Smart Motorways

The new name for actively managed motorways

‘All lanes running’ motorways have variable speed limits, no hard shoulder, and emergency refuge areas every 2.5km

‘All lanes running’ motorways have variable speed limits, no hard shoulder, and emergency refuge areas every 2.5km

Blue signs and ‘M’ prefixes aside, for a little over 50 years the term ‘motorway’ for most people has meant a dual carriageway with a 70mph speed limit, hard shoulders on either side for the entire length and emergency telephones every 1.5km.

We got variable speed limits on the western side of the M25 as early as 1995 but things really started to change in 2006 when a stretch of the M42 became a fully flexible ‘controlled’ motorway - it has a hard shoulder which can be opened and closed, variable speed limits, lane control, overhead gantries, and emergency refuge areas.

In 2013 the Highways Agency coined a new term, ‘Smart’ Motorways, to describe a range of different designs of actively controlled motorway some of which have no hard shoulder at all.

Different types of Smart Motorway

Controlled motorway

A controlled motorway is one with multiple lanes, variable speed limits and a hard shoulder for use in emergencies only.  (e.g. western section of M25)

Hard shoulder running

Some sections of motorway have a variable speed limit and a hard shoulder that can be opened as a running lane at busy times. Overhead signs tell drivers when the hard shoulder may be used and when it must not.  (e.g. M42 J7-9, M4 J19-20, M5 J15-17)

All lanes running

This is the standard for all new ‘smart’ motorway schemes started from 2013 on.  ‘All lanes running’ motorways have variable speed limits, no hard shoulder, and emergency refuge areas every 2.5km. (e.g. M25 J23-27, M25 J5-6/7)

Highways Agency regional control centres use CCTV cameras and variable message signs to manage smart motorways. Depending on the type of motorway, speed restrictions can be set and lanes closed in the event of an incident or congestion.

Overhead and large nearside information signs are used to warn drivers about queuing traffic and speed limits as well as being used to close lanes and divert traffic in the event of an incident.

Highways Agency map showing smart motorway locations »

Don't ignore the red X

The most important feature of the new smart motorways is the Red X sign used to show when a lane is closed due to an incident or obstruction.

If a red X is displayed you must not proceed further in the lane indicated – driving in a red X lane is dangerous and can lead to prosecution.

Don't ignore the red X

A red X means lane closed

Breakdown advice

If you break down on a motorway without a hard shoulder you should try to use an emergency refuge area, motorway service area or leave at the next junction.

If this is not possible try and get the vehicle off the carriageway, if it is safe to do so.

If there is no choice but to stop in a live lane;

  • use hazard warning lights
  • if you are in the left hand lane and it is safe to do so, exit the vehicle via the left hand door and wait behind the barrier if possible.
  • if you cannot exit the vehicle, do not feel it is safe to do so or there is no other place of relative safety, stay in the vehicle. Keep your seat belt on and dial ‘999’.

What to do if you break down on a motorway with a hard shoulder »


(15 April 2014)