A study on Lisbon waterfront urban public space soundscape

Waterfront areas can provide ample possibilities as restorative sites that contribute to improve people's quality of life. In this sense, their soundscape becomes an important perception factor to be considered in their analysis or urban space planning process. Nevertheless, how the waterfront sound environment is perceived by the users has been scarcely studied. In order to understand the soundscape perceptive process related to waterfront public spaces, from the user’s perspective, a study of 10 Tejo River waterfront urban public spaces in the city of Lisbon, Portugal, was carried out. Sound source identification started with a soundwalk programme which also helped the site selection. Sound environment data were recorded and a questionnaire was applied to 500 users. The sound recordings and the users’ responses were analysed in the laboratory, where the predominance of each perceived sound source was identified and quantified. Despite the fact that all studied public spaces featured a direct relationship with the river, and perhaps since local traffic sounds generally dominate the acoustic environment, only in some sites the waterfront characteristic sounds (water, boats, seagulls, pier) were those most frequently identified by the users. Here, the more perceived sound sources, mostly natural sounds and those related to the waterfront, produce a masking effect relative to other sounds that were detected as having a higher temporal predominance in the laboratory. The research results were correlated with other user’s subjective evaluations, in order to better understand the waterfront public space soundscape appreciation process.