I AM appalled by the potential environmental impact and £830 million cost of building a new relief road to the south of Newport.

There is already a dual carriageway, the Southern Distributor Road, along which serious congestion is rare, though the stretch between the Statistics Office and Tredegar House roundabouts could usefully be widened at a much more modest cost.

Surely an alert system could be designed to enable westbound congestion at Brynglas Tunnels to trigger advice on motorway signs before the Coldra, saying: “Congestion ahead - through traffic may exit jctn 24 to rejoin jctn 28”.

Dr Miles C Allison, Usk