The beaches of Spain are under scrutiny by the country’s authorities due to the sewage spill in Valencia’s sewer system, which has already affected more than 20 of them. Faced with the environmental danger and the health risk of these waters, Spanish authorities have decided to prohibit swimming on these coasts while their safety is being verified.
This is the third spill in a month that has affected the beaches of Valencia, so experts point to several possible reasons as the causes of this problem on the Spanish coasts.
Partly, it is believed that one of the factors is the city’s combined sewer system, where sewage and rainwater converge, which has increased in recent times as a result of the early rainy season. This causes the sewer system to overflow, leading to overwhelmed treatment plants.
On the other hand, experts believe that another possible cause of the problem is the peaks in seasonal population, as well as the existence of housing in non-urbanizable areas. The latter has been a recurring problem in the past year, causing the closure of about twenty beaches.
Combined Sewer System in Valencia, a Pollution Hotspot
Valencia has a combined sewer system that merges domestic wastewater with rainwater in the same network. This type of infrastructure, although common in many old European cities, presents significant environmental challenges, especially during intense rain events.
When a storm occurs, the system can overflow, causing direct discharges of contaminated water into the sea and natural water bodies. This untreated discharge contributes to the degradation of aquatic ecosystems and affects the water quality in beaches and rivers.
In addition to the ecological impact, overflows from the combined system also pose a risk to public health. To mitigate these effects, measures such as storm tanks and improvements in the sanitation network are being implemented, although challenges persist due to climate change and urban growth.
How to Counteract Its Effects?
One way to relieve pressure on the combined sewer system in Valencia is to incorporate nature-based solutions, such as rain gardens, green roofs, and permeable pavements. These infrastructures help absorb part of the rainwater before it reaches the network, reducing the risk of overflows.
At the household level, it is crucial to avoid pouring solid waste, oils, or toxic products down the drain, as these further contaminate the combined waters that can end up in the environment. Using less water during stormy periods also helps avoid overloading the system.
Furthermore, promoting the collection of rainwater for non-potable uses, such as irrigation, is a sustainable practice that reduces urban runoff volume. Combined, these individual and community actions help mitigate the impact of the combined sewer system on local ecosystems.
