Oxford City Council and Oxfordshire County Council have announced plans to introduce a new Low Emissions Zone (LEZ) for buses around Oxford.
The proposed LEZ, which follows consultation with local bus providers, will require buses to have engines of Euro 6 standard at minimum as the councils try to tackle air pollution around the city.
The proposals form part of the cityâ€™s plans for a Zero Emissions Zone (ZEZ) as the city looks to achieve zero transport emissions by 2035.
Councillor Tom Hayes, Oxford City Councilâ€™s cabinet member for Zero Carbon Oxford, said: â€˜This new Low Emission Zone will be a life-saver. Vehicles are polluting our air and making people sick.
â€˜This Council has to slash pollution levels in order to prevent ill health and stop early death, and the bus operators have a role to play.â€™
Transport is the most significant source of nitrogen dioxide (NOx) in Oxford, accounting for 75% of emissions, with 56% of this estimated to come from buses in the city centre.
Data from the cityâ€™s 74 air pollution monitoring stations in 2018 found that four locations in Oxford have NO2 levels above the legal limit, including St. Clements Street and High Street.
The new LEZ will apply to the city centre and main routes leading into it, expanding upon the area already covered by the cityâ€™s current Euro 5 Low Emissions Zone which was launched in 2014.
The councils are proposed to introduce the new LEZ in two stages, starting in December 2020 when almost all local buses that operate on the streets affected will need to be of Euro 6 standard.
Buses which serve stops more than 10km in a straight line from Carfax will be exempt from the LEZ until December 2022, by which time they too will be expected to comply.
Oxford City Council has already secured Â£2.3m from the Clean Bus Technology Fund to retrofit 115 buses to Euro 6 standard and will be introducing five electric buses in 2019.
The councils estimate that 89% of bus miles driven within the new LEZ will be Euro 6 by December 2020.
However, Oxfordâ€™s bus operators have warned that further investment will be required for them to meet the required standard in time and avoid knock-on effects on passengers.
Chris Coleman, managing director of the bus operator Stagecoach, said: â€˜While the majority of our buses will meet the LEZ requirements in 2020 & 2022, some investment will be needed to meet the requirements in full.
â€˜Unfortunately additional costs can make it more difficult to keep fares low but we will do our best to minimise any impact on our customers.â€™
Earlier this year Oxford City Council and Oxfordshire County Council published updated proposals for a Zero Emission Zone (ZEZ) to improve air quality in Oxford city centre.
The councilsâ€™ phased approach to the ZEZ will see emission restrictions on vehicles entering Oxford city centre increasing gradually between 2020 and 2035, by which time they hope the city centre will be largely transport emissions-free.