Valasaravakkam worst hit by noise pollution in Chennai: IIT-M study

Chennai: High levels of traffic coupled with construction activities contribute to chronic noise pollution in the city, posing high public health implications, a study commissioned by the Tamil Nadu Pollution Control Board (TNPCB) revealed.The eight-month study, carried out by IIT Madras by setting up 60 low-cost sensors (four in each of the 15 zones), revealed that Valasaravakkam was a high-exposure area to noise pollution, consistently facing breaches of permissible decibel levels during day and night. The sensors measured data from 6am to 10pm (day) and 10pm to 6am on all days from March-Dec 2025. Throughout the period of study, the zone logged at least 10db (A) on average above permissible limits during the day and 25db(A) to 30db(A) during the night, highlighting a severe breach.
Ambattur (zone 7) was another area that logged breaches in noise levels, while Adyar (zone 13) and Manali (zone 2) had limited traffic volumes and commercial intensity, and subsequently lower pollution.The study came after the govt tied up with IIT Madras in Sept 2024 to map noise levels in cities with a population of over 1 million, beginning with Chennai. While the Central Pollution Control Board (CPCB) standards map noise levels by categorizing them as residential, industrial, silence and commercial zones, the study delved deeper, adding traffic and sensitive zones to better map the areas. Members associated with the study said that this was done to better represent the areas on the basis of the pollutants."The permissible limits for these zones are comparable with commercial and silence zones. One of the reasons we did this study was to identify the specific sources of noise and develop targeted plans to address noise pollution. Beyond commercial activity, there are multiple contributors to noise, especially traffic," Shiv Nagendra, project coordinator, said.TNPCB chairperson M Jayanthi said the study was intended to identify the high-prone areas, for which mitigation strategies could be worked upon. "The first step is identification. We have done that. We will also look to expand this study to other cities," she added.The study also highlights various strategies, including the use of sound-absorbing materials in walls, ceilings and facades, floor and wall insulation, and the promotion of electric vehicles and public transport, among others. "We did a study on mitigation strategies at IIT Madras too, since it is located next to the Cancer Institute (a silence zone). We suggested practical steps to contain noise within designated areas," Nagendra added.