Canal de Isabel II has removed over 22,000 tonnes of solid waste from its treatment plants this year

null Canal de Isabel II has removed over 22,000 tonnes of solid waste from its treatment plants this year

Canal de Isabel II has removed over 22,000 tonnes of solid waste from its treatment plants this year


The company has joined the campaign ‘Don't feed the sewer monster’, promoted by the Spanish Association for Water Supply and Sanitation and supported by over 100 entities

  • The company held an event for World Toilet Day, which the UN has been celebrating since 2013
  • The public company’s average cost overruns for this type of waste come to 2 million euros a year

Canal de Isabel II removed 34,000 tonnes of solid waste from its waste water treatment plants last year. This waste corresponds to items that should never, under any circumstance, enter the sanitation network. In addition to wet wipes, the 157 waste water treatment plants (WWTPs) that Canal operates across the Madrid region have to deal with the daily arrival of products flushed down the toilet that include cotton buds, feminine hygiene products and human hair, which not only pose serious operational and economic problems but can also cause significant environmental damage.

In specific terms, as of September, some 22,000 tonnes of detritus have been extracted from the public company’s 157 treatment facilities, and the forecast for the end of this year is a total of 29,000 tonnes. This is lower than the figure recorded in 2018 when 34,000 tonnes of this type of waste was collected.

For this reason, and in conjunction with World Toilet Day, which was established by the UN in 2013 to underline the importance of sanitation networks in the conservation of the environment and the containment of diseases, Canal hosted an event at its Arroyo Culebro Cuenca Media-Alta treatment plant, where the Spanish Association for Water Supply and Sanitation (AEAS) launched the campaign ‘Don't feed the sewer monster’.

The president of the AEAS, Fernando Morcillo, was able to see how this waste is extracted during the pre-treatment phase and the problems that it causes with the facility’s machinery. During his visit, he was accompanied by Canal de Isabel II technicians and representatives of some of the companies involved in the awareness campaign promoted by AEAS.

More than 120 entities have signed declarations of commitment to this awareness campaign, promoted by the urban water sector with the aim of preventing environmental and economic problems caused by blockages and damage to homes, sewer system networks, pumping equipment and water treatment plants.


After confirming a 20 % increase in the collection of this type of waste since 2010, in the summer of 2016, Canal de Isabel II launched an information campaign to raise awareness among the public and encourage people to avoid flushing these products down their toilets and to dispose of them in the waste bin instead.

Wet wipes, along with all the other waste flushed down the toilet, pass through the interior pipework of households, where they can cause blockages. This can be especially problematic if oil and other similar items are poured into drains, contributing to the accumulation of larger build-ups. They then pass through the sewer system network and waste water pumping stations before finally arriving at the waste water treatment plants.

Despite the claim that they are biodegradable, the time taken for wet wipes to pass through the sewer system from flushing down the toilet until their arrival at the waste water treatment plant is not long enough for them to decompose, so they build up in the treatment plant inflow screens and in the pumps, especially during rainy periods. Once this waste is removed it has to be disposed of in landfill.

Flushing wet wipes can lead to serious damage not only to installations and infrastructures but also, of course, to the environment. The pumps that propel the waste water inside the treatment plants may stop functioning and, in extreme cases, plants could become inoperative. Finally, the operators who work in these facilities and on the sewer system networks are subject to significant occupational risk when they have to unclog pipes, pumps or other components.

Canal de Isabel II has calculated that these discharges to the sewer system lead to average annual cost overruns of 2 million euros. This amount includes the costs of removing the waste, the extra labour costs for cleaning the pumps, replacement of any pumps that remain inoperative and the increased energy bill.


Within the strategic framework for promoting environmental quality, Canal’s Strategic Plan for 2018-2030 includes a plan for excellence in purification - our healthy rivers - to go beyond legal compliance in our commitment to the environment and implement actions such as WWTP modelling and improved quality of discharges, as well as a plan to improve the control of industrial discharges into the network.

Canal de Isabel II was founded almost 170 years ago to supply water to the city of Madrid and today its more than 2,800 employees work every day to provide services to over 6 million people throughout the region. An innovative public company and a leader in its sector, it has gained international recognition for its integrated water management.  

The company operates 13 reservoirs, 78 groundwater abstraction systems, a 17,601 -kilometre conveyance and distribution network, 131 pumping stations for drinking water and 133 for waste water, 15,083 kilometres of sewer system networks, 65 storm tanks, 157 waste water treatment plants and a 615 -kilometre reclaimed water network.