Question to the Department for Transport:

To ask the Secretary of State for Transport, what estimate he has made of the average cost per mile to upgrade a motorway to a smart motorway.

Highways England has an improvement programme to create additional network capacity by utilising the motorway hard shoulder as an additional lane. This is known as the Smart Motorway Programme.

The cost depends on the scope and nature of each scheme and is heavily influenced by factors such as the number of junctions and the extent of work needed to existing structures.

Based on the actual or forecast actual cost of relevant schemes started over the past five years, the total cost ranges from £7.5-£8.8m per mile of additional network capacity (using a common price base of March 2015).