The management of increased solid waste in wastewater It has become one of the most critical issues for urban sanitation in Malaga. The latest data from the Malaga Municipal Water Company (Emasa) shows that, far from subsiding, the problem remains very much present in the sewer network and wastewater treatment plants.
During the last year analyzed, the city had to cope with the withdrawal of 2.345 tons of solid waste from wastewaterThis figure, which is high in itself, takes on even greater significance because it represents an increase after several years of decline, and it once again puts the focus on the daily habits of citizens and the impact of rain events on the sanitation network.
A rebound that breaks the downward trend
According to data provided by the Malaga Municipal Water Company (Emasa)In 2025, they were removed from the sanitation network and wastewater treatment plants. 2.345 tons of solid wasteall of them originating from the city's wastewater. This represents an increase in 6,7% compared to the 2.197 tons of 2024This interrupts the downward trend that had been observed in recent years.
In previous exercises, the number of steps had gone from about 3.721 tons of waste collected in 2017 figures around 2.300 tons, with 2.341 tons recorded in 2023. This sustained decrease suggested an improvement in dumping habits and a positive effect of the investments made, but the rebound in 2025 shows that the problem is still far from being solved.
Much of this increase is explained by the combination of bad toilet use habits and specific weather conditions. Emasa points out that 2025 was marked by several periods of rain that favored the runoff into the sanitation network of waste accumulated during drier periods, despite regular cleaning and maintenance work.
The consequence is that, despite the measures implemented to reduce weight and volume of waste Through compaction systems and improvements to removal equipment, the total volume of waste ending up in the landfill has grown again, generating additional strain on urban sanitation infrastructure.
For the Malaga City Council, this data is a wake-up call that reinforces the need to to involve the population more in responsible use of the sewer system, preventing the toilet from being used as a trash can and thus curbing a trend that, if consolidated, could affect not only the environment, but also the maintenance bill of the service.
Wipes and other non-biodegradable waste at the heart of the problem
Emasa emphasizes that the most of the solids that appear in wastewater it has its origin in everyday hygiene products that end up in the toilet improperly. Among them are the wet wipes, cotton swabs and sanitary padsas well as other non-biodegradable waste that should never be flushed down the toilet.
Although some of these products are marketed with ambiguous messages about their supposed “biodegradability"Or regarding the possibility of flushing them down the toilet, the reality is that they behave like foreign objects in the sewage system. They don't break down as easily as toilet paper and end up forming blockages and accumulations that impede the flow of water."
These traffic jams cause pumping equipment breakdowns, pipe blockages and operational problems both at the treatment plants and in the main sewer lines. This is compounded by environmental impactsince some of these wastes can reach the natural environment in specific episodes, especially when storm releases or overflows occur in the network.
The non-biodegradable nature of this waste implies that remain intact for long periods within the sanitation infrastructure, they adhere to other solids or become entangled in mechanical elements. This results in equipment downtime, the need for manual intervention, and premature wear of pumps and filtration systems.
In short, behind the figure of 2.345 tons there is a very clear pattern: seemingly innocuous daily habitssuch as throwing away a wipe after use, become a large-scale structural problem for the city, with economic consequencesenvironmental and operational.
Where the 2.345 tons are captured: network, treatment plants and pumping stations
The total volume of solid waste removed is not concentrated at a single point in the system, but is distributed throughout the different phases of urban sanitationThe detailed data shows how the sewer network, wastewater treatment plants (WWTPs) and pumping stations (BSSs) act as successive filters.
Of those 2.345 tons of waste, approximately the 33,8%, that is, some 793,3 tonnes , it was eliminated in the periodic cleaning of the municipal sanitation networkThese actions are carried out on a scheduled basis to prevent blockages, improve the flow of wastewater and remove solids that accumulate in the collectors.
The largest block, a 40,1% of total (equivalent to some 940,7 tonnes ), was detained in the screening systems of the wastewater treatment plants of Guadalhorce and Peñón del CuervoThese devices, located at the entrance of the treatment plants, act as a first barrier that intercepts larger debris before it enters the biological and mechanical water treatment processes.
The remaining percentage, around 26% (611 tons), was evacuated from the wastewater pumping stations (WWPS) These facilities, distributed throughout the city and equipped with solid waste removal systems, are key to pumping wastewater to treatment plants, especially in areas with slopes or long distances, and are directly affected by the presence of unsuitable waste.
This distribution shows that the The pressure on the entire sanitation system is considerable.from the collectors to the final treatment equipment. Furthermore, it highlights that any improvement that reduces the amount of solids reaching the toilet would have a positive ripple effect at all stages of the process.
