Understanding perceived tranquillity in urban Woonerf streets: Case studies in two Dutch cities

Within the current urbanised society, the call for calm and quiet areas seems more pressing than ever. Such tranquil environments like the Woonerf streets in the Netherlands allow a more human-centred design, where traffic has a restricted speed limit of 15 km/h, while pedestrians and cars share the street without segregation. In the past, predictive models have been developed to assess the tranquillity levels based on indices related to noise exposure and the amount of greenery measured through the Green View Index. However, the urban environment encompasses multiple sound sources with people having different reactions towards the auditory stimuli. Because of this complexity, objective sound measurements are examined in combination with the subjective perception of noise through eight perceptual attributes. This is done by collecting audio and visual data in 61 Woonerf streets in the cities of Groningen and Leeuwarden, supported by additional questionnaire data gathered from the corresponding residents of the above-mentioned areas. Within the context of Woonerf streets, results indicate that sound levels are perceived as relatively pleasant and uneventful. Furthermore, a difference is observed between the predicted and subjective tranquillity.