Mapping of noise in the metropolis — (Day)

Realisation of strategic noise maps in compliance with a European noise directive. Noise indicators are Lden (Level Day Evening Night), a representative average 24-hour day noise indicator, and Ln (Level Night), a representative average nighttime noise indicator (22h-6h); they are evaluated at a height of 4 m. The calculation method shall be in accordance with NFS-31-133 “Calculation of sound attenuation during outdoor propagation, including meteorological effects”. * * * Noise maps help communities improve the living environment of its inhabitants. They make it possible to know the sound environment of the municipalities and assess the exposure to noise of sensitive populations and establishments (health and education institutions). Thanks to them, action priorities can be better defined in order to reduce noise pollution, as well as identify and preserve quiet areas. ##### THE MUNICIPALITIES CONCERNED In our territory, the urban area originally covered by the 2002 European directive brings together 62 municipalities. In the interests of territorial coherence, however, the European Metropolis of Lille has opted to carry out noise mappings across all of its municipalities. Technical assistance was proposed for the municipalities of Bourghelles, Cysoing, Louvil., Provin and Bauvin. #### THE CREATION OF CARDS The creation of noise maps takes place in 4 main stages: * Step 1: Data collection and formatting * Step 2: Structuring of databases * Step 3: Computer modelling and map calculations * Step 4: Edition of maps and analyses. Noise sources taken into account: road traffic, rail traffic, aviation activity, and noise from industries classified for environmental protection.