Rethinking Zero Carbon Urban Form in the Arc

The Oxford Cambridge Arc Project gives us an ideal opportunity to rethink appropriate urban forms of Garden Communities.

From previous government announcements on the Arc the predominant thinking seems to be an approach of having a ‘few big blobs’ of development along a rail corridor. Once you start to adapt evaluation methodologies to zero carbon reality it is clear that this is no longer appropriate – let me explain.

The two key drivers in evaluation methodologies are as follows:

  1. Regional Economic models which evaluate urban and industrial economies of aggregation;
  2. Cost Benefit Ratio evaluation of transport options.

The first is indisputable, once you accept that the urban area is a functional city region not just a single blob.

The second is problematic once you consider the fixed constraint that zero carbon planning provides.

Look at rail. New rail has a high upfront fixed cost (track, land etc.) and a moderate variable cost per passenger (trains, labour) and an almost zero marginal cost once you have the track and trains. Which is why it makes sense once you have the track and trains to subsidise the journey.

However CBA is based on the evaluation of the economic cost of time. The more trains stop the longer it takes to get to a destination. This means that the CBR of an express limited stop service will always be lower than a short stop commuter service. You add more passengers as you increase capacity but the benefit in terms of time per passenger goes down, so the CBR is always lower. This is clearly influential in the planning of East West Rail for example, where across the whole length of the project it will only have two new stations and net less stations than at present. Options such as four tracking will always have a lower CBR than dual tracking, diesal will always have a higher CBR than electrified services.

The problem with CBA often is calculating the counterfactual ‘do nothing’ scenario. Once you exclude positive carbon as a policy option this transforms the decision space. The cost of global warming is incalculable. Therefore CBR should only be applied to alternative zero or negative carbon options.

Applying this principle to new settlement/rail options you would have to exclude express service/big blob new settlements. The housing at the edge of the settlement would be car based and the time taken for interchange too high. Options need to be based around high frequency, high capacity short stop services around routes with high density development within walking distance of stations, like classic train and streetcar suburbs.

This is not to say you should have ridiculously short distances between stations, such as the current Marston Vale pattern sensibly proposed for rationalisation. Dutch planning teaches us that if you have good cycle infrastructure to stations you can extend distances between stations. On Marston Vale for Example you could have high density development around fewer stations and employment areas in between, which is certainly not what you find in current local plan proposals.

Once you understand this you gravitate towards a polycentric urban form in a string of pearls arrangement. You manage the higher frequency services through a combination of interleaved stopping services, passing loops and ideally 4 tracking. Also as recent reforms to the Green Book indicate CBR is not the only criteria, you also need o consider policy objectives such as the ability to move people in a zero carbon network. I often find a ‘headway obession’ (headway is time to turn around trians), in uk transport planning, which is haven’t found for example working with the Japanese, where ability to move the masses is always the priority.

This polycentric urban form was of course advocated by Fred Pooley in his pre development corporation plan for Milton Keynes. Set aside the silly monorails it is still a good pln, the best ever unbuilt plan in the UK. So new settlements in the Arc need to be Polycentric, between 50-150,000 in population based around networks in multiple stops. By contrast all we seem to have in the Arc is two big blobs at Tempsford and North of Cambourne.

Indeed once you start looking at CBR for rail and BRT in the ARC new options open up. It would even be worthwhile I think to split the central section South of Sandy, one route North and one Route South of the Sandy Hills both converging at Shenford South of Cambridge, the reason being that this opens up large development opportunities in the southern corridor, plans for which I have published before.

10,000 New Homes at North Cambourne ‘identified in emerging Greater Cambridge Local Plan’

A bit of a blunder in the east-west rail new consultation regarding the North of Cambourne Station and route option.

We expect that new homes and communities could be built to the north of Cambourne without causing Papworth Everard, Knapwell and Elsworth to join up, and a site in this area is already identified in the emerging Greater Cambridge Local Plan. There are also fewer heritage assets and areas of woodland and habitat in the area to the north of Cambourne (compared to South of Cambourne)

Trouble is it is only so far one of many call for sites submissions. How often do planners have to explain cal for sites is not a raft plan proposal.

