Study quantifies benefit in air quality from fixing potholes, clearing garbage in Delhi

Study by IIT Delhi shows fixing roads and clearing garbage dumps can reduce pollution by 15-26%.

Filling potholes, fixing unpaved roads, and clearing garbage dumps can potentially reduce particulate matter pollution from 15% to 26%, says a study by researchers at the Indian Institute of Technology, Delhi.

Though not peer-reviewed and relying on a limited sample, the analysis was an attempt at quantifying the merits of municipal-level actions on improving air quality.

While various studies have quantified the relative role of sources such as transport vehicles, power sources, factories, biomass burning, road dust to Delhi’s air quality, the focus has largely centred on managing coal plants or checking pollution from vehicles. The benefit from addressing sources of dust has not been quantified.

The study used data from the Dispersed Sources Program (DSP) that has been deployed in 12 urban local bodies with the Municipal Corporation of Delhi (MCD) being the local agency responsible for running the programme.

The DSP is an initiative by the non-profit Air Pollution Action Group (A-PAG) that has tied up with urban local bodies in Delhi-NCR. Affliates with A-PAG scour the city for instances of potholes, unpaved roads etc and take pictures. This is then sent to the official concerned, responsible for that ward, through a dedicated website and APAG tracks and sends automated reminders to the officials to fix the problem.

Researchers at IIT-Delhi, apprised of this, set up a study to examine if fixing these potholes or clearing out garbage dumps had an effect on air quality. Previous studies have shown that several of these sources — such as unpaved roads, garbage dumps and potholes — generate dust and therefore PM 10 and PM 2.5 particles.

For their study, the researchers chose three localities — Jahangirpuri, Rohini and Karol Bagh — and set up a network of sensors capable of detecting PM 2.5 concentrations. The measurements were made in a way that the detectors mapped changes in PM 2.5 levels before and after interventions were carried out. Because weather and wind alleviate air pollution, the measurements estimated the difference in PM 2.5 following these interventions, over and above the impact of changes that would anyway have occurred from daily changes in weather, said Sagnik Dey, Professor, Centre for Atmospheric Sciences, IIT Delhi, the lead scientist of the study.