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London’s turning circle

Love it or loathe it, the M25 was a significant engineering achievement and is now a vital part of the UK’s transport infrastructure. NCE celebrates the road’s 25th birthday. By Margo Cole.

Last weekend saw the nation celebrate the 25th anniversary of completion of the 146km M25 orbital motorway around London. The final section of the road was opened on 29 October 1986 by then prime minister Margaret Thatcher.

Speaking at an event to mark the anniversary, current roads minister Mike Penning described the opening in 1986 as “a celebration of engineering excellence”, adding that “the M25 has been, and continues to be, a catalyst for economic growth”.

Staged construction

Construction of the motorway was undertaken in stages, with the full route taking 11 years to build at a cost of £909M - the equivalent of £7.5M per mile.

At the time of the opening NCE described the orbital motorway as “simply a triumph for the road construction industry”, adding: “It is to the credit of the dozen or more major contractors and handful of top consultants that the M25 has been completed largely on time and to budget.”

“When the motorway opened traffic on the busiest section, around Heathrow airport, peaked at 113,000 vehicles a day”

The boom that the project brought was vital to a beleaguered construction industry. “Over the last 10 years, which has seen the majority of the construction activity, investment in the motorway has generated well over 50,000 jobs and has been the lifeblood of an industry suffering through perhaps its worst recession,” reported NCE.

Plans to build a road around London date back to 1905, when a royal commission proposed a ring road at a radius of 7.7km from the centre of London, but the first detailed plans were developed in the early 1970s, following a huge growth in motor traffic. The M25 as we know it officially came into being in 1975, when various relief road projects north and south of the capital were subsumed into a single project to build an orbital ring around the city.


Nigel Russell

Nigel Russell is currently managing director of Connect Plus Services, the offshoot of M25 DBFO concessionaire Connect Plus that manages, maintains and operates the network - but his involvement with the road dates back 30 years.

As a graduate engineer with contractor Balfour Beatty, Russell worked on construction for the structures for the new road between what are now junctions 13 and 14 near Heathrow airport. “There was a lot of work around the south west corner being built at the time, so we did feel that it was just a cog at that stage,” he says.

But that impression changed when Russell returned to the orbital road five years later as a sub agent on construction of the M25/M1 interchange - one of four contracts undertaken together that made up the final link in the 187km ring around London.

“The whole thing became a reality on that job,” he says. “Prime minister Margaret Thatcher coming to open it showed the national importance of the M25, and it was quite something to be invited to that [the opening ceremony].”

Russell’s career took in other major motorway projects, including the M6 and M40, as well as a stint in the rail sector, but he returned to the M25 in 2008 when Connect Plus took over day to day running of the motorway. Not surprisingly he feels the road gets unfairly maligned when “for 90% of the time it works very well”.

“It’s hard to think of this part of south east England without the M25,” he adds. “It’s made a real difference.”

The first section, between junctions 23 and 24, was finished later the same year, although the oldest piece of infrastructure incorporated into the motorway is the tunnel section of the Dartford Crossing, built in 1963. The final section to be completed was the 21km stretch between junctions 19 and 23 to the north of London.

When the motorway opened traffic on the busiest section, around Heathrow airport, peaked at 113,000 vehicles a day. Over the last 25 years this has increased to 200,000.

First scheme

The first widening scheme took place just four years after the road opened, when the section between junctions 11 and 13 in Surrey was upgraded to four lanes in each direction. This was followed by a similar project between junctions 6 and 10 in 1997, and subsequent schemes to widen to dual five-lane between junctions 12 and 14 and dual six-lane between junctions 14 and 15 near Heathrow.

A £1bn project has been under way since 2008 to upgrade the sections between junctions 5 and 7 in the south and junctions 16 and 30 in the north to dual four lanes under a design, build, finance and operate contract won by Connect Plus. The work is due to be completed in time for next year’s Olympics.

The M25 was the first motorway in England to trial variable mandatory speed limits as a way of reducing congestion. The system was first introduced between junctions 11 and 15 in 2005, and has since been extended to other busy sections of the route.

Hard shoulder running

Work to implement hard shoulder running between junctions 5 and 7 and junctions 23 and 27 is set to begin in 2015.

In addition to the 25th anniversary of the M25 itself, this week also marks a significant date in the history of a key piece of infrastructure on the orbital road - the 20th anniversary of the opening of the Queen Elizabeth Bridge, now part of the Dartford Crossing.

The bridge was an early example of a private finance initiative project, with the £120M construction cost funded by a private consortium in return for an operating concession. Construction began in August 1988 and the bridge was officially opened by the Queen on 30 October 1991.

At the time of the opening ceremony the Queen Elizabeth II Bridge was Europe’s largest cable-stayed bridge. It carries southbound traffic across the river Thames from Thurrock in Essex to Dartford in Kent, while northbound traffic uses the original Dartford tunnels.


Stewart Evans

Among the dignitaries gathered around prime minister Margaret Thatcher at the M25 opening ceremony in 1986 was 15-year-old schoolboy Stewart Evans, who had written to the prime minister requesting an invitation.

“It was a cold, bright day and we assembled at Radlett aerodrome,” recalls Evans. “There was a big marquee in the middle of a field, and I remember a finger buffet and things happening in a marquee before we were bussed down to junction 21A/22 where the ceremony took place.

“People said various things, and it culminated in Thatcher giving an iconic speech in which she defended the road’s capacity, saying ’ can’t stand those who carp and criticise when they ought to be congratulating Britain on a magnificent achievement’.

“She was very practical about it - moving the cones out of the way and saying she wanted to get Britain moving.”

Evans had asked for an invitation to the opening ceremony after developing a passion for civil engineering at a young age when two major road schemes were built near his Essex home. It is a passion that has continued to this day, via a career that includes stints with a contractor, two local authorities and a water company.

Now, 25 years after his first visit to the road, Evans is one of seven Highways Agency operations managers based at the organisation’s East Regional Control Centre at South Mimms, responsible for keeping traffic flowing on the motorway network in the region.

Looking back to the opening ceremony Evans says: “It was really fantastic to see something of this magnitude: six lanes of motorway going through a cutting, with all the technology on the side and the matrix signs. And stepping onto the clean black tarmac and crisp white lines I thought ‘this is great stuff’.”

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