M4 Junction 32 Coryton Interchange

This project involved:

• providing a dedicated route from the M4 westbound to the northbound A470.  
• construction of a new signalised junction on the A470 to allow for the motorway traffic to join the A470 and to negate the need to travel around the Coryton roundabout.

A review of the scheme has been completed, this involved reviewing the traffic model that was produced for the detailed design for the scheme and comparing it with the post opening queues and traffic flows.

The findings of the review have concluded that overall the scheme has been a success, inline with the original model results. The review has shown that the scheme has helped to improve the capacity of the junction, which experiences congestion and lengthy queuing at peak periods.  The dedicated lane has eased queuing and delays on the M4 westbound off slip, and so helped save on journey times and increased journey time reliability.  The scheme has also improved the local road network by providing improved access at the junctions onto the roundabout.  

Work was completed in August 2014 and the Minister for Economy, Science and Transport officially opened the road in September 2015.