The huge cost of gridlock on the M4

WALES’ motorway is brought almost to a standstill 30 times a day – costing the nation’s economy £165m, it has been revealed.

The South Wales Echo has obtained statistics showing the sheer scale of the disruption caused on a motorway now dealing with far more traffic than it was designed to cope with.

The figures from traffic service Inrix show on the stretch of the M4 in Wales, from Caldicot to Carmarthenshire, there were 10,809 traffic jams in the past 12 months.

That is an average of more than 900 a month or 30 every single day.

Earlier this month, a fatal crash caused the M4 to close for five hours, causing congestion to hit nearby town and city centres.

Inrix uses sophisticated calculations based on the volume of cars caught up and the extent of the delays to calculate the effect on the economy of lost time and delays.

It has calculated that the worst month for economic impact was during the summer holidays in August this year, when the economy lost £18m because of traffic jams, and that in total over the last year it has cost a whopping £165,369,791.

It revealed that junction 38, in Margam, had the most traffic jams, with junction 42 – Briton Ferry – coming second.

The next busiest junctions were 28 and 29 between Cardiff and Newport.

The data covers the 12 months from September 2016 to August this year, and revealed July and November saw the highest incidence of traf- fic jams on the Welsh section of the M4 but the ones in April and August were the worst for impact – being 33% more severe than the average jam.

Inrix said it calculated the economic impact by assessing “the value of wasted time, fuel and unnecessary carbon emissions as a result of the delay imposed on drivers by these traffic jams”.

Transport experts say the M4 sees so many traffic jams because it is used not only for long-distance trips but also, particularly around Newport, for local journeys.

Cardiff University professor Andrew Potter said it was the “only decent road going east to west”.

“The alternatives either route through urban areas like the A48, or don’t really go in the right direction, such as the Heads of the Valleys,” he said.

Professor Stuart Cole, of the University of South Wales, said the number of cities in a short stretch contributed to the problems. He said: “This stretch of road is the link between Bristol, Newport, Cardiff and Swansea – four big cities. Cars go towards the motorway a bit like a magnet as it’s perceived as being faster than other routes – and it is, generally.

“The M4 is seen by everyone as a big, useful road, and people expect they can do good time on it. Between 4.30pm and 6pm, it’s very, very busy because everybody’s going home. But whenever there’s an accident, it just cannot cope.”

According to the Department for Transport, in 2013 74,000 motorists used the M4 in Wales every day, and in 2014 that number rose to 76,000, which at the time was the “busiest year” since records began in 2002. But Prof Cole said numbers at present are more like between 80,000 and 90,000.

When that volume of cars is diverted onto the surrounding roads, gridlock to the entire region.

Recently, part of the M4 was closed for more than five hours after a serious crash, and it was announced last Wednesday that a 70-year-old man from Swansea died after a collision involving a Ford Mondeo and Mercedes Sprinter close to junction 23A at Magor. Delays hit a huge area, including clogging up traffic in Newport city centre and its surrounding towns.

Steve Brooks, national director of transport charity Sustrans Cymru, said: “This latest crash is another sad reminder of how vulnerable south east Wales is to problems on the M4. The road is notorious for congestion, gridlock and serious road traffic accidents.” it brings