The rise and fall of the second hard shoulder

Published on 20 September 2017

It sometimes seems that the hard shoulder is a thing of the past, happily discarded on many motorways to create another lane. Once upon a time, though, the hard shoulder was so indispensable that some roads were thought to need two of them on each side.

It's happening everywhere these days - All Lane Running, the feature of Smart Motorways that is likely to gradually take the place of "dynamic hard shoulders" and all the other experiments. ALR is, of course, a euphemism for using the hard shoulder as a permanent running lane.

Today, long lengths of the M25 operate as a dual four-lane motorway with no hard shoulder at all, as do other motorways, and within a few years the same will be true of the whole M1 between the M25 and M6. Highways England, it seems, now consider hard shoulders to be very much an optional extra for their motorways - nice to have, maybe, but not at all necessary.

It hasn't always been this way. Wind the clock back half a century, to a time when cars were far less reliable than today, when maintenance was something you'd often need to do at the roadside, and no high-speed road worth its name could be considered safe or respectable without a paved strip at the roadside to allow vehicles to pull out of the stream of traffic to a place of safety.

The M6 Preston Bypass, as originally designed, with its "reinforced" unpaved shoulder. Click to enlarge
The M6 Preston Bypass, as originally designed, with its "reinforced" unpaved shoulder. Click to enlarge

The hard shoulder, here in the UK, started out as a strip of "reinforced" earth alongside the Preston Bypass, and the first section of the M1 started out with the same. Stories of jacks pushing themselves into the ground instead of lifting up stricken vehicles were rife, and it wasn't long before those shoulders gained a hard top, and the "hard shoulder" became an essential part of the design specification for all new motorways.

Far from safety

Through the 1960s, roads got wider and wider and plans grew ever more ambitious. As urban planners began pencilling in vast motorway networks, it became clear that many of them would require more than three lanes each way. The first question that arose, in a country that had scarcely any high speed roads with more than even two lanes each way until a decade previously, was: will these roads be safe?

The hard shoulder was the place of safety, of course; the thing that made motorways by far the safest type of road. Heads were scratched. If your car made a distressing mechanical sound and black smoke started coming from under the bonnet as you raced along, could you coast across to the far left-hand side of the road quickly and safely? From lanes 1 and 2, yes. From lane 3, yes, just about. From lane 4? Nobody could be sure. A fourth lane seemed too far from the safety blanket.

So the design specification, in the late 1960s, was amended. If a motorway had more than three lanes each way, it must have hard shoulders on both sides of both carriageways, four in total.

Doubling up

As odd as it might sound today, those second hard shoulders (or offside hard shoulders, if you prefer) were a very serious consideration. By 1968, they were a very necessary part of four-lane motorways - not that any had yet been built.

In November 1968, under the headline "Fight against London Motorway Box begins", The Times ran a story that quoted Robert Vigars, the chairman of the Greater London Council's planning and transportation committee, describing the urban motorways planned for central London. Even in London where space was at a premium and land was the biggest cost in roadbuilding, the considerable extra width of those extra hard shoulders was considered necessary.

"Mr. Vigars said that eight-lane roads with centre hard shoulders would be about 147ft. wide and six-lane roads without them 110ft. wide."

The Times, 20 November 1968

Interestingly, the first section of motorway with four lanes on each side is thought to be the M61 through Worsley Braided Interchange, at Linnyshaw Moss near Bolton in Lancashire, which doesn't have second hard shoulders at all. Perhaps, because the four-lane carriageways are relatively short and part of an extended interchange complex, they were thought not to need the extra safety feature.

The wide open spaces of Linnyshaw Moss include four lanes each way but just two hard shoulders. Click to enlarge
The wide open spaces of Linnyshaw Moss include four lanes each way but just two hard shoulders. Click to enlarge

The theoretical requirement

Roads with four or more lanes on each side were extremely rare in the 1960s and 70s, so the design standard that called for extra hard shoulders was almost entirely theoretical for a long time. It got a rare outing when a section of the M25 was being designed west of London.

