M25 motorway
The M25 or London Orbital Motorway is a major ring road encircling most of Greater London. The motorway is one of the most important roads in the UK and one of the busiest. Margaret Thatcher opened the final section in 1986, making the M25 the longest ring road in Europe upon opening. The Dartford Crossing completes the orbital route but is not classed as motorway; it is classed as a trunk road and designated as the A282. In some cases, including notable legal contexts such as the Communications Act 2003, the M25 is used as a de facto alternative boundary for Greater London.
In the 1944 Greater London Plan, Patrick Abercrombie proposed an orbital motorway around London. This evolved into the London Ringways project in the early 1960s, and by 1966, planning had started on two projects, Ringway 3 to the north and Ringway 4 to the south. By the time the first sections opened in 1975, it was decided the ringways would be combined into a single orbital motorway. The M25 was one of the first motorway projects to consider environmental concerns and almost 40 public inquiries took place. The road was built as planned despite some protests that included the section over the North Downs and around Epping Forest which required an extension of the Bell Common Tunnel.
Although the M25 was popular during construction, it quickly became apparent that there was insufficient traffic capacity. Because of the public inquiries, several junctions merely served local roads where office and retail developments were built, attracting even more traffic onto the M25 than it was designed for. The congestion has led to traffic management schemes that include variable speed limit and smart motorway. Since opening, the M25 has been progressively widened, particularly near Heathrow Airport where it is a dual six-lane carriageway.
Description
Route
The M25 almost completely encircles Greater London and passes briefly through it, in the east and west. Junctions 1A–5 are in Kent, 6–13 are in Surrey, 14 and a small part of 15 are in Hillingdon, Greater London, 15–16 are in Buckinghamshire, 17–24 are in Hertfordshire, 25 is in Enfield, Greater London and 26–31 are in Essex. Law enforcement on the road is carried out by an integrated group made up of the Metropolitan, Thames Valley, Essex, Kent, Hertfordshire and Surrey police services. Primary destinations signed ahead on the motorway include the Dartford Crossing, Sevenoaks, Gatwick Airport, Heathrow Airport, Watford, Stansted Airport and Brentwood.To the east of London the two ends of the M25 are joined to complete a loop by the non-motorway A282 Dartford Crossing of the River Thames between Thurrock and Dartford. The crossing consists of twin two-lane tunnels and the four-lane QE2 bridge, with a main span of. Passage across the bridge or through the tunnels is subject to a charge between 6 am and 10 pm, its level depending on the kind of vehicle. The road is not under motorway regulations so that other traffic can cross the Thames east of the Woolwich Ferry; the only crossing further to the east is a passenger ferry between Gravesend, Kent, and Tilbury, Essex.
At junction 5, the clockwise carriageway of the M25 is routed off the main north–south dual carriageway onto the main east–west dual carriageway with the main north–south carriageway becoming the A21. In the opposite direction, to the east of the point where the M25 diverges from the main east–west carriageway, that carriageway becomes the M26 motorway. From here to junction 8, the M25 follows the edge of the North Downs close to several historic buildings such as Chevening, Titsey Place, Hever Castle and Chartwell. The interchange with the M23 motorway near Reigate is a four-level stack; one of only a few examples in Britain. Past this, the M25 runs close to the Surrey Hills National Landscape.
To the west, the M25 passes close to the edge of Heathrow Airport, and within sight of Windsor Castle. North of this, it goes under the Chalfont Viaduct railway bridge, completed in 1906, which carries the Chiltern Main Line. Red kites can often be seen overhead to the north of this, up to junction 21. The northern section of the M25 passes close to All Saints Pastoral Centre near London Colney, Waltham Abbey and Copped Hall. This section also features two cut-and-cover tunnels, including the Bell Common Tunnel. The north-eastern section of the motorway passes close to North Ockendon, the only settlement of Greater London situated outside the M25. It then runs close to the Rainham Marshes Nature Reserve before reaching the northern end of the Dartford Crossing.