Below is the call for sites submission for 10,000 Homes for the site by Savills

The trouble is we know work is advanced on options for the Greater Cambridge Plan, including options for several corridors not just of East-West Rail but Cambridge Autonomous Metro CAM, which of course is spelt BUS. Of course North of Cambridge is an option in that document.

So this option has slipped out.

There is also the site land to the West of Scotland Road Dry Draydon supported by the Greater Cambridge Mayor for 8,000 homes.

In terms of other options to be considered in the ARC framework the only other one clearly flagged is either Tempsford or South of St Neots depending on which route is chosen. They are not far apart but the Tempsford Route avoids A48 road severance between the station and a Tempsford new Settlement. So where are the other two new communities along the route already flagged up. Winslow appears as a station on the map but is otherwise not mentioned, Calvert is not mentioned though it would be along the extension of the route to Aylesbury. Note however that the leaks referred only to 4 in the central section – MK to Cambridge. So that could include South West of Cambridge.

These hardly add up to a million homes, they hardly add up to 50,000 if that. Of course there are sites that could be served by new CAM routes such as to Haverhill, however we are unlikely to see a bold ambition of new communities of over 50,000, which Homes England said they favoured, served by radical public transport options running every 4 minutes (which the NIC have said privately they favour). The weak ambition and lack of dramatic public transport options paid for by land value uplift mean the emerging arc framework is becomining a damp squib, failing to promote settlements of a scale, form, density and accessibility to meet zero carbon objectives, what we will get is bloated sprawl in car dependent villages, as we have got in the Arc for the last 40 years.

New East-West Rail Route Options Consultation Begins Today


What a north south zigzag around Cambridge

Cambridge Independent

The East West Rail Company has unveiled five potential routes the new line could take into Cambridge – including proposals for a huge flyover in the South Cambridgeshire countryside.

The routes are revealed as the latest phase of public consultation on the £5billion line linking Oxford and Cambridge, via Milton Keynes and Bedford, is launched.

The consultation documents acknowledge an “emerging preference” for the new station at Cambourne to be built to the north of the town, rather than the initial suggestion of placing it in the south, where residents, the town council and the Wildlife Trust feared it would have devastated the Country Park.

But other aspects will raise major questions for communities along the proposed routes.

It remains in favour of a southern approach to Cambridge due to a number of major engineering challenges with a northern approach.

And this means a large flyover is proposed south of Harston to cross the River Cam, the A10 and the existing railway line – as exclusively revealed in this week’s Cambridge Independent.

A deep cutting through a hill south of Haslingfield is also part of the plans.

The East West Rail Company, which hopes to complete the new line by the end of the decade, is seeking feedback on the five proposed route alignments, connecting existing stations in Bedford and Cambridge via new stations in the area around Sandy and St Neots and at Cambourne.

From there, the rail company – which highlights two of the five schemes as its favoured routes – still prefers a route southwards into a stop at Cambridge South station to serve the fast-growing Cambridge Biomedical Campus.

This is the first time the entire route has been drawn together in a single consultation.

The East West Rail company said there were six key areas of focus for the consultation:

  • How Oxford Station and its supporting infrastructure could be improved – including Oxford Parkway and Bicester Village stations
  • Options for avoiding lengthy periods of delay at the London Road level crossing, Bicester
  • How to ensure that communities around Bletchley and the Marston Vale Line would get the most from significant investment in their railway line
  • Options for new stations at Bedford and Bedford St Johns and their supporting infrastructure
  • Five route alignment options for the section of East West Rail between Bedford and Cambridge, including an emerging preference for a station at Cambourne North
  • Plans for improving customer experience through better station design and more timely travel information

The company has also presented developing plans for a new Bedford St Johns Station and a complete redevelopment of Bedford Station. Direct journeys from Bedford to Cambridge will take 35 minutes.

Sue Roberts Fails in Bid to Overturn her Own South Oxfordshire Local Plan – and has to pay costs

Oxford Mail

A GRASSROOTS group, which took a district council in Oxfordshire to court over a hated housing plan, has had its application rejected.

