Drivers of heavily polluting vehicles could have to pay on some of Wales’s busiest roads under a new law.
The Welsh government says it has no plans to charge drivers, and it will only happen if 50mph zones fail to reduce emissions.
Newport’s section of the M4 and a part of the A470 at Pontypridd have been considered as potential clean air zones if lower speed limits do not work.
Plaid Cymru and the Conservatives said it was a “step forward” but “overdue”.
The charging powers are contained in a long-awaited bill that also paves the way towards new national targets on cutting pollution.
Other plans include steeper fines for drivers who leave their car engines idling, especially when parked outside schools.
Councils will get new powers to enforce smoke control areas, where there are restrictions on what fuels can be burned.
To tackle noise pollution, ministers will have to produce a strategy that would also protect natural sounds, such as birdsong.
But the government is not proposing to ban wood-burning stoves in the legislation, entitled the Environment (Air Quality and Soundscapes) Bill.
At present, the Welsh government can only introduce clean air charges on roads in limited circumstances, for example where there are bridges or tunnels of at least 600m.
Nitrogen dioxide
That would change under the new law, with ministers able to create low emission zones anywhere on the trunk road network, which includes the M4.
Speed limits of 50mph have been introduced on five sections of motorway and A roads to reduce the amount of nitrogen dioxide released from vehicle exhausts.
They include the M4 between junctions 25 and 26 and the Upper Boat to Pontypridd stretch of the A470 in Rhondda Cynon Taf.
Government documents say clean air zones will only be considered in those two locations “should the reduced speed limits fail to ensure sustained, long-term compliance”.
The law, which will need to be passed by the Senedd, would not apply in towns and cities, where local councils are in charge of the roads.
But the government said it will also let councils introduce their own emissions charges, as has happened in some English cities.
Parents at the school gates of Maesglas Primary School in Newport had mixed feelings about the possibility of a charge.
Deb Loganathan, who walks her daughter to and from school, said it could be a good idea.
Increased cost of living
“We’ve got to prioritise the environment, I don’t drive myself, so that makes me slightly biased. But anything that will increase the reason for people to get electric vehicles or lower polluting vehicles then yes, definitely.”
Katrina Rafferty, who was also picking up her daughter, felt that because of the increasing cost of living there should not be a charge.
“People can’t afford to live as it is,” she said. “If you want to be able to go to town you shouldn’t have to pay really”
“It’s just putting more money on top of money that people haven’t got.”
Climate Change Minister Julie James said: “By introducing this bill, our ambition is to further improve air quality and soundscapes by bringing forward new measures to reduce the impacts of air and noise pollution on human health, biodiversity and the natural environment.”
The bill was welcomed by campaigners.
Joseph Carter, of Asthma and Lung UK, said: “Air pollution is one of the most pressing public health issues we face, and it is especially damaging to our children’s developing lungs.”
Friends of the Earth Cymru director Haf Elgar said: “Air pollution is not only a public health issue, but also a social justice issue and an environmental issue.”
Plaid Cymru climate change spokesperson Delyth Jewell called the bill a “step forward”.
But she added: “This bill is painfully overdue and there are still questions about its scope and how exactly it’ll be enforced.”
The Welsh Conservatives’ Janet Finch-Saunders said the party welcomed the step towards improving air quality in Wales, adding that legislation in this area was “long overdue”.
“However, it is clear from the wording of this bill, that this is barely even a first step to introducing a comprehensive Clean Air Act, of the like the Welsh Conservatives have been calling for, for years.
“The Labour Government need to step up their game and as is the case with all legislation, the devil will be in the detail. Colleagues and I will be looking to see whether this bill goes far enough to address the longstanding issues we face here in Wales.”