In 2004, following an opinion poll, the London Assembly proposed aligning the Greater London boundary with the M25. "Inside the M25" and "outside/beyond the M25" are colloquial, looser alternatives to "Greater London" sometimes used in haulage. The Communications Act 2003 explicitly uses the M25 as the boundary in requiring a proportion of television programmes to be made outside the London area; it states a requirement of "a suitable proportion of the programmes made in the United Kingdom" to be made "in the United Kingdom outside the M25 area", defined in Section 362 as "the area the outer boundary of which is represented by the London Orbital Motorway ".
Sections of the M25 form part of two long-distance E-roads, designated by the United Nations Economic Commission for Europe. The E15, which runs from Inverness to Algeciras, follows the M25 and A282 clockwise from the A1 at junction 23 to the M20 at junction 3; while the E30 Cork to Omsk route runs from the M4 at junction 15, clockwise to the A12 at junction 28. The United Kingdom is formally part of the E-roads network but, unlike in other countries, these routes are not marked on any road signs.
Features
The M25 was originally built mostly as a dual three-lane motorway. Much of this has since been widened to dual four lanes for almost half, to a dual five-lanes section between junctions 12 and 14 and a dual six-lane section between junctions 14 and 15. Further widening is in progress of minor sections with plans for smart motorways in many others.Two motorway service areas are on the M25, and two others are directly accessible from it. Those on the M25 are Clacket Lane between junctions 5 and 6 and Cobham between junctions 9 and 10. Those directly accessible from it are South Mimms off junction 23 and Thurrock off junction 31.
As is common with other motorways, the M25 is equipped with emergency telephones. These connect to two National Highways operated control centres at Godstone and South Mimms. The Dartford Crossing has a dedicated control centre. There is an extensive network of closed-circuit television on the motorway so incidents can be easily identified and located. A number of 4×4 vehicles patrol the motorway, attempting to keep traffic moving where possible, and assisting the local police. They can act as a rolling roadblock when there are obstacles on the road.
When completed, the M25 only had street lighting for of its length. Originally, low pressure sodium lighting was the most prominent technology used, but this has been gradually replaced with high-pressure sodium lighting. the motorway has more than 10,000 streetlights. The M25 has a number of pollution control valves along its length, which can shut off drainage in the event of a chemical or fuel spill.
History
Plans
The idea of a general bypass around London was first proposed early in the 20th century. An outer orbital route around the capital had been suggested in 1913, and was re-examined as a motorway route in Sir Charles Bressey's and Sir Edwin Lutyens' The Highway Development Survey, 1937. Sir Patrick Abercrombie's County of London Plan, 1943 and Greater London Plan, 1944 proposed a series of five roads encircling the capital. The northern sections of the M25 follow a similar route to the Outer London Defence Ring, a concentric series of anti-tank defences and pillboxes designed to slow down a potential German invasion of the capital during World War II. This was marked as the D Ring on Abercombie's plans. Following the war, 11 separate county councils told the Ministry of Transport that an orbital route was "first priority" for London.Plans stalled because the route was planned to pass through several urban areas, which attracted criticism. The original D Ring through northwest London was intended to be a simple upgrade of streets. In 1951, Middlesex County Council planned a route for the orbital road through the county, passing through Eastcote and west of Bushey, connecting with the proposed M1 motorway, but it was rejected by the Ministry two years later. An alternative route via Harrow and Ealing was proposed, but this was abandoned after the council revealed the extent of property demolition required.
In 1964, the London County Council announced the London Ringways plan, to consist of four concentric motorway rings around London. The following year, the transport minister Barbara Castle announced that the D Ring would be essential to build. The component parts of what became the M25 came from Ringway 3 / M16 motorway in the north and Ringway 4 in the south.
The Ringways plan was controversial owing to the destruction required for the inner two ring roads,. Parts of Ringway 1 were constructed, despite stiff opposition, before the overall plan was postponed in February 1972. In April 1973, the Greater London Council elections resulted in a Labour Party victory; the party then formally announced the cancellation of the Ringways running inside Greater London. This did not affect the routes that would become the M25, because they were planned as central government projects from the outset.
