The Highways Agency has launched a consultation on its plans to impose a mandatory 60mph speed limit on the M1 motorway between junction 28, near Matlock, and junction 35a, north of Rotherham, in place of the national speed limit.
The consultation document explains that this does not refer to the use of variable mandatory speed limits or the principle of managed motorways.
Separate consultations have been held on the implementation of variable mandatory speed limits on this section of the motorway.
This latest consultation exercise is open until 3 March 2014 and notes that most of this section of the motorway carries traffic in excess of the level for which the road was designed, causing congestion and delays.
The Highways Agency has developed proposals to implement managed motorways, ie all-lane running between junctions 28 and 31 and between junctions 32 and 35a, and to install variable mandatory speed limits between junctions 31 and 32.
While this is expected to increase motorway capacity and reduce congestion, the Agency has concerns about a number of nearby Air Quality Management Areas (AQMAs).
It notes that, for operation at the national speed limit, the much needed extra capacity and the increased traffic flows that these schemes will provide will also have adverse impacts on local air quality at AQMAs.
Assuming a favourable response to this request for comments, the Agency expects the 60mph speed limit to be operational by 2015.
Given the newer, cleaner vehicles coming into use in 2014 with the introduction of the new version of the Euro-type engines, however, and particularly the requirements of the Euro VI regulations (affecting HGVs), the proposed change will be reviewed to determine whether it is still needed as air quality improves.