The impact of delays during construction of the current M6 Junctions 2 to 4 and Junctions 13 to 15 smart motorway schemes was assessed as part of the economic appraisal undertaken prior to the start of construction. This took into account various factors including the impact of the construction programme in full, lane availability and also the effect of limiting traffic speed to 50mph. This assessment gave an estimated value of £80 million for motorist’s journey time lost during construction.
The economic appraisal also forecast that the completed schemes would give a journey time gain of £802 million to motorists.
In July 2018, Highways England announced its intention to test whether 60mph speed limits in roadworks could be used more often. That work is ongoing, and it is anticipated that the benefits will include improved journey times for motorists.