This August's heatwave is putting air quality to the test in several Spanish cities. Tropospheric ozone, the pollutant that forms when sunlight and high temperatures react with other gases, has led Valladolid to raise its emergency protocol and Madrid to become the talk of environmental groups due to its repeated instances of non-compliance.
Valladolid activates phase 2 of ozone warning
The Valladolid City Council, through its Environmental Service, has reported that on Wednesday, August 18, the threshold of 120 µg/m³ was exceeded for the third consecutive time at the RCCAVA monitoring stations. This has triggered the activation of 'Situation 2, Alert' , which is implemented according to the Action Plan for Alert Situations due to Urban Air Pollution.
The episode began on August 12, when 'Situation 1' was declared after concentrations exceeded 100 µg/m³ for three days. Since then, the concentrations have not let up, and monitoring stations have reported readings such as 130-135 µg/m³ in Vega Sicilia, or 124 µg/m³ at the Puente de Poniente over the weekend.
Restriction measures and sustainable mobility
With the warning phase underway, the city council has approved a package of measures that will come into effect tomorrow, Thursday the 20th, if pollution levels do not decrease. The most significant measure is the reduction of the speed limit to 30 km/h within the Low Emission Zone (LEZ) and on the dual carriageway bordering it, which includes promenades such as Isabel la Católica, Rondilla de Santa Teresa, Gondomar, and Doctrinos Street.
Another important measure is making park-and-ride facilities on the outskirts of town free of charge, to encourage the use of public transport. In addition, AUVASA bus lines will be reinforced, especially those connecting to the Low Emission Zone (LEZ), and the fleet of available bicycles will be increased. The city council is asking drivers with B and C vehicle stickers not to voluntarily enter the LEZ, a measure of public support.
Madrid: a dark year in terms of ozone limits
The other major alert comes from the capital. Ecologists in Action has released data from Madrid's monitoring network: all 13 stations have already exceeded the annual number of days exceeding the limit set by European regulations, which limits pollution to 25. The Casa de Campo station is the worst affected, with more than 60 days above 120 µg/m³, compared to 66 in 2024 and 67 in 2025.
The organization asserts that ozone pollution seriously affects health , potentially reducing respiratory capacity by up to 20% and also impacting vegetation and crops. They are calling for better information for the public and criticizing the "inaction" of government authorities. For its part, the Madrid City Council responds that ozone is a complex pollutant with transboundary effects and that its origin is not solely local. They also point out that they have an alert system, an app, and protocols in place to issue warnings when ozone levels reach 160-180 µg/m³.
Health recommendations to protect your health
With such high levels, the Valladolid City Council and most organizations advise reducing strenuous outdoor activities , especially during the hottest hours of the day (from 12 pm to 18 pm). People with asthma or respiratory illnesses should strictly adhere to their medication regimen and avoid going out if they have a cough or discomfort, while those with heart problems may experience fatigue.
For the general public, it is recommended to limit strenuous outdoor exercise during these hot periods. If a cough, sore throat, or shortness of breath occurs, it is best to seek shelter indoors with fresh air. Real-time information can be found on the municipal website and the 'Vallaire' app, as well as on each city's official channels.
In short, this episode demonstrates that ozone control requires both political measures and changes in personal habits . Valladolid has already taken action with mobility restrictions, while Madrid faces a chronic situation that exceeds legal limits and demands a firm response. Until the heat subsides, alerts will continue, so a prudent attitude and everyone's cooperation will be key to keeping levels under control.
