What is a Smart Motorway and How Does it Work?

Smart motorways are an advanced form of traffic technology which have been adopted in some countries around the world to improve safety, reduce congestion and maximize efficiency on roads. This article provides insight into what a smart motorway is, how it works, its benefits, types and features, the differences with traditional highways, the impact on drivers, and more.

Through this exploration of smart motorways, readers will get a better understanding of this revolutionary technology and the opportunities it brings.

What is a Smart Motorway?

Smart motorways are the modern marvels of the motorway network in England, using advanced technology to help traffic flow like a well-oiled machine. Unlike traditional motorways, they use variable speed limits, cameras and sensors to monitor the movement of vehicles and alert drivers if any are stationary.

Dynamic Hard Shoulder. Running is one type of smart motorway – it’s like adding an extra lane during busy periods by activating the hard shoulder. All Lane Running is another type where there’s no hard shoulder at all – every lane can be used by drivers. The third kind is Controlled Motorways which have both variable speed limits and a permanent hard shoulder.

Smart motorways don’t require building additional roads or widening existing ones; instead they rely on modern tech such as CCTV cameras and sensors to keep an eye on traffic and detect any incidents that may occur. This allows for national speed limit signs overhead or mandatory speeds enforced with solid white lines along the road surface.

The M42 was the first trial back in 2006, since then feedback has been gathered, lessons learned and improvements made so that now around 10% of England’s motorway network consists of current smart motorways with £900 million being invested in schemes from J16 to J13, J2 to J4, J13 to J15, and J10 to J12 respectively.

Smart motorways employ extensive technology including cameras adapting speed limits according to conditions; sensors detecting stationary vehicles; electronic signs displaying national speed limit information – all helping keep drivers safe while reducing congestion for improved journey times too! Despite this, some people remain concerned about their safety when travelling on strategic roads, especially those featuring Smart Motorways.

Types of Smart Motorways

Smart motorways are variable speed limit enabled motorways that use technology to improve traffic flow and reduce congestion. Smart motorways are divided into three types of schemes: Dynamic Hard Shoulder Running, All Lane Running and Controlled Motorways. Each type of scheme has a unique set of rules and guidelines. The enhancements on technology-enabled sections of motorways include hard shoulder opening/conversion, variable speed limits, and signs.

The difference between All Lane Running and Dynamic Smart Motorways is that All Lane Running involves the hard shoulder being permanently converted to an inside lane, while in Dynamic Smart Motorways, the hard shoulder is used by moving traffic at certain times. Overhead signs indicating whether the hard shoulder is open to traffic, as well as mandatory speed limits, are displayed on overhead gantries on these motorways.

Drivers are allowed to use the hard shoulder on certain occasions. These include during an emergency or when they are instructed to do so by police officers, Highways England traffic officers, or signs.

Dynamic Hard Shoulder Running

Dynamic Hard Shoulder Running schemes involve the hard shoulder being converted into a normal running lane during certain periods, such as busy periods, to improve traffic flow and reduce congestion. The hard shoulder is differentiated from the normal carriageway by a solid white line.

The former hard shoulder lane is marked with broken white lines to distinguish it from the normal lane. The hard shoulder is managed dynamically and can be opened and closed during peak periods.

All Lane Running

All Lane Running motorways involve the hard shoulder being permanently converted to an inside lane. Safety concerns have been raised about this scheme. MPs have suggested that the benefits of All Lane Running motorways do not outweigh the safety risks associated with permanently removing the hard shoulder.

When driving on an All Lane Running motorway, drivers must keep to the normal lane and should not cross the broken white lines marking the former hard shoulder lane. The speed limits shown on overhead signs apply to all lanes on the motorway, including the former hard shoulder lane.

If there are any live lane breakdowns on the motorway, the motorway must be immediately closed and traffic diverted by National Highways.

