WALES IS considering junction closures at key points on the M4 motorway around Newport to relieve pressure on the notorious Brynglas tunnel bottleneck.
The Welsh Assembly has asked Capita Gwent Consultancy to investigate whether selected junction closure would stop local traffic using the motorway.
This could relieve pressure on the tunnel and improve long distance journey times.
The pair of 350m long twin bore tunnels is used by 80,000 vehicles a day. It has become a traffic bottleneck over the years because the motorway narrows to two lane dual carriageway as it passes through.
Studies have shown that the Brynglas section of the M4 through Newport is heavily used by local traffic.
As well as junction closures Capita Gwent is also examining the impact of imposing variable speed limits, as used on sections of the M25, or cutting speed limits permanently.
The firm is looking at introducing a strategic park and ride scheme between Newport and Cardiff, and introducing high occupancy vehicle lanes.
Scope for junction improvements is also being considered.
The consultant makes its final recommendations to the Welsh Assembly next week.
The Welsh Assembly is keen to assess the options for improving the capacity of the existing road before looking again at how to increase capacity on the M4.
Previous studies have ruled out online widening as technically impossible, and in 2002 the Welsh Assembly rejected a £400M improvement scheme running south of Newport for environmental and cost reasons.
A new southern link, the Newport Southern Distributor Road (SDR), opens later this year, but it is not designed to carry through traffic and does not have grade separated junctions.