A NEW 50mph speed limit will come into operation on Monday, from junctions 24-28 (Coldra-Tredegar Park) of the M4 around Newport.

The restriction is designed to improve safety and flow of traffic on a particularly busy stretch of the motorway, and will remain until summer 2010, when a new variable speed limit system is introduced.

Congestion, work to replace the central reservation safety fence, and the ongoing widening improvements between junctions 29 and 30 are the reasons why a 50mph limit is being introduced.

The length of road affected by this speed limit will be reduced when the widening works are completed, currently scheduled to be December this year.

Work has started on the replacement of the central reserve steel safety fence with a concrete barrier that meets current standards. Concrete barriers are virtually maintenance free and much more effective at preventing large vehicles from crossing over into oncoming traffic in the event of an accident.

Such incidents have increased recently and have caused serious accidents and delays to motorists.

From summer 2010, electronic signs on overhead gantries will allow the speed limit to be varied, to control motorway traffic to suit prevailing conditions.