You probably have heard how in 2016 Barcelona introduced the idea of "superblocks", which aimed to create car-free zones by routing traffic around multi-block areas. Since then the city has planted trees to add green spaces, increased the area of pedestrian space and public spaces.
However you might not be aware that during the project SUMBA+ the Free and Hanseatic City of Hamburg and here the district of Altona (Germany) is creating a framework on how to build so-called quiet areas (working title) in the central area of Altona. This is an additional approach to support the transformation towards more Active Mobility.
As you probably can imagine a big part of the noise pollution in city centres stems from individual motorized transport. A regular sized car driving 50km/h is 70db, which is considered loud. In comparison, a passing car driving 30km/h is 60dB, which is a moderate amount of noise. A passing truck is 90dB, already considered very loud. Extremely loud noise above 120 dB can harm your ears. It is estimated that the threshold for health risks of long-term noise pollution is 65dB during the day and 55dB during the night. That is quite a difference when we are looking at the numbers of decibels caused by vehicles. In addition, industry, leisure establishments and school/day care facilities also contribute to the overall noise level of an area.
The framework of quiet areas aims to map these different sources of noise and find out if and how these can be mitigated in order to create an area with less noise pollution. However measures of action for new and existing districts differ. The first choice of action is of course settlement and district planning, which includes zoning and distribution of use according to noise sensitivity. It's also important to direct urban development by regulating the position and height of buildings and facade design. In some cases the best thing to do is noise abatement by constructing noise protection walls. In terms of urban planning safeguarding and developing quiet spaces is paramount to maintain generally accessible quiet areas within walking distance.
However when all of these courses of action are unattainable for the city planners traffic avoidance and inducing modal shift is most cost-effective and fastest approach to create quiet areas. This measure means promoting low-noise modes of transport and intermodality, restricting traffic, regulating speed and also includes spatial redistribution and parking management. Altona analysed the different means of interference in order to create a quiet area. Also the accessibility of relevant transfer points in Quiet Areas in the central area of Altona to Altona railway station were studied.
Summary of the results is available in English. The full study in German can be accessed here:
https://sumba.eu/en/page/hamburg-altona-and-pinneberg-county