Leuven tries to tackle party noise with smart tech

City officials found that simple messages about respecting residents’ sleep were most effective if coupled with the right presentation

This week, the municipality of Leuven announced the results of several pilot projects aiming to reduce night noise in the city. Authorities installed noise measuring devices and employed different measures to try and find out the most effective one.

According to the data, the projectors with messages of empathy had the biggest impact, although other digital and smart interventions have also proven useful. Some projects have been able to reduce noise by up to 30% without police intervention – a very promising result for local authorities.

Leuven has a bit of a party reputation, with young people having a good time late into the night. However, it also has a lot of working people, who have to be fresh and perky in the morning and oftentimes, these two groups collide. To solve the issue, the city tried out several projects, using light, noise metres, stickers on the ground, projectors and automated dimmers.

Measuring the noise

The first step to reducing street noise at night for Leuven authorities was to identify sources and develop a way to measure the results of different initiatives. This was done through the use of noise-measuring devices spread throughout residential areas between August 2021 and November 2022.

The devices logged sounds above 70 decibels and were able to distinguish between sources, like residual noise, the human voice and cars. According to the data, the noisiest nights were on Wednesday, Thursday and Friday.

Moreover, the top source of the noise was by far cars, followed by residual noises while the human voice, instances of laughing or shouting, came in third. The noisiest month was October 2022, followed by March 2022, when many Covid-measures were lifted.

Different ways to tackle noise

Despite the fact that cars seem to be the biggest producers of noise, the measures the city used were focused on reducing human noise, such as shouting, laughing and partying in the streets.

The most effective measure proved to be a light projection on St. Michael's Church. The projection lit the ground and simply asked passers-by to respect the sleeping residents and leave the party behind. This resulted in a 30% reduction in the affected area while it was operational, three weeks in the summer and October and November 2022.

Additionally, the system proved to be most effective up until around 2 AM, after which the effects were barely noticeable.

This measure was pitted against the same idea, asking people to please respect their sleeping neighbours. However, instead of a light projector, the competing project tried to achieve this with stickers on the ground – which proved very ineffective.

Another measure was to dim or increase the intensity of streetlights based on noise levels. According to the city, this method also had some effect, however, the data remains inconclusive, according to the Alderman of Student Affairs Thomas Van Oppens.