Lorraine Williamson
As Conchas, a reservoir in Galicia, is facing a severe environmental crisis that is endangering both local wildlife and human health.
The contamination is primarily caused by high levels of dangerous bacteria and toxic substances, with alarming findings from CSIC and Complutense University of Madrid researchers. The crisis has prompted local residents to file a lawsuit against regional authorities, including the Xunta and the Hydrographic Confederation of Miño-Sil and Limia, seeking urgent action.
Toxic bacteria and high pollution levels
According to the latest research, As Conchas is home to dangerously high concentrations of bacteria, some of which are resistant to antibiotics. In certain areas of the reservoir, up to 97 million harmful bacteria have been detected per litre of water. This concentration is equivalent to 97,000 bacteria per millilitre. The researchers warn that these bacteria are not only harmful to the environment but also pose a direct risk to public health, especially for those who swim or engage in water sports in the area.
Health risks and environmental impact
The water in the reservoir contains harmful substances such as microcystins and legionella, which are capable of causing diseases. These bacteria can spread through direct contact with water, resulting in symptoms like dizziness, skin irritation, and difficulty breathing. Additionally, the reservoir releases toxic gases, including methane and hydrogen sulphide, which contribute to climate change and pose further risks to health.
Research also reveals concerning trends in local health. People living near the reservoir have a higher incidence of serious diseases, including liver and colon cancer. In particular, women in the area appear to be more vulnerable to these conditions than those in other parts of Galicia.
Cyanobacteria and its impact on wildlife
The growth of cyanobacteria in the reservoir has been increasingly prevalent since 2011, particularly during the warmer summer months. These bacteria deplete oxygen in the water, leading to the death of fish and mammals. The reservoir also emits a strong, unpleasant smell due to the presence of hydrogen sulphide, a gas that contributes to environmental degradation. Despite being a protected nature reserve, the area’s biodiversity is being harmed by waste from intensive agriculture and poor waste management practices.
Antibiotic resistance and future threats
Another growing concern is the development of antibiotic-resistant bacteria in the reservoir. The widespread use of antibiotics in agriculture has led to the contamination of the water with these chemicals. As a result, some bacteria have become immune to treatment, posing an even greater threat to human health and complicating efforts to address the pollution.
Urgent need for action
Scientists are sounding the alarm about the escalating crisis in As Conchas, highlighting that the pollution levels are worse than those in other notoriously polluted areas, such as the Guadalquivir estuary. The situation requires immediate intervention to prevent further environmental damage and safeguard local residents’ health.