This page was updated in January 2021
A major housing development at every junction
The official pausing of all expressway plans in March 2020 has thrown into doubt the future both of the expressway itself and the distribution of houses across the Arc. We are leaving this section of the website up, however, to show the sort of thinking behind road planning that often (as in the case of the Arc) has the objective of ‘opening up’ land for further development. EEH’s alternative plans have a similar objective.
In its 2018 Corridor Assessment Report (CAR) Highways England showed neither specific expressway routes, nor junctions along the expressway. However, enough information was given in the CAR to work out at least one possible route for the expressway going West of Oxford City and one going East. These routes are most clearly defined where they intersect the existing road network; one can ‘guess’ at possible expressway routes by simply ‘joining up the dots’. These guessed routes are shown in the map below, green for the route West of Oxford city and red for the routes (several options are shown) East of the city.
The route West of Oxford City
This leaves the A34 near Abingdon and heads towards the A420 Oxford to Swindon road which it joins and follows down to the Botley A34 roundabout. It then follows the A34 to the M40 J9 near Bicester, after which it travels first South of Bicester and then north-eastwards to align with the track of East West Rail (shown as a black line on the map).
The route East of Oxford
This also leaves the A34 near Abingdon, first travelling South of the city to meet the M40 at J8a Services. It then follows the M40 for approximately 11 kms to a new M40 junction somewhere near Boarstall/Oakley. From there it goes north-east again, eventually to run parallel to East West Rail.
The map shows three guessed routes from the new junction on the M40 because the middle route, as described in the Corridor Assessment Report (CAR), runs through Ministry of Defence (MOD) Land between Arncott and Piddington. It is thus less likely to be approved; the map shows options running both West and East of the MOD land. Finally an additional option is shown leaving the M40 J8a services and travelling cross country to reach East West Rail. This additional option would unlock the greatest amount of land for housing development, one of the objects of the expressway exercise.
We stress that all routes shown on this map are for guidance only. No one yet knows officially where any expressway route might go. Because these routes are guesses, we have put them in this Houses section of our website. When more definite information on routes is available, we will include it in the Roads section.
The dots on the routes on the map are junctions identified in the CAR (blue for the western route and yellow for the eastern one). We are able to locate these junctions approximately because Highways England identifies them by the names given in the call-outs in the map. Thus a junction called ‘Wendlebury’ by Highways England is presumably near the village of that name, South of Bicester.
A separate document on this website explains how Highways England modelled regional traffic flows to work out the spare capacity for cars of each expressway junction (link to CAR document prepared by NEG). This spare capacity is the difference between the maximum number of cars the junction could handle without traffic congestion (taken as 85% of maximum capacity) and the numbers of existing cars (from both existing and Local Plan houses) that would be expected to use the junction.
The spare capacity of each junction for cars is then turned into an estimate of the number of houses that would generate those cars. These houses are assumed to be situated within 4kms of the junction, and each house is assumed to be home to 1.27 workers and 2.33 people (both national average figures).
Thus, a spare capacity of an expressway junction for cars is turned into an estimate of the number of workers who might live in new expressway-unlocked houses near that junction. These numbers are shown in the call-outs for each junction on the map above.
We stress that the numbers of workers shown on the map are Highways England’s and not our own. The original graphic from Highways England’s Corridor Assessment Report (CAR) with these junction names and worker numbers (blue columns) are shown below for sub-option B1 (West of Oxford city) and B3 (East of the city).
We have guessed the approximate location of the routes and junctions on the map above, but we have not guessed the worker numbers. We read them off from these histograms in the CAR.
Taking Twyford as an example (map, histograms), Highways England calculated that the spare capacity of an expressway junction there could unlock a housing development for 46,000 workers, or a total population of 84,000 people, a settlement approximately twice the size of Banbury in Oxon, or bigger than Aylesbury and more than twice the size of Bletchley in Bucks.
The biggest settlement potential identified anywhere along the Arc is that proposed ‘East of Oakley’, with a worker population of 82,000 and therefore a total population of 150,000 people, almost the size of Oxford City.
The same workers and therefore total population (82,000/150,000) would also come from combining the two junctions South of Bicester (Corridor B1, ‘Wendlebury’ and ‘South of Bicester’) if the chosen route were to go West of Oxford.
The scale of these proposals is astounding. How could anyone imagine building an entirely new community the size of Oxford city’s in the next 30 years in what is currently rural Bucks, or in the already over-developed area south of Bicester?
Yet this is precisely what Highway’s England’s model predicts is possible. Their calculations show what the proposed expressway could enable.
Even if it were possible, would it be acceptable to the existing communities in the affected areas?
But these calculations fill junctions to maximum capacities. Surely they will build fewer houses than that?
The worker numbers shown in the map do indeed imagine that all spare junction capacity is taken up by the new expressway houses built around them.
But the maximum total number of all houses at all junctions along the expressway according to these calculations is only 360,000, way below the expressway-unlocked aspirational total of 553,000 houses (including the London commuter houses, this figure rises to 791,000 houses). Thus even if the expressway is built, and even if every expressway junction has around it a sufficient number of houses for it to reach its maximum capacity, there is still a shortfall of at least 193,000 houses (553,000 – 360,000) that cannot be accommodated anywhere along the expressway as currently planned. These additional houses will have to go elsewhere in the affected counties if the aspiration of one million homes is to be reached, and their residents and cars will increase congestion on the rest of each county’s roads.
The call-outs in the map also include figures for new jobs (orange columns in the histograms above) that, it is assumed, will be generated near each junction. These estimated job numbers come from a separate Highways England ‘job model’ that has, as one of its inputs, the number of workers available. Clearly this input is a major determinant of the predicted number of jobs, which are all remarkably similar to the locally available work-force!
We doubt that so many jobs will spring up locally, presumably from new businesses near each junction. The whole Arc region is being developed because of the high-tech industries along the Arc.These will operate as magnets for the new work-force; the workers will commute to the jobs rather than the jobs move to the workers.
If the expressway as such is cancelled, we expect alternative road improvement schemes to be put forward, of the sort suggested by England’s Economic Heartland (EEH), whose July 2020 decarbonisation document suggests a possible total of >860,000 new houses across the EEH region (similar to that of the Arc) by 2050.