Originally a brief account of this tale existed on the Botched Motorways page but the M23 is more interesting than that brief outline, so I did some more research and dredged through some aerial photos and managed to produce this page, which should keep even the most die-hard M23 fan happy. Providing there are, of course, any die-hard fans of the M23.
There had been plans in the national scheme for motorways since the mid-1960s to construct a new motorway to take traffic heading from London to the south coast. The existing road, the A23, was mostly single carriageway and little improved since it had been given the number in the 1920s. Worse, it passed through the town centres of Croydon, Redhill and Crawley. Traffic on the route was sluggish and many motorists were put off going to Brighton simply because it was hard to get there. The motorway plan was simple - build a new one to bypass the A23 running from south London to the far side of Crawley, from where the A23 should be clearer, and do for the south what the M1 had done in the north.
The Wider Scheme
The M23 would obviously not have worked on its own. Completion of the M1 (finally done to Staples Corner in 1977) was waiting for the upgrade of the A406 North Circular Road, simply so it would be able to cope with the influx of traffic fresh from a motorway. The same was needed for the M23, as this was part of the original plan for improvements to London's roads. In a nutshell, new motorway or motorway-standard roads would be run around and through London to form a series of ring roads and radial roads. The M23 was to end on Ringway 2, essentially the South Circular, which was to become the same standard as the A406 is today.
The Plan in Detail
Unfortunately, the first problem was hit straight away simply with the logistics of the plan. South London, especially around Croydon, is thickly developed with no real open space outside of a handful of small patches of wasteland. There wasn't the scope to find a corridor of empty or cheap land as there had been in the north and so something more radical had to be considered. To make the M23's alignment through London work, planners were forced to use every urban motorway trick that was known to find room.
From the north, the motorway began on Ringway 2 - a short section of which would have been part of the motorway scheme, linking the A23 and A24. From Streatham it was to head down a railway line. Land was available along the south-east side of a line leading from Streatham towards Mitcham. This line leads into Mitcham Common, a wide area of open wasteground between industral areas - easy to find room for a motorway. It crossed Mitcham Junction station and then went across a sewage farm before reaching the south side of the Common.
The next part was the most difficult. Forming a wall between Mitcham Common and the open land south of Wallington was (and still is) a vast swathe of housing estates. There was no gap, no open space, no parkland or wide streets. From here, the only way through was with a bulldozer. A line taking the route of least demolition was adopted, following one side of an existing street until it thankfully reached open land again and headed south once more.
After slicing through Big Wood (and why not - we just demolished a load of houses) we hit another obstacle, this time one created by nature: the Chipstead Valley. Steep-sided and with a picturesque village squashed into the bottom, this was not good news. The only way across was over, and so eight traffic lanes were to mout concrete pillars and fly over the top of Chipstead, its valley, houses, schools and golf course. Once at the top, a slight turn to the south east found an easy line across open country toward Crawley.
The Long Wait
Work on the M23 couldn't even begin until there was concrete evidence (literally) that a suitable road would be available to receive it at its northern end. However, traffic was horrific along the entire route and so a decision was made in the late 1960s to begin work on the southern sections outside the London area.
In January 1972 work began on the section from junction 7 to 8 (A23 to M25) and the section of M25 that it connected to. This part (all of two miles) was ready to open in December 1974, but did not open until the completion of the neighbouring section of the M25 which was delayed. In February 1972, work also began on the next section from junction 8 to 11 (M25 to A23 south of Crawley). Work also started in April 1974 on the connecting spur from the M23 to Gatwick Airport, and this and the second section both opened in November 1975.
Plans did not exist for a section from Crawley to Brighton at this point, though had the section through London been built it would have been a logical next step.
In 1984, in his book "A History of British Motorways", George Charlesworth said:
"Roads on the south side of London are widely regarded as inadequate; the so-called South Circular route and inner ring road have been described as "no more than signposted routes". As it stands the route appears not to be suitable for terminating radials from the outer areas and as there are no plans for improving the route proposals for new radials are in doubt. Indeed the Department of Transport is abandoning proposals it made in 1968 for the extension of the M23 northwards from Hooley to Mitcham where it would have connected with the erstwhile Ringway 2."
Oh dear. By the mid 1980's, the DOT had all but given up all hope of an M23 heading anywhere north of its temporary ending at Hooley. Why?
Understandably, since the plans had been around since 1968, many local residents had noticed them and started to wonder exactly how close this new motorway would come to their homes. The NIMBY effect grew rapidly and by 1984 even if the Department of Transport had wanted to build the M23 the scheme would probably have ground to a screaming halt during the public inquiry stage.
There were also the small matters of cost and government policy: Since the plans were formed in 1968, the tide had turned and the government no longer wanted to encourage urban motorway building, especially in residential and inner city areas. The M23 would have been in both of those, so from the early 1970s it was unlikely. The price to be paid for building any motorway was also spiralling. Since the M1's construction for a few million pounds in the 1950s - mere pocket money by today's standards - not only had design standards and build quality increased, but the price of materials and labour had skyrocketed so that even a simple rural motorway was costing a phenomenal amount of money by comparison. Building an urban motorway on the scale of the M23 was a decreasingly sound investment.
The M23 may only exist in a half of its intended length from London to Crawley, but the northern section was, at one stage, definite, and it has left an imprint on south London (better shown up in the aerial photo). Until 1995, the DOT (and its succesors) still owned some of the land along the route and some has yet to be developed. In fact, a large tell-tale line of empty or recently-developed land exists along the railway north from Mitcham and there are open gaps between houses in Beddington just nicely wide enough for six traffic lanes and a pair of hard shoulders.
The northern terminus of the M23 is an even bigger tribute to the failed project: empty flyovers cross a diverted A23, and the M23 suddenly drops to two lanes before piling all its traffic onto what should be slip roads and subsequently having to merge with the A23.
The biggest reminder that the M23 was going to be built is, of course, the road it should have relieved. The A23 through central Croydon is probably London's most pathetic radial route. Two lanes of single carriageway road full of roundabouts, traffic lights and parked cars carry the traffic of a six lane motorway.
It seems that the M23 was killed off by 'selfish' local residents who demanded a motorway plan be halted so that they had a quieter back garden. However, this is very much unfair to the people of Streatham, Mitcham and Beddington: most people in the same situation would do exactly the same. The NIMBY factor was simply the last straw, the thing that made the DOT give up after years of setbacks. The main factor is really the GLC's grand plan for orbitals and radial roads around London; the M23 relied entirely on the A205's upgrade as "Ringway 2" but for the same reasons as the M23's route was hard to find, the plan was scrapped. Without Ringway 2, the M23 could never work and once it is accepted that Ringway 2 could never work either it seems incredible that the M23 ever seemed possible.
A selection of images to help put the M23 plans into context. Principal among them is the annotated aerial image of the whole route. There are also some map scans showing the 'projected' line from the 1970s.
Annotated aerial image
JPG file (832Kb) aerial.jpg
Route on A-Z map
JPG file (200Kb) a-z.jpg
A-Z map showing proposed line*
JPG file (252Kb) a-z-prop.jpg
1976 RAC map showing route**
JPG file (136Kb) 1976.jpg
1980 Philip's map showing route
JPG file (116Kb) 1980.jpg
* A-Z with proposed line provided by Simon.
** 1976 RAC Scan provided by Trevor Osborne.
With thanks to Rob James and Ben for information on this page, and special thanks to Tony Frost, without whom this page would not have been possible.