An economic cost of approximately 1,9 million euros per year
Beyond the tonnage figures, the massive presence of solid waste in wastewater has a direct impact on the sanitation service economyEmasa estimates that cleaning the networks, removing this waste, and transporting it to the landfill represent an annual expenditure of approximately... 1,9 millones de euros.
This amount includes the collector cleaning operationsThis includes the removal of solids from pumping stations and wastewater treatment plants, as well as the transport of waste to the Los Ruices Environmental Center, where it is properly managed. This is a recurring cost, to which must be added additional investments to renew or reinforce infrastructure.
The effect of waste is not limited to direct costs. occurrence of breakdowns and forced stops The maintenance of pumps, sieves, and other equipment also entails indirect costs, both for repairs and for the need to have on-call personnel and resources to address incidents. This forces the allocation of part of the budget that could be used for service improvements to resolving avoidable problems.
The City Council and Emasa insist that, if the amount of solids entering the toilet could be significantly reduced, it would be possible to alleviate the economic burden on the sanitation systemIn the long term, this would translate into a more efficient network, lower repair costs, and more sustainable management of public resources.
In a context where many European cities are seeking to optimize their water and sanitation infrastructure, the case of Malaga illustrates the extent to which Small individual gestures have a reflection in municipal accounts and in medium and long-term investment planning.
Investments in sieves, roughing and modernization of the system
To cope with the growing volume of solid waste, Emasa has been promoting for several years Specific investments in removal and compaction equipmentThe objective is twofold: on the one hand, to intercept as much waste as possible before it damages the facilities; on the other, to ensure that the waste that is eventually taken to the landfill has a lower water content, thus reducing its weight and volume.
One of the most outstanding performances has been the Installation of new screens at pumping stationsThese devices act as filters that capture wipes, plastics, and other solids before they can reach the wastewater treatment plants, minimizing blockages and downtime of critical equipment. This measure has been progressively extended to different wastewater treatment plants throughout the city.
At the same time, the company is working on the Implementation of screening systems at storm relief pointsThese points, which allow for the discharge of some of the flow during periods of heavy rainfall when the network becomes overloaded, are particularly sensitive to the presence of solid waste. Incorporating screening equipment helps retain a significant portion of this material, reducing the risk of it ending up in natural waterways or the sea.
The improvements are not limited to the installation of machinery. Emasa has also been orienting its strategy towards optimization of waste compaction and drying processesso that its subsequent management is more efficient. This translates into fewer transport trips, lower energy consumption associated with waste handling, and a more rational use of treatment facilities.
Despite these investments, the increase recorded in 2025 highlights that technology alone is not enough. Local authorities emphasize the need to combine infrastructure renewal with changes in citizens' habitsespecially regarding the use of the toilet as a disposal point.
Awareness and environmental education campaigns
Aware that much of the problem originates in homes, the Malaga City Council and Emasa have reinforced their citizen awareness campaignsThe idea is simple: remember that the toilet is only meant to receive water, urine, feces and toilet paper, and that the rest of the waste should go in the bin or specific containers.
These campaigns are structured through Informative messages in local media, social networks and urban displaysbut also through more direct actions in the educational environment. The Environmental Sustainability Area organizes activities in schools and universities to explain, in a practical way, what happens to wipes and other waste once they are flushed down the toilet.
In addition, initiatives are carried out in collaboration with neighborhood associations and various social groupsAmong these activities, guided tours of the wastewater treatment facilities stand out, where participants can see firsthand the amount of waste that arrives every day and the effort involved in removing it.
The City Council insists that the Citizen involvement is key To reverse the upward trend recorded in 2025. Reducing the disposal of wipes, cotton swabs, sanitary pads and other single-use products not only benefits the environment, but also helps to keep the sanitation network in better condition and contain maintenance costs.
Although there is still room for improvement, local authorities believe that the continuing environmental education It is the most effective way to change ingrained habits and move towards a more sustainable sanitation system, aligned with the objectives of responsible water management pursued in Spain and the European Union.
The scenario depicted by the 2.345 tons of solid waste removed from Malaga's wastewater makes it clear that the combination of technical investments, operational control, and changes in citizen habits It is the only way to alleviate the pressure on the sanitation network. The city faces the challenge of continuing to modernize its infrastructure, while promoting more responsible toilet use and strengthening environmental education, in order to reduce both the economic impact and the environmental consequences of a problem that, although invisible at first glance, is very much present beneath the streets.
