Smart motorways
Smart motorways were introduced to increase motorway capacity without the disruption, cost and environmental impact of widening roads. Using technology such as sensors, CCTV cameras and variable speed limits, they are designed to improve traffic flow, reduce congestion and respond quickly to incidents. Around 25% of England's motorway network is now made up of smart motorways.
What are smart motorways?
Smart motorways use a range of technologies to manage traffic and improve journey reliability. These include:
- Variable speed limits displayed on overhead gantries
- CCTV and traffic monitoring systems
- Electronic signs that provide information and warnings
- Lane management systems that open or close lanes when required
- Stopped Vehicle Detection (SVD) technology on many routes to identify stationary vehicles quickly
The objective is to make better use of existing road space while helping reduce congestion and improve traffic flow.
Types of smart motorway
Dynamic Hard Shoulder Running (DHS)
On these motorways, the hard shoulder can be opened as a traffic lane during busy periods.
- Identified by a solid white line separating the hard shoulder from the carriageway
- The hard shoulder must only be used when overhead signs indicate that it is open
- If no sign indicates that it is available, the hard shoulder should only be used in an emergency
All Lane Running (ALR)
All Lane Running motorways permanently use the former hard shoulder as a live traffic lane.
- All lanes are marked with broken white lines
- Emergency Refuge Areas provide places of relative safety for broken-down vehicles
- Lanes can be closed using overhead signs when incidents occur
Controlled Motorways
Controlled motorways operate with variable speed limits while retaining a traditional hard shoulder.
- Three or more running lanes
- Variable speed limits displayed on gantry signs
- Hard shoulder remains available for emergencies only
The future of smart motorways
In April 2023, the Government announced that all planned new smart motorway schemes would be removed from road-building plans due to financial pressures and a lack of public confidence. Fourteen planned schemes were cancelled, although work continues on projects that were already substantially complete.
However, investment continues in improving the safety of existing smart motorways. National Highways is investing £900 million in measures including:
- Stopped Vehicle Detection systems across the network
- More frequent emergency refuge areas
- Improved visibility of refuge areas
- Additional signage showing the distance to the next refuge area
- Better enforcement of Red X lane closures
- Public awareness campaigns about safe smart motorway use
How to drive safely on a smart motorway
Driving on a smart motorway is similar to driving on any other motorway.
Follow speed limits
Always obey the speed displayed on gantry signs. Variable speed limits are legally enforceable and are often supported by speed cameras.
Use the correct lane
- Keep left unless overtaking
- Return to the left-hand lane when it is safe to do so
- Follow lane closure instructions immediately
Watch for overhead signs
Electronic signs provide important information about:
- Congestion ahead
- Speed limits
- Closed lanes
- Incidents and roadworks
Understanding the red X sign
A Red X displayed above a lane means the lane is closed.
If you see a red X:
- Leave the lane as soon as it is safe to do so
- Do not continue driving in the closed lane
- Follow any diversion or lane guidance displayed on overhead signs
Why are lanes closed?
A lane may be closed because of:
- A collision
- A broken-down vehicle
- Road workers
- Debris or an obstruction
- A pedestrian or animal on the carriageway
Ignoring a Red X is dangerous and illegal. Drivers can receive a £100 fixed penalty notice and three penalty points. Automatic enforcement cameras are now used on parts of the network.
What to do if you break down
If your vehicle can still be driven
- Leave the motorway at the next junction if possible.
- If not, pull into the nearest emergency refuge area or hard shoulder where available.
- Switch on your hazard warning lights.
If you reach an emergency refuge area
- Exit your vehicle in the side furthest from the traffic, and ensure any passengers do the same
- Use the emergency telephone where available
- Contact your breakdown provider
- Follow instructions from National Highways
- Get behind the safety barrier where there is one while you wait for help
- Do not rejoin traffic until it is safe to do so and you have received appropriate guidance
If you cannot leave a live lane
- Keep your seatbelt fastened
- Turn on hazard warning lights
- Call 999 immediately. Alternatively, press your SOS button if your vehicle has one and ask for the police
- Tell the operator that you have broken down in a live lane on a motorway and provide your location if possible
Never:
- Place a warning triangle on a motorway
- Attempt roadside repairs in live traffic conditions
- Put yourself at risk by standing near moving traffic
Are smart motorways safe?
Motorways remain among the safest roads in Great Britain and must be shown to be at least as safe as the conventional motorways they replace.
Research indicates that:
- Smart motorways have lower rates of people killed or seriously injured than conventional motorways
- Risks involving collisions between moving vehicles are generally reduced
- The risk associated with vehicles stopping in a live lane is increased
- Emergency refuge areas provide a safer place to stop
Evidence also suggests that while different motorway types have different risks, smart motorways continue to perform as safely as, or safer than, conventional motorways when casualty-based measures are considered.