Between junctions 14 and 15 - the junctions for original spur to Heathrow at Stanwell Moor and the M4 - traffic forecasts indicated that the road would be so busy when it opened that it would need four lanes each way, not three. So that section - opened in 1985 - was designed with four lanes each way and a full set of central reservation hard shoulders.

Unfortunately for those of us who study and appreciate the history of the hard shoulder (and if you're reading this, you are now included in that category), the centre hard shoulders on the M25 were to remain theoretical. Before the road opened, the Police expressed concern about the safety of pulling over in a narrow gap between the fastest lane on the road and the central reservation barrier, and flatly refused to condone their use. So Britain's only central reservation hard shoulders were covered with earth mounds before the road opened, ensuring they would never be used. In later years the spare carriageway surface was used for road widening, and that section has been entirely rebuilt with a full six lanes in each direction - but still just one hard shoulder.

Six lanes side by side on the M25 near Heathrow - but just one hard shoulder on each side. Click to enlarge
Six lanes side by side on the M25 near Heathrow - but just one hard shoulder on each side. Click to enlarge

Since 1985, of course, we've gained lots of new four lane motorway, none of which has had a centre hard shoulder, and design standards haven't called for one for a long time. In fact we now have an awful lot of motorway with four lanes and no hard shoulder at all.

Did we ever get a centre hard shoulder? Anywhere?

Safety on both sides

Well yes we did, in just one place. In 1973, Northern Ireland proudly opened the section of the M2 motorway leading north from Belfast to Greencastle, between what are now junctions 1A and 2, with variously four and five lanes on each side. There might only be a couple of miles of it, but it has something no other motorway in the UK possesses: a pair of fabled centre hard shoulders.

The M2 north of Belfast, with its unique centre hard shoulders highlighted in red. Click to enlarge
The M2 north of Belfast, with its unique centre hard shoulders highlighted in red. Click to enlarge

Not content with just having a hard shoulder on both sides of both carriageways, the M2 actually has them coloured red to make it clear they're not running lanes. There are even emergency telephones in the central reservation. This is a motorway that really knows how to live.

Were it not for that one bit of motorway, with the magic combination of being designed to a specification that was beyond anything needed for most roads even today and reaching construction stage when most of its urban motorway contemporaries fell by the wayside, we would have nothing at all to show for a remarkably strange and perhaps over-cautious design standard from the early days of the motorway era. It has left us with something never seen before or since: the elusive, almost mythical, second hard shoulder.


Tom Stewardson 20 September 2017

There are central hard shoulders in (at least) one other place on the motorway network: the M6 over Thelwall Viaduct. The very wide left hand hard shoulder and the existence of the right hand one, especially on the northbound viaduct, highlight the original function of the structure - to carry 3 lanes in each direction.

Something like a hard shoulder does exist on the northbound Thelwall Viaduct for exactly the reason you suggest - but it's worth noting that not only was it not intended to be used as a hard shoulder, it's actually got a kerb protecting it so it's not actually part of the roadway at all.

The design did not call for a central reservation hard shoulder, which is why the newer southbound Thelwall Viaduct, built when the road was widened to four lanes, hasn't got one. What it does have is an extra-wide normal hard shoulder and a hard strip next to the central reservation that intentionally provide enough room for future widening to five lanes.

Chris Lawrence 21 September 2017

Interestingly enough, a full-lane-width (12 ft) inner hard shoulder is a long-standing requirement for freeway construction in the U.S. under AASHTO standards, and kicks in at three or more through running lanes, not four (auxiliary lanes between interchanges don't count), and is incredibly common. It can be waived as a design exception to reduce costs for an in-place widening, though, particularly in urban areas.

ALR of course hasn't really caught on at all; the only example I can think of is the part-time ALR on I-66 west of I-495 in Virginia.

