Residents of the City of Lahti in Southern Finland live close to nature. More than one in two live less than 300 metres from a quiet area. In Lahti, an area is defined as quiet when there are mainly natural sounds and no traffic noise, for example. Quiet places in Lahti include the extensive outdoor areas of Salpausselkä ridge system, many parks, and protected natural areas.
Lahti is the eighth largest city in Finland with over 120,000 residents. It is located about an hour’s train ride from the Finnish capital of Helsinki. Lahti is also the European Green Capital in 2021. Noise is one of the indicators monitored during the Green Capital year. Among other things, the aim is to protect 2,000 people living in the city’s high-noise areas and to preserve the current quiet areas in the city.
– Noise is one of the main factors reducing the quality of the living environment, and one of the greatest environmental nuisance caused by road traffic. We in Lahti are fortunate to live in fairly quiet surroundings. However, it is important to work out how we can make the living environment even safer and healthier for everyone, says Johanna Saarola, Environmental Inspector at the City of Lahti.
New bypass reduced noise in the city centre
According to Finnish standards, about 10% of residents in Lahti are exposed to road traffic noise during the day and about 7% at night (2017). Noise has been combated in the city mostly by lowering the traffic speed limits.
A highway (Finnish national road 12) bypassing the Lahti city centre was completed less than a year ago. Previously, trucks and passenger cars drove through downtown Lahti. New traffic calculations show that most of the heavy traffic has shifted from the road going through the city to the new bypass. Nearly half of passenger car drivers also choose the highway.
– The new bypass has probably already reduced noise, especially in the city centre. We will know for sure towards the end of the year when the results of the noise calculations become available, Johanna Saarola says.
Noise along the highway has been combated, for example, by placing it partly in a tunnel and inside the ground. In addition, noise barriers, banks and protection rails have been built along the bypass. In populated areas, the noise level along the bypass falls below Finnish standards. In Finland, the average noise level near dwellings may not exceed 55 decibels during the day and 50 decibels at night.
New noise study under way
During its Green Capital year, the City of Lahti intends to comprehensively survey the city’s noisy and quiet areas. The new study will be carried out using the traffic volumes from 2021 and will be completed by June 2022. The previous noise study was conducted in 2017 and survey of quiet areas in 2018.
According to EU regulations, the noise study must be updated every five years.
The results of the study affect, for example, land use (i.e. zoning and construction) in the municipality. The city’s noise prevention plan will be updated for the next five years based on the study.