JAKARTA: Jakarta is once again relying on mist spraying to reduce air pollution in several areas across the capital, but critics have argued that spraying water does not address and may even exacerbate the persistent issue in the city.
The Jakarta Environment Agency has deployed two trucks equipped with “fog cannons” to pray 4,000 liters of mist to disperse small and hazardous particulates that pollute the city’s air.
The agency has been running the long-planned initiative since Sept 18, targeting crowded areas such as along the Jl. TB Simatupang in South Jakarta and Lapangan Banteng Park in Central Jakarta.
“Air pollution is a major challenge for Jakarta,” Jakarta Environment Agency head Asep Kuswanto said.
“By spraying water mist, we are trying to curb the concentration of pollutants, as well as reminding the public about the importance of keeping the air quality good.”
Jakarta has frequently found itself on the list of cities with the world’s worst air quality in recent years.
The level of observed PM2.5 fine particulates in Jakarta on Wednesday reached around 49 micrograms per cubic meter (µg/m3), according to data from Swiss technology company IQAir, around 10 times higher than the 5 µg/m3 that the World Health Organization (WHO) considers safe. The pollutant was observed much higher during the morning and evening rush hours.
Asep added the mist spraying was intended to particularly reduce the concentration of PM2.5, a fine particulate matter that is invisible to the naked eye and often linked to various lung and heart diseases as well as stroke and cancer.
Spraying roads, parks and other crowded spaces with water or mist is a known method applied in cities across the world to clean the air from coarse particles and visible dust. But several studies suggest spraying mist onto polluted roads has little effect in curbing PM2.5. E
ven though water mist can reduce coarse dust within a limited space or industrial area, its effectiveness varies, said Bondan Andriyanu of Greenpeace Indonesia’s climate and energy team.
He cited several previous studies that suggested spraying water may worsen the concentration of PM2.5.
In a study published in 2024 in the Atmospheric Chemistry and Physics journal, researchers found mist spraying using fog cannons could suppress road dust in Nanchang, Jiangxi province, China.
However, using the mist also led to an immediate 13-per cent increase in PM2.5 concentration because of the increased humidity caused by mist spraying that caused the fine particulates to pile up.
“This means the mist spraying is only a short-term emergency solution, not a cure to Jakarta’s air pollution crisis,” Bondan said.
He urged the city administration to root out the sources of pollutants, which mostly stem from coal-fired power plants and industrial areas surrounding Jakarta as well as internal combustion engines in vehicles on the city’s streets.
Similarly, Katherine Hasan, analyst from think tank the Centre for Research on Energy and Clean Air (CREA), raised concerns about the impact of fog cannons in tackling smaller polluting particles and other dangerous gases.
She suggested the government be more critical in addressing the sources of air pollution by focusing on intervention measures that have been proven effective, such as restricting high-emission vehicles, increasing public transportation ridership and promoting the use of renewable energy.
“The government needs to act now,” Katherine said.
“The longer the problem is left untreated, the higher the barriers that must be overcome.” - The Jakarta Post/ANN