The NJ Turnpike, I-95 for 2/3 of its length, has taken that standard farther. The vast majority of its two lane roadways have both inner and outer shoulders, as do all bridges. Only short stretches of the outer roadway near junctions may not always have inner shoulders, but they return soon after. The only turnpike roadways without inner shoulders are I-78 near the Holland Tunnel and I-95 itself at Fort Lee. The turnpike authority actually bought this 4 mile stretch of motorway from the state (to balance the budget) in 1992, so it clearly was not built to their standards.

Mark Whittingham 21 September 2017

Didn't we have some obscure rules where because the hard shoulder was too narrow, a road could not be a Motorway? M27 near Portsmouth springs to mind..... To me a hard shoulder is essential. They make a motorway a motorway! Near me, the A2 had laybys built to cater for breakdowns, but within a few years, complete hard shoulders were constructed.....

I don't believe such a rule ever existed - as I mentioned in the blog post, the original motorways had no hard shoulder in the modern sense, and plenty of motorways were built even in the 60s and 70s without hard shoulders.

The story specifically relating to the A27 between the M27 and A3(M) is found on the UK Motorway Archive: the land acquired for the road was too narrow for a full motorway formation by less than a foot, and the County Surveyor responsible for the scheme pedantically declared that, on that basis, it could not be a motorway. It was rather a daft distinction to make as the adjoining section of the M275, opened at almost the same time and presumably under the direction of the same County Surveyor, is a motorway despite having much narrower hard shoulders than the A27.

David 21 September 2017

I would argue there are now many parts of the GB motorway network which have partial central hard shoulders - but they have never been designated as such. Upgrades to Smart Motorway usually replace the central metal barrier and turf with a concrete barrier and tarmac - tarmac which in many places is about a car's width and (for all-lane running) the only hard shoulder the motorway has at that stage...
Unlike those in NI they don't have emergency phones though.

This does often happen on Smart Motorway schemes, but not with the intention of creating a hard shoulder. Paving the central reservation makes it much lower maintenance (with no grass to mow) and the slip-formed concrete barrier is usually narrower than the original so there is more space behind the white line. In some places extra space is left for forward visibility on the inside of a curve.

I wouldn't advise stopping adjacent to the central reservation on these roads!

Andrew 24 September 2017

Regarding the emergency phones on the M2 when a double concrete barrier was installed a few years ago it had the effect of narrowing the hard shoulders. Since then the central phones have been bagged up, presumably to discourage use of the hard shoulder altogether.

Will M 22 December 2017

The M2 NI foreshore was on one of those Police Camera Action programmes, Alistair Stewart shouted that the central reservation is no place to stop for the police - it is a hard shoulder and quite often the police will have pulled someone up here, causing the far outside lane to slow to a crawl for safety / rubberneckers.

Though within the past decade, improvements to the central barrier have narrowed the central hard shoulder, and the old red tarmac of NI hard shoulders is slowly being lost to GB style black tarmac when resurfacing occurs.

The motorway itself actually works more like 2 parallel motorways, as you can see on the picture, with traffic divided between the M2 and M5 northbound, and "M2" (actually end of motorway to a halt at traffic lights before the A12 westlink) and the M3 (which like the M5 is more of a stub) southbound. The Fortwilliam roundabout junction causes some weaving across and prevents a physical M8 style carriageway separation.

It actually saved my uncle's bacon when his knackered Ford conked out on the 2nd-from-outside lane, was able to swerve it to the centre. Getting a tow out onto the outside lane was scary though.

Asriel 16 October 2022

There is an inside hard shoulder on the northbound M1 near Sheffield, but unfortunately lacks a second as where it should be, is striped off.

That’s just a paved central reservation, in which the concrete barrier is close against the southbound carriageway rather than in the middle, possibly for drainage or forward visibility reasons. It’s not designed as a hard shoulder and has no facilities for stopped vehicles. 

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