Opposition groups in Winchester are calling for the council to tackle city centre pollution, after it was found to be amongst the worst in Hampshire.
But the council has launch a public consultation on an Air Quality Action Plan (AQAP) which aims to reduce emissions.
Cllr Jan Warwick, portfolio holder for environment, said that the actions put in place by the council were starting to have an effect.
She said: “For the first time in 2016 there was no breach of statutory emissions levels in St. George’s Street in the city centre.”
The councillor said that the city council, whilst “delighted” with the improvements to air quality, was not complacent.
“With the AQAP we are making air quality considerations an integral part of the planning process.”
Winchester Action on Climate Change (WinACC) says it is pleased with the AQAP but worry that not enough is being done.
Chris Holloway, from WinACC, said: “The actions set out in the plan probably won’t be enough to reduce air pollution to get within legal limits by 2020, the government deadline.”