Controlled Motorway

Controlled Motorway schemes – what are they? They involve the use of CCTV cameras to monitor traffic flow and variable speed limits to reduce congestion. Plus, extra lane closures and traffic officers based on the motorway manage traffic flow. But what safety considerations should drivers be aware of? Well, you need to reduce speed limits during busy periods and ensure that the national speed limit applies when the hard shoulder is in use. Don’t forget hazard warning lights and speed limit displayed on overhead gantries! And if there’s a lane closure? One or more lanes will close with the left hand lane becoming a running lane. Mandatory speed limits exist for one reason: reducing congestion & improving traffic flow.

Benefits of Smart Motorways

The introduction of smart motorways has a number of benefits for drivers and the economy. Smart motorways are designed to improve journey times and reduce congestion. By actively managing traffic flows, smart motorways can help minimize delays on the motorway network. With the use of variable speed limits and extra lanes, drivers can expect fewer traffic jams and more reliable journey times.

Smart motorways also use vehicle detection equipment installed in or adjacent to the motorway at strategic locations, linked to a Motorway Incident Detection and Automatic Signalling (MIDAS) system. This allows for the monitoring of traffic conditions and the implementation of variable speed limits or emergency refuge areas when required.

The economic benefits of smart motorways are also clear. Smart motorway technology is used to optimize the motorway network, providing much needed capacity on the busiest motorways. The Department for Transport analysed figures between 2015 and 2018 and found that existing smart motorways are reducing journey times by up to 15 minutes. This helps the economy by decreasing delays and increasing productivity.

Additionally, smart motorways have environmental benefits. The introduction of variable speed limits has resulted in reduced emissions from stationary/slow-moving vehicles. Furthermore, the use of modern technology and the avoidance of building additional lanes has helped to minimize environmental impact, cost and time to construct.

Stopped Vehicle Detection (SVD) technologies are also being used to improve safety on smart motorways. These camera-based systems automatically detect stationary vehicles and communicate this information to control rooms. The implementation of Intelligent Radar Technology for detecting stationary vehicles is 16 minutes faster than SVD cameras. This allows for greater opportunities for intervention and quicker response times.

In addition, the increase of concrete central reservation barriers and the use of a queue protection algorithm provides further safety interventions. The implementation of these technologies helps to reduce the number of accidents on smart motorways, with data suggesting that death tolls on smart motorways are lower than conventional motorways.

In conclusion, smart motorways provide a range of benefits for drivers, the economy and the environment. Improved journey times, reduced congestion and emissions, efficient motorway network and improved safety are just some of the advantages of using smart motorways. With the introduction of more and more smart motorways, the strategic road network of the UK is only set to benefit.

Speed Limits For Different Vehicles

In the United Kingdom, speed limits are designed to regulate traffic flow and ensure the safety of all road users, including drivers of cars, vans, minibuses, and trucks. These limits vary depending on the type of road and the class of vehicle being driven, as each type of vehicle possesses different handling characteristics and potential risks. It is crucial for drivers to be aware of the appropriate speed limits for their specific vehicle to maintain safe and responsible driving behaviour.

For cars and motorcycles, the standard speed limits in the UK are set at 30 mph (48 km/h) in built-up urban areas, 60 mph (97 km/h) on single carriageways, and 70 mph (113 km/h) on dual carriageways and motorways. Speed limits for vans, including those towing trailers or caravans, have a slightly lower speed limit of 30 mph (48 km/h) in built-up urban areas, 50 mph (80 km/h) on single carriageways, and 60 mph (97 km/h) on dual carriageways and motorways. Minibuses, defined as vehicles with a seating capacity between 9 and 16 passengers, are also subject to these speed limits.

