M4 Port Talbot NO2 Falls Below Legal Limit After 50mph Curbs

3 articles · Updated · bbc.co.uk · Jul 21

Official data shows nitrogen dioxide on the M4 through Port Talbot has dropped below the legal threshold after a 50mph limit was imposed on the elevated motorway.
The restriction followed court action over illegal NO2 levels; analysis cited in the report says the speed cap delivered the biggest immediate improvement, though cleaner vehicles and more home working also helped.
Wales spent more than £5.6 million in 2018 creating five 50mph zones, including Port Talbot, adding pollution monitors, speed cameras and signs.
About 75,000 vehicles use the 4.25-mile stretch daily, and residents living beneath the 1966 motorway said the lower limit has also reduced traffic noise.
The result highlights how a road once built for speed and congestion relief at a cost of more than £5 million is now managed to meet modern air-quality rules.