The Future of Roads - Smart Motorways

Smart Motorway Concept - MAT Foundry

The very first smart motorway was implemented on the M42 east of Birmingham back in 2006. This pilot programme examined the effects of using monitoring technology to manage and enhance traffic flow efficiency, instead of committing to road widening construction programmes.

The data gathered by that first scheme ascertained that journey reliability on Smart motorways could be improved by 22%, and also that the number of accidents that resulted in injury was reduced by half while their severity was also significantly reduced.

These positive results led to their rollout across vast areas of the motorway network, with multiple sections of the M1, M3, M4, M5, M6, M20, M25, M40, M42, M62 and the M90 currently under ‘Smart’ management, and many other sections either already under construction or planned to be converted in the near future.

What is a Smart Motorway

How a Smart motorway works is to actively monitor traffic flow and congestion, and enact real time changes to lane availability and speed limits to increase efficiency. The data is fed into control centres which make decisions based on the information and circumstances surrounding each situation.

The simplest action they could take would be to open up the hard shoulder to traffic to ease congestion. To enable the hard shoulder to be used like this, additional emergency refuge areas (ERA) have been constructed, spaced on average every 2000m or 75 seconds (at 60mph) apart to provide drivers somewhere to stop.

Another action would be to reduce the speed limit to maintain traffic flow and eliminate stationary traffic. Stationary traffic is to be avoided as much as possible as it causes more driver frustration and more accidents. By reducing the speed limit on specific stretches of road they can smooth out congestion and keep everyone moving.

A more serious consideration could be in the event of an accident where emergency vehicles need access to the accident, a lane could be closed to traffic to allow them to reach the site quickly.

There are three types of Smart motorway in use on the motorway network, each with slightly different levels of capability depending on what the has been deemed safe for the each stretch of carriageway:

Controlled motorway – does not allow the use of the hard shoulder as an additional lane, but can vary speed limits in accordance with traffic flow.

Dynamic hard shoulder – allows the occasional use of the hard shoulder as an extra lane to reduce congestion, as well varying speed limits.

All lane running – can vary speed limits, and the hard shoulder has been permanently converted into an additional lane for traffic.

UK Smart Motorway - MAT Foundry

Not Perfect

Critics of the scheme disagree with the claims made by the Highways agencies, and maintain the schemes are no substitute for widening roads to increase capacity – calling it widening on the cheap.

Police forces currently seeing their budgets stretched thinner than ever haven’t seen any of the saved money find its way back to them. Increased numbers of officers would improve safety by catching dangerous drivers - after all, a camera can catch a speeding driver but it doesn’t stop drivers tailgating or dangerously changing lanes, which both cause significant numbers of accidents.

It adds more fuel to the fire that the scheme is an undercover method to completely line the nations motorways with cameras as a means to generate income through speeding fines – exacerbated by the variable speed limits and lane closures instantly imposed by Smart motorways at the push of a button.

Those against the schemes also raise safety concerns about the removal of hard shoulders. They believe it more dangerous for workers carrying out work on or near the carriageway without the safety buffer the lane provides. Police forces have also raised concerns about their ability to pull over dangerous drivers without a hard shoulder,

With the nation’s roads becoming ever more congested only time will tell if Smart motorways can manage the increased load, but whatever your view they are here to stay for mid-term at least. In a first for the ‘Future of our Roads’ series, it’s unclear as to whether the effect of this technology will be truly positive or not.