Construction
There was no individual public inquiry into the M25 as a whole. Each section was presented to planning authorities in its own right and was individually justified, with 39 separate public inquiries relating to sections of the route. The need for the ministry to negotiate with local councils meant that more junctions with local traffic were built than originally proposed. A report in 1981 showed that the M25 had the potential to attract office and retail development along its route, negating the proposed traffic improvements and making Central London a less desirable place to work. None of the motorway was prevented from being built by objections at the public inquiries. However, as a consequence of the backlash against the Ringways, and criticism at the public inquiries, the motorway was built with environmental concerns in mind. New features included additional earth mounds, cuttings and fences that reduced noise, and over two million trees and shrubs to hide the view of the road.Construction of parts of the two outer ring roads, Ringways 3 and 4, began in 1973. The first section, between South Mimms and Potters Bar in Hertfordshire opened in September 1975. It was provisionally known as the M16 and was given the temporary general-purpose road designation A1178. A section of the North Orbital Road between Rickmansworth and Hunton Bridge was proposed in 1966, with detailed planning in 1971. The North Orbital Extension was given the go-ahead in January 1973, from Maple Cross. It was, and was to cost £6.5million. The road was constructed to motorway standards and opened on Thursday 26 February 1976, as a section of the A405. It eventually became part of the M25's route. The section to the south, from Heathrow Airport to Rickmansworth had five separate routes proposed when a public inquiry was launched in 1974. The Department of Transport sent out 15,000 questionnaires about the preferred route, with 5,000 replies. A route was fixed in 1978, with objections delaying the start of construction in 1982.
The southern section of what became the M25 through Surrey and Kent was first conceived to be an east–west road south of London to relieve the A25, and running parallel to it, with its eastern end following the route of what is now the M26. It was originally proposed as an all-purpose route, but was upgraded to motorway standard in 1966. It was the first section of the route announced as M25 from the beginning. The first section from Godstone to Reigate was first planned in 1966 and opened in February 1976. A section of Ringway 3 south of the river between Dartford and Swanley was constructed between May 1974 and April 1977.
File:Bell Common Tunnel - geograph.org.uk - 53233.jpg|thumb|left|Inside the Bell Common Tunnel near Epping
In 1975, following extensive opposition to some parts of Ringway 3 through Middlesex and South London, the transport minister John Gilbert announced that the north section of Ringway 3 already planned would be combined with the southern section of Ringway 4, forming a single orbital motorway to be known as the M25, and the M16 designation was dropped. This scheme required two additional sections to join what were two different schemes, from Swanley to Sevenoaks in the south-east and Hunton Bridge to Potters Bar in the north-west. The section of Ringway 3 west of South Mimms anti-clockwise around London to Swanley in Kent was cancelled.
The section from Potters Bar to the Dartford Tunnel was constructed in stages from June 1979 onwards, with the final section between Waltham Cross to Theydon Garnon opening in January 1984. This section, running through Epping Forest, attracted opposition and protests. In 1973, local residents had parked combine harvesters in Parliament Square in protest against the road, draped with large banners reading "Not Epping Likely". As a consequence of this, the Bell Common Tunnel that runs in this area is twice as long as originally proposed.
The most controversial section of the M25 was that between Swanley and Sevenoaks in Kent across the Darenth Valley, Badgers Mount and the North Downs. An 1,800-member group named Defend Darenth Valley and the North Downs Action Group argued that the link was unnecessary, it would damage an Area of Outstanding Natural Beauty and it would be primarily used by local traffic as a bypass for the old A21 road between Farnborough and Sevenoaks. After a length inquiry process, chaired by George Dobry QC, the transport minister Kenneth Clarke announced the motorway would be built as proposed.
The section from the M40 motorway to the 1970s North Orbital Road construction opened in January 1985. The route under the Chalfont Viaduct meant the motorway was restricted to a width of three lanes in each direction.
The Prime Minister, Margaret Thatcher, officially opened the M25 on 29 October 1986, with a ceremony in the section between junctions 22 to 23. To avoid the threat of road protesters, the ceremony was held a quarter of a mile from the nearest bridge. The total estimated cost of the motorway was around £1billion. It required of concrete, of asphalt and involved the removal of of spoil. Upon completion, it was the longest orbital motorway in the world at. At the opening ceremony, Thatcher announced that had been constructed while the Conservative Party were in office, calling it "a splendid achievement for Britain". A 58-page brochure was published, commemorating the completion of the motorway.