Silence is a precious commodity. It is supposed to foster health and well-being of people and contribute to an appealing environment for working, living and leisure. In contrast, however, settlement development with dense building in Switzerland is more and more geared towards concentration, while at the same time population and traffic are increasing. These trends can increase noise, which is why increased efforts are being made in Switzerland in the area of noise protection.
Conflicts of interest may arise between noise protection and the densification of settlements required by spatial planning. Since the enactment of the Environmental Protection Act and the Noise Prevention Ordinance in the 1980s, the spatial planning problems of urban sprawl and land consumption have become more acute.
In its function as owner of the infrastructure, the community is obliged to provide effective noise protection. The deadline for the rehabilitation of main as well as minor roads expired in March 2018. In many places, the cantons and municipalities are behind schedule with the remediation measures. Local residents are therefore still exposed to immissions that exceed the permissible limits under the Noise Protection Ordinance and will probably have to take legal action to enforce their noise protection claims.
At the same time, roads that are not noise-remediated can lead to de facto construction bans. In noise-exposed areas, new buildings with noise-sensitive rooms may only be built if the building owner ensures that the immission limits are complied with. Those wishing to build have the choice of either financing appropriate noise protection measures themselves or waiting for the fixed installation to be refurbished. Since the spatial planning concerns of high-quality densified settlement development will have to be taken into account to an even greater extent in the future, construction projects that fit these criteria can be granted an exemption permit in accordance with federal court rulings. As a rule, such an exception is granted if the immission limits set out in the Noise Protection Ordinance are not significantly exceeded, provided that compliance with these limits is not achieved in a satisfactory manner from an urban planning perspective and that adequate living comfort can be ensured by means of ventilation windows on sides of the building facing away from the noise and any other measures that may be necessary. Before an exemption is granted, however, it must be demonstrated that all the structural and design measures under consideration have been examined. In particular, noise barriers made of glass or 30 km/h speed limit zones come to mind. Only when it has been established that all proportionate measures have been exhausted an exemption permit can be granted “ultima ratio”.