South Oxfordshire District Council confirmed that The Honourable Mr Justice Dove has refused the application by Bioabundance CIC for permission to proceed with an application for judicial review against the council’s decision to adopt the highly-controversial Local Plan 2035, which sets out where 30,000 homes can be built in the area.

Even more, in refusing the application, the judge ordered Bioabundance, founded by South Oxfordshire district councillor Sue Roberts, to pay the council’s costs.

The company now has a week to ask for this decision to be overturned.

A spokesperson for the local authority commented: “We are pleased with this decision and that the court has supported the democratic decision making processes within the council.”

In January, Bioabundance challenged the South Oxfordshire Local Plan after the Government ordered the council to adopt it. The environmental group claimed the Local Plan failed to comply with the Climate Change Act 2008 because of the amount of homes planned for the district, with many set to be built on Green Belt land.

Government to Oxfordshire – We are Punishing You for Slow Plan Making – So Go Away and Deliver 36,000 less houses

In a government statement on the 25th of March the Planning minister removed the special ‘3 year housing land supply’ concession to Oxfordshire.

In March 2017 the Government committed to the Oxfordshire Housing and Growth Deal (the deal), to support ambitious plans to deliver 100,000 homes by 2031. The deal committed to an Oxfordshire-wide Joint Statutory Spatial Plan to be adopted by 2021, and to be supported by £215 million of funding to help deliver more affordable housing and infrastructure improvements to support sustainable development across the county.

As part of the deal, to support this strategic approach to supporting housing delivery through joint working, Oxfordshire was granted flexibility from the National Planning Policy Framework policy on maintaining a five year housing land supply. Since 2018, Oxfordshire have had to provide proof of a three-year land supply for planning purposes. This has worked to support the delivery of the local plans for the area and ensure that the local authorities could focus their efforts on their Joint Spatial Strategy.

This flexibility way laid out by Secretary of State at the time the Rt Hon James Brokenshire MP in a Written Ministerial Statement on 12 September 2018 – in a new tab).

Since 2018, Oxfordshire have not finalised and adopted their Joint Statutory Spatial Plan. Therefore, in the best interests of housing delivery in the region, my Department have extended the time afforded to Oxfordshire for the delivery of this plan to 2023. This extension however will not be subject to the original land supply flexibilities. From today, Oxfordshire will need to maintain a five year housing land supply in accordance with the National Planning Policy Framework.

The growth deal simply commits to local plan levels of growth and includes no element of overspill from ‘land constrained’ areas such as London as per the NIC Arc report. It is based on a 2014 SHMA that included elements for past underprovision and a ‘jobs led’ assumption to reduce the jobs/housing imbalence in the area. Hence it was well in excess of the standard method. The latest standard method only works out at around 63,000 houses 2011-2031 according to Nat Lit . It actually suggests a slight fall for Cherwell as healthy completions at Banbury and Bicester Garden Town have pushed down completions.

The last sentence has been interpreted by Turleys as implying going forward the standard method replaces the growth deal.

Local planning authorities should identify and update annually a supply of specific deliverable sites sufficient to provide a minimum of five years’ worth of housing against their housing requirement set out in adopted strategic policies, or against their local housing need where the strategic policies are more than five years old

By the way there is an error in the NPPG which claculates it in a different and incompatible way.

The local plan’s in Oxfordshire are adopted or about to be so. However Cherwells is now more than 5 years old. So it immediately drops down from around 1,200 to around 700 dpa.

Turley were right to highlight this and it is clear the Ministry made a blundering error here. All the remaining local authorities in Oxfordshire have to do is run down the clock, let their local plans get more than 5 years out of date and reduce their housing requirements by 1/3rd. Sue Cooper and the other South Oxfordshire Avocado Nimbys must be rubbing their hands in glee.

This is an enormous own goal by the government. It complicates the South Oxfordshire JR. It complicates the Oxfordshito twice the re plan, with the Southern Oxfordshire Authorities saying we should we stick to twice the rate of the North.