Trucks, or lorries as they are commonly known in the UK, have different speed limits depending on their maximum laden weight. For trucks weighing up to 7.5 tonnes, the speed limits are 30 mph (48 km/h) in built-up urban areas, 50 mph (80 km/h) on single carriageways, and 60 mph (97 km/h) on dual carriageways. On motorways, these trucks can travel at 70 mph (113 km/h) if they have a speed limiter installed. For trucks over 7.5 tonnes, the speed limits are 30 mph (48 km/h) in built-up urban areas, 40 mph (64 km/h) on single carriageways, 50 mph (80 km/h) on dual carriageways, and 60 mph (97 km/h) on motorways. It is important to note that these limits are subject to change, so drivers should always be vigilant and adhere to any posted signs indicating the appropriate speed for their vehicle.

Safety Considerations

With the introduction of smart motorways, additional safety measures have been put in place to ensure the safety of drivers. Emergency refuge areas have been increased along with the use of Stopped Vehicles Technology (SVT). SVT detects stopped vehicles on the motorway and activates the red X sign to alert other road users. Offenders who flout the rules on a smart motorway can be fined up to £2,500. It is important to be aware of the speed limits and follow lane closures when they are in place. It is also essential to know how to exit the vehicle safely in an emergency. Drivers should always exit the vehicle from the nearside (left hand) door, provided it is safe. If there is a safety barrier present, they should wait behind the barrier.

Critics have raised safety concerns about the hard shoulder being used as an extra lane. As the hard shoulder is narrower than a regular lane, there is an increased risk of crashes. Emergency vehicles also face longer journey times when responding to a crash on a smart motorway with the hard shoulder used as a lane. In response to public safety concerns, the Department for Transport commissioned a report by the Transport Committee in January 2022. They accepted the findings of the report and have followed recommendations to reduce the risks associated with smart motorway driving. This includes ensuring that the national speed limit applies to all lanes, and that safety barriers are installed between the hard shoulder and regular lanes.

To ensure safety on a smart motorway, drivers must ensure that their vehicle is safe and roadworthy before setting off. This includes checking the engine, brakes, tyres and fuel levels. It is also recommended that drivers keep items such as food, water, first aid kit, torch, jump leads, and phone chargers in the car if they are undertaking a long journey.

The RAC (Royal Automobile Club) has called for urgent changes to reduce the risks related to breaking down on motorways. They have asked for more emergency refuge areas to be installed along the motorway and for Stopped Vehicles Technology to be used in all lanes, not just the hard shoulder.

By following the rules and taking the necessary safety precautions, drivers can help reduce the risks associated with driving on smart motorways. It is important to adhere to the speed limits, stay alert, and drive with caution at all times.

How to Drive on a Smart Motorway

Smart motorways are a relatively new concept in the UK, and so it is important to understand the rules that apply to a particular smart motorway location at any given time. All drivers must adhere to the speed limits that are displayed on the overhead gantries, as well as any other instructions that are given. When overtaking on a smart motorway, drivers should keep left and avoid driving in a lane closed by a red X sign. Driving in a lane closed by a red X sign is against the law and can result in a fine of up to £100 and three points on your licence, or more severe penalties or a court appearance.

The overhead gantry signals will also display any mandatory variable speed limits, and drivers must be aware of these and adjust their speed accordingly. Variable speed limits are enforced by speed cameras, and drivers have a lag of 10 seconds between when the speed limit is changed and when the cameras will begin to enforce it, so it is important to be aware of this and adjust your speed quickly. Failure to obey the variable speed limits can result in a fine of up to £2,500.

Red X

A red X sign is like a stoplight on the motorway – it tells you when to slow down and take caution. Disobeying this warning can result in hefty fines, points on your licence, or even court appearances. Highways England’s process of closing lanes with red X signs is backed up by Traffic Officers and police officers who are present at the scene. The symbols can be seen on overhead gantries as well as normal traffic lanes and hard shoulders. So why should you obey the red X sign?

Variable Speed Limits

Speed limits are enforced on ‘dynamic hard shoulder’ stretches of motorway, such as by the use of speed cameras. When no speed limit is displayed, drivers must adhere to the national speed limit of 70mph.

Drivers must respond to variable speed limits quickly, as there is a lag of 10 seconds between when the speed limit is changed and when the cameras will begin to enforce it. Therefore, it is important to be aware of this and adjust your speed accordingly.

