Admitting that the first phase of the odd-even car rationing scheme did not lower pollution levels in the city “as much as expected,” Delhi chief minister Arvind Kejriwal said on Wednesday that the experiment significantly helped reduce traffic congestion. He added that the scheme could be enforced for a fortnight every month if the second phase beginning from April 15 is a success.

“Odd-even did lower pollution, but not as much as expected. However, it significantly reduced traffic congestion, the roads were cleared and people liked it very much,” he said in reply to a question by a SarvodayaBalikaVidyalaya student.

“The second phase of the odd-even scheme is very important. If it turns out to be successful, we are thinking of implementing it for 15 days every month,” MrKejriwal said at an event to administer oath to people involved in the implementation of the scheme.

MrKejriwal said a debate is going on whether the scheme had any effect on pollution during the trial in January and estimates vary. “Fortune magazine says it dropped by 13 per cent, others say it lowered by 55 per cent. Pollution did lower due to odd-even scheme,” MrKejriwal said and questioned reports claiming an “increase” in pollution. “I was watching an interview of a child who asked how could pollution increase when the number of vehicles on the roads of Delhi had reduced,” he said.

Claiming that the sale of petrol and diesel had gone down by 40 per cent during 15-day trial, MrKejriwal added it is “natural” that pollution lowered as less fuel was consumed.

The AAP government is also taking other measures to check air pollution, including introduction of luxury buses with increased frequency to popularise public transport and vacuum-cleaning of the roads. “In the next 2-3 months, we will ensure vacuum cleaning of over 1,000 km of roads.”

MrKejriwal also conceded that his government has not been able to find a solution to the problem of cars returning after dropping children to schools and going to pick up them.

One of the new exemptions is that vehicles ferrying children in school uniform will be exempted from the odd-even rule, but there are concerns about what will happen when the car is on its way back.

MrKejriwal suggested car-pooling with neighbours to avoid problems. “We gave it a lot of thought, but no solution could be found. It will cause some problems, but vehicles could be shared with neighbours,” he said. Mr Rai advised the students to take help of the government’s PoochhO Carpool app.

MrKejriwal cited his meeting with Union transport minister Nitin Gadkari on Tuesday, saying that completion of the Eastern and Western Peripheral Expressways will divert trucks from Delhi and improve air quality.

“The minister promised that the Eastern and Western Peripheral Expressways will be completed in next 400 days. This will improve situation of air pollution in Delhi as trucks will be diverted from entering the city.”

MrKejriwal also appealed to Prime Minister Narendra Modi and Union ministers to follow the odd-even scheme voluntarily. “I strongly believe that like the first phase in January, the second phase too will be successful,” he said.