The Delhi government launched the odd-even car rationing scheme on Monday as a desperate measure to curb spiralling pollution levels with the city’s average air quality index remaining in the severe zone for at least four days even as experts maintained that the measure may only have a limited impact and the Opposition slammed the government saying that “things are going out of control”.

The plan, first implemented in Delhi in 2016 and repeated in 2007 and 2019, has been a matter of debate with no comprehensive study backing the step in its efficacy to curb vehicular pollution. The odd-even scheme is part of the restrictions mandated under Grap-4 when air quality index reaches severe+plus levels (AQI value of 450+).
Announcing that the scheme will be implemented between November 13 and 20 — a day after Diwali on November 12 — Delhi environment minister Gopal Rai said data will be reviewed at the end of week, along with pollution levels during the time when the curb will be imposed, to assess the need for continuation of the scheme.
A study by a team of scientists from IIT-Delhi, IIT-Kanpur, IITM-Pune, CSIR and the TERI in 2016 showed the odd-even scheme had a limited impact of 2-3% on pollution caused by vehicles.
Another study by Delhi Technological University (DTU) on the 2016 implementation of the scheme found that the concentration of PM2.5 and PM10 levels dropped, but only partially. According to the study, an average reduction of 5.73% in PM2.5 levels and 4.70% in PM10 levels was seen across three roads assessed by the authors.
While the finer operational details of quantum of fines, restriction timings and exemptions will be decided in a meeting on Tuesday, experts were divided over the efficacy of the scheme and the number of exemptions.
In the previous editions, the exempted categories included two-wheelers, EVs, vehicles driven by women, children aged up to 12 years, taxis, physically disabled people, VIPs, and emergency and defence vehicles.
Sunil Dahiya, analyst at the Centre for Research on Energy and Clean Air (CREA), argued that the move is needed immediately and not next week. “We don’t know what the air quality will be then, but we do know that Delhi’s air has been severe for five straight days and such emergency measures are needed now and not later,” he said.
Anshuman Tiwari, 37, who commutes between Noida and Barakhamba Road, said the exercise is futile, until more polluting vehicle segments such as two-wheelers were targeted. “It reduces congestion and travel time, but since I had an even-numbered car, commuting on odd-days was extremely difficult as cabs would overcharge. As long as a car has a PUC certificate, it should be allowed to ply,” he said.
Shah Mohammad Faisal, who works in multinational company having its office in Gurugram, said no such scheme could make a difference until the public transport system was strengthened. “A lot of people in Delhi go to Noida and Gurugram for their job, how are they supposed to go about their daily commute when nearly half of the vehicles would be forced to stay off roads. The government must have some scientific data to back the efficacy of steps such as odd-even. It’s a disruptive and cosmetic move at best,” he said.
The Delhi Bharatiya Janata Party (BJP) opposed the move calling it a “punishment for people of Delhi”. Delhi BJP president Virendra Sachdeva said be it the odd-even scheme or the ongoing red light on, engine off scheme both are not backed by scientific data. “In the past when this scheme was implemented, Delhi has never experienced any qualitative improvement in air. By bringing the odd-even scheme, the government is punishing Delhiites for its own failure to curb pollution.”
Delhi Congress chief Arvinder Singh Lovely said, “Things are out of government control and now they are taking temporary measures for curbing pollution. We support the measures taken by the government, but we appeal to them to go beyond temporary measures in these two months. They should improve roads, strengthen the public transport system and plan for curbing local pollution sources. There should be long-term plan to mitigate pollution levels at every hot spot.”
