A simple way to ease congestion on our roads

sir – “Smart” traffic lights, which stay green for late-running buses (report, March 6), are just one change that could reduce congestion, especially in London.

There are currently many traffic lights that stay green only for about eight seconds. This allows four or five vehicles to pass at most, as it takes three seconds for the first car to get going (and longer if the vehicle is a heavy lorry).

Extending the green phase by between six and nine seconds would make a big difference to traffic congestion.

Edward Reeve

London SW1

A traffic light with the green and amber lenses missing in Kingston upon Thames, Surrey