Outdoor air quality study

3D digital modeling and metrology

SAS NEMAU for the city of Nîmes

June 2020

10 ha

Impact of the A9 and surrounding roads on the project


A restructuring of the Nîmes Olympique stadium has been proposed to the Nîmes City Council. This restructuring concerns the creation of a new stadium integrated in a district. The development of the new stadium as well as of the neighborhood in the vicinity is planned on the plots of the old stadium. These plots are adjacent to the A9 freeway and are surrounded by traffic routes that serve the stadium on match days as well as numerous shops and a medical clinic. Because of the proximity of these roads, sources of air pollution, AIR&D was mandated to study the air quality in the stadium area before and after development.

To do this, three-dimensional models of the dispersion of pollutants from road traffic on the A9 and adjacent roads were carried out. These models are based on a 3D Computational Fluid Dynamics (CFD) model in order to take into account the complexity of the construction project, the weather, but also the elevation of some neighboring roads. In addition, a measurement campaign was also conducted to qualify the initial state.

The modeling results showed that the A9 freeway is the main source of traffic-related pollutants in the area. Following the simulations, recommendations were made as to the location of the air vents in order to improve the indoor air quality.