Failure to obey the variable speed limits can result in a fine of up to £2,500.

Emergency Refuge Areas

£390 million has been allocated for public funding. This money will be used to create more refuge areas and purchase technology to detect stopped vehicles. Emergency refuge areas (ERAs) are lay-bys placed at intervals along the road for drivers in trouble, spaced at least 1.5 miles apart, with large blue and orange signs and an orange road surface. Telephones for drivers to call services for help are also available.

It is important to be aware of these emergency refuge areas, as they can provide a safe place in an emergency situation.

Breaking Down on a Smart Motorway

If a driver finds themselves in a sticky situation on the motorway, what should they do? When it comes to breakdowns and accidents, there are certain steps drivers must take to ensure their safety.

If you experience a breakdown on the motorway, move to the hard shoulder and call for assistance. If you break down or have been involved in an accident on a smart motorway, attempt to use an Emergency Refuge Area (ERA). Stop your vehicle and switch on your hazard warning lights. Exit from the passenger side of your car and stand behind the crash barrier. Then use the SOS telephone provided at ERAs to speak with Highways England representatives.

But what if you can’t reach an ERA? Stay in your vehicle with your seat belt fastened – dial ‘999’ if you have access to a mobile phone! Smart motorways are designed so that ERAs are 1.6 miles apart, but if something unexpected happens while driving in any lane, stay inside your car – don’t get out! Keep wearing your seatbelt and keep those hazard warning lights active too!

It’s also recommended that motorists make arrangements for their own recovery in case of a breakdown by carrying details of a recovery provider with them at all times. And if you’re unable to get off the motorway or find an emergency area, call Highways England on 0300 123 5000 for help – SignLive service is available 24/7 for those who cannot use emergency roadside phones (but remember this service is only provided for one vehicle!).

In short, when faced with trouble on the road, know how best to protect yourself by following these simple steps! Move safely onto hard shoulders or ERAs; wear seatbelts; activate hazard warning lights; contact Highways England via SOS telephones or 0300 123 5000; arrange own recovery plans just in case… Got it? Great!


Smart motorways are a modern, technologically advanced development designed to improve traffic flow and reduce congestion on motorways. These motorways are divided into three basic types – Dynamic Hard Shoulder Running, All Lane Running, and Controlled Motorway – each of which have their own rules and benefits for drivers. Variable Speed Limits, red X signs, and Emergency Refuge Areas that mark smart motorways also help to increase safety on the roads, as well as providing drivers with a defense if they experience a breakdown, as it allows them access to safer havens and emergency assistance.

Overall, the advantages of smart motorways far outweigh any potential risks and make driving these roads a much more pleasant experience. This article has shown us why smart motorways are the way of the future, and how understanding how they work can help keep you safe.

Frequently Asked Questions

What is difference between motorway and smart motorway?

The difference between traditional motorways and smart motorways is that the latter use varying speed limits, CCTV cameras and sensors to actively manage traffic flow and reduce congestion. Smart motorways also provide dynamic lanes closures and hard shoulder driving, allowing for a more efficient commute.

What is the point of a smart motorway?

Smart motorways use technology and operational changes to reduce congestion and improve journey times on the roads. The technology includes variable speed limits, an Active Traffic Management system which can open or close lanes, and using the hard shoulder as an extra lane for traffic flow.

This helps decrease journey times, safely increase capacity, and guarantee smoother and safer journeys for millions of drivers every year.

How do you know if you are on a smart motorway?

You can tell if you are on a smart motorway by the presence of three or more lanes of running traffic and an additional one that remains as a traditional hard shoulder.

Furthermore, variable speed limits may also be present.

What is an example of smart motorway?

Smart motorways, such as the western section of the M25 in England, feature variable speed limits monitored remotely and use the hard shoulder only in emergencies. This enables efficiently managing traffic by adjusting speed limits and helping with lane closures for maintenance or for breakdowns.

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