveal that the Madrid region is suffering the effects of climate change in the form of droughts or, on the contrary, torrential rains that drag contamination from the soil. Faced with this scenario, Canal de Isabel II has prepared a comprehensive strategy that guarantees a sustainable supply of water without resorting to restrictions and reducing the water footprint.

In full commemoration of International Environment Day, Canal de Isabel II can show off its have been chosen world reference operator in water management. The news broke in early May, when the United Nations Department of Economic and Social Affairs made public the technical cooperation agreement, reached with the Madrid entity, to “work together to comply with and integrate the global objectives in water and energy matters”, as both parties pointed out. However, despite the international recognition that this alliance entails, the public company cannot lower its guard against the effects that climate change is already showing in the region.

And it is that, in the last three decades, The average contribution of water to the Madrid reservoirs has been reduced by 20% regarding the historical record started in 1914. In this sense, from Canal they specify that “this new climatic pattern requires a strategy whose objective cannot be based on increasing water resources, but must focus on optimizing those available”. To achieve this, the entity has set a consumption target of 156 liters per inhabitant per day, compared to 202 in 2021. If such a figure were reached, the Community of Madrid would have the most efficient consumption in all of Europe.

The public company has already taken previous steps on this path, since, although there has been an increase in the population supplied between 2005 and 2021 —going from 5.74 million inhabitants to 6.55—, derived water for consumption decreased by almost 20 points in the same period. This evolution has been achieved in recent years, mainly thanks to four coordinated fields of action: the promotion of the use of reclaimed water, the efficiency of the distribution network, the greater degree of automation of the systems and the awareness on the part of Madrileños.

To reduce uncontrolled water, Canal has devoted significant efforts related to monitoring the level of actual losses. The company has emphasized “minimizing the leaks produced in its water network of more than 17,000 kilometers and pursuing fraud, while monitoring the sub-metering of the meters,” they point out. In this field of action, improving distribution has been essential, with an average renewal of more than 100 kilometers of network per year.

At the same time, “a 51% decrease in pipe breakages has been achieved and the largest investment made to date has been launched: the contract for the renewal of 1,200 kilometers of supply pipes in 163 municipalities,” they indicate. from the organism.

Pollution transport in torrential rain

In the ‘top’ of concerns of Canal de Isabel II is a forecast related to climate change: the rains will be more sporadic, but more severe. Mitigating the effects of torrential rains and preventing flooding entails a significant investment in research, which has resulted in rainfall reports and studies on how pollution is transported by storm runoff.

In this way, the entity’s technicians have taken samples of different types at different points of the network to establish a map of pollution concentration. The result of the research is a system that reveals the type of rain expected, the most efficient forms of purification and the treatment that water must receive before being returned to the natural cycle.

On the other hand, before acting on the liquid itself, it is important to know when and how it will precipitate on the ground. To anticipate possible scenarios, Canal has an early detection system for intense rains based on meteorological radars, each of which covers a radius of 65 kilometers. These, after crossing their data with those obtained by the rain gauges, allow forecasting the type of rain that is coming and the affected areas up to four hours in advance. The rest of the process is completed with a special infrastructure for these situations: storm tanks, cascade treatment plants, collectors or spillways, among other facilities.

Canal’s other major line of research to mitigate the impact of runoff in large population centers is the so-called “sustainable urban drainage.” From the public company they confirm that their Center of Excellence in Research has a pioneer plant in Europe aimed at solving this problem through experimentation. In it, “the effectiveness of different drainage technologies is contrasted with the aim of retaining the first rainwater and, at the same time, reducing the volume that is transported through the sewage system”, the technicians point out. The goal is for the liquid element to reach the sanitation network as clean as possible.

The tests are carried out on an area of ​​3,000 square meters that has been divided into three zones to monitor the investigations. The first of them has four green roofs, while the second has three firm pavements and the last one houses two large ditches: the objective is to measure the quantity and quality of drained flows. In this way, studying the behavior of the water, the conclusion has been reached that “the flow that reaches the sewage network could be reduced by around 70% and the contamination carried by the rain by up to 80%”, according to estimates of the public company.