A Projection of Environmental Impact of a Low Emission Zone Planned in Warsaw, Poland

A low emission zone (LEZ) is a mechanism for reducing the negative impact of traffic pollution on an urban environment, where exhaust emissions are strictly regulated to meet certain environmental criteria. Such solutions increasing the sustainability of the urban environment are gaining popularity, especially in Western European agglomerations, where there are currently more than 300 zones, mainly in Italy and Germany. Thus far, there are no LEZs in Eastern and Central European countries, but Warsaw authorities plan to launch an LEZ in 2024. According to the ongoing project, the zone is to be implemented gradually, in five stages between 2024 and 2032, and the emission criteria will be tightened accordingly. The gradually reduced emissions of NO X and PM were utilized as the input dataset in the regional CALPUFF model predictions to calculate the concentrations of these main traffic-induced pollutants within the zone. The direct effect is a reduction in air pollution in the urban center, which is the area most exposed to pollution risk due to heavy traffic. Computer simulations reveal that implementation of the zone in Warsaw will result in a significant reduction in NO X concentrations within the LEZ, such that its mean concentration in the zone becomes comparable to the rest of the conurbation. However, it will bring only a slight reduction in PM 2.5 concentrations. This results from the long-standing dominance of coal combustion in the Polish economy. This also applies to the urban municipal sector, being clearly predominant over the road traffic contribution. Balance can be achieved once the de-carbonization process has been completed.