It also illustrates how it is a nonsense to apply the standard method to growth areas, for three reasons.

Firstly as they aim to stop housing shortages restricting firms growth they have to be jobs led.

Secondly as you start to build at scale your affordability ratio goes down and you have to build less. So the injunction in NPPG that it takes account of backlogs no longer applies.

Finally when the 2018 HH projections cam out the government stated that the ARC would help take up the slack between the national total of the standard method and the 300,000/annum manifesto target. Is this no longer the case, are the 35% uplift authorities supposed to take up the slack now?

Finally the new census. The new national datasets of population created for covid purposes imply major under enumeration in Oxford and Cambridge. This will be no surprise to many authorities. I for example stayed in a hotel on census night and saw nothing of a census form. As few students will have been in either city on census night the 2020 census will be useless for standard method purposes. The ministry will have to shift I think to using the much more accurate NHS figures, indeed the ONS has a project to explore this after 2021, (known as the Danish methd) and for the ARC use those figures combined with an economic growth model projection to calculate an up to date ‘jobs led’ housing number. The standard method just wont cut it.

Bedfordshire Arc Options

Continuing this series looking at potential options for strategic growth locations in the forthcoming Ox-MK-CAM framework we turn to Bedfordshire.

The South of Bedfordshire is fairly easily dealt with. There was a rather good joint local plan of Luton and South Beds that has shaped what goes in the local plans now. This included growth to the North and East of Luton and around Houghton Regis South of an A5 M1 link Road. Growth East of Luton is included in the draft North Herts local plan.

This broadly represents the natural limits of Luton and Dunstable constrained as they are by the Chilterns AONB and Sutton Hooe. Therefore, because it is such a large town, there will need to be major overspill to Central and Northern Bedfordshire. Development north of the new link road would be car based and not sustinable.

Most of the rest of Central Bedfordshire, south of Marston Vale, is composed of very small towns which are not good candidates for strategic growth, with two exceptions.

The first is around Biggleswade which has some growth proposed but could take far more. It all depends on the route of East West Rail. If as is likely a new station is proposed between Sandy and Biggleswade there could be growth north and east if Biggleswade (avoiding the common) and South of Sandy.

The other big candidate is Henlow Barracks, recently declared surplus and now in the draft local plan. It could be extended further east next to Arlesely station. Henlow Camp developed alone would be isolated and car based. A joined up masterplan with BRT connections to Arlesley station would transform it to one of the best candidates for strategic growth in the Arc.

Turning to Marston Vale. This has the problem of being split between Central Beds and Bedford. It comprises worked out brickfields and is the largest brownfield area by far in the Arc. There is a plan to connect the Grand Union Canal to the Ouse with a canal and the Forest of Marston Vale projects plan afforestation in those areas unsuitable for development because of flood risk. There were proposals for an Ecotown in the area, effectively a linear city linked by the two rail lines passing through the vale, but local authorities resisted it, part from the large Wixhams site south of Bedford. The main sites in Central Beds are now in the local plan. Some sites in Bedford area, at Stewartby and some employments sites to the West, which are owned by a large Chinese investor. Those further East are not. Rather Bedford laid all of their bets on a new settlement at Sharnbrook Station next to the Colworth Park Research Park (the former Unilever Research Park). This made a lot of sense. The problem was proximity of the Santa Pod Raceway at former RAF Podington. The sensible thing to do would have been for Homes England to CPO the former RAF base and move Santa Pod East to the former Bedford Aerodrome, much further away from houses, enabling a much larger strategic site.

With 5,000 houses missing from their local plan Bedford had the choice of developing to the South of Bedford. Local firm Phillips has put forward a masterplan for the area but the response of Bedford was, well its just too hard, were developing a lot South of Bedford anyway, we will look at in the next local plan. The truth I suspect was that they were stalling because of the uncertainty over the route of East West Rail, will it have a station at Wixhams or pass through Bedford Midland to the East (which requires demolition of small retail warehouse park) or pass along the East Coast mainline and then veer