Question to the Department for Transport:
To ask the Secretary of State for Transport, for what reasons the M4 speed limit is 40mph near Junction 1 in both directions.
The 2002 Statutory Instrument set speed limits for sections of the M4 between J1 and 3 (various sections at 40mph, 50mph and 60mph). There is a recent SI that set the speed limit between J3 – J4 and this was to manage the air quality for this section so that it was compliant. The M4 between J3 -12 is a smart motorway and therefore the area between this stretch without a fixed speed limit is subject to a Variable Mandatory Speed Limit (VMSL).