The jury might still be out about the impact of the first phase of odd-even in bringing down pollution but the Delhi government’s road rationing definitely managed to reduce traffic on some of Delhi’s busiest stretches.
The odd-even policy was implemented by the Delhi government for the first time between January 1 and January 15 this year to clean the air of the city, which has been tagged as the most polluted by the WHO.
The Delhi Pollution Control Committee (DPCC) claimed that pollution in the city came down by 50 per cent during the first phase.
The DPCC’s results were collected by mobile vans in 200 locations that collected 20 minute data of the air quality. However, the readings taken by the agency during the odd-even scheme were at random spots and were compared with the city’s average in December.
Hindustan Times had compared the data provided by DPCC on December and January and found that there was a very marginal drop in pollution levels during the first week of the odd-even restrictions.
The Energy and Resources Institute (TERI) said there was a marginal drop in pollution levels during the odd-even scheme.
According to TERI experts, the main drop in pollution was because of high wind speed and low humidity in the second week. It said the number of cars on the road reduced by 21% during the first fortnight of 2016.
A webportal IndiaSpend, however, claimed that air-pollution levels in the city went up by 15% during the 15-day period when the odd-even plan was in place.
Another impact assessment done using satellite-based aerosol optical depth (AOD) technique to analyse air pollution levels found that the air quality in the city improved during the odd-even scheme. Naresh Kumar, a researcher at Miami University, did the analysis. The pollution levels in outer limits of the city and neighbouring towns, however, went up.
The more visible impact of the road rationing scheme was thinning of traffic and smoother traffic flow.
According to a study conducted by Central Road Research Institute (CRRI), there was a significant dip in traffic volume. The overall traffic volume saw a dip of 19.4% on odd days and 16.6% on even days on the Delhi-Mathura Road during the course of the study.
Another study by IIT Delhi stated that vehicle speeds had increased 11am onwards.Car-flow rates per hour on different roads decreased by 7-9%.