Noise pollution above the maximum immission values affects well-being and represents a significant health risk. In addition to the known impact on psychological health - stress, irritation, tension - noise can also lead to physical problems such as raised heart rate and elevated blood pressure.
Noise pollution results in health costs, loss of rent and reduced property prices, as lower rents are paid in noise-polluted areas. In 2005, the total economic cost of noise was thus estimated at over CHF 1 billion per year. Finally, noise levels also lead to changes in the composition of the local population: those who can afford to do so move to a quieter neighbourhood.
The second largest problem (after road noise) is rail noise. Above all it is those who live or work next to railway tracks that are affected. Rail noise is particularly onerous at night.
During the day, 70,000 people and, at night, 140,000 people are exposed to hazardous or undesirable rail traffic noise. 90% of these people live in cities or built-up areas.
Since 2000, new noise abatement measures have been implemented on the Swiss rail network; this means that many people no longer suffer from noise pollution. Measures regarding rolling stock, the construction of noise barriers and, as an additional measure, the introduction of soundproof windows have been implemented. The goal of noise abatement has thus not yet been fully realised. Problems continue to be caused by international rail freight traffic, which for reasons of cost has not seen the conversion of all rolling stock to low-noise units.
The situation is likely to improve in the future: legal provisions mean that newly commissioned rolling stock may only be put into operation if it uses low-noise technology. This process will be concluded in Switzerland in 2015 and at the international level in 2030.
The noise abatement strategy to date was appropriate. However, it is not sufficient to completely eliminate the problem. Future noise abatement strategies should contain additional elements, e.g.:
- Those affected by noise pollution and those responsible for policy should be better informed of the noise situation in Switzerland than previously.
- Low-noise technologies should be promoted using measures that provide a market incentive for them.
- The legally established polluter-pays principle should be strengthened, e.g. using incentive systems.
The emissions from the sources are determined in SonBase from the basic data available (emissions plan, basic geodata, statistical data, traffic data etc.). The propagation and resultant noise immissions are then determined in the noise module (CadnaA) by incorporating a digital elevation model. The immission limit value in the Noise Abatement Ordinance (NAO, CC 814.41) Annex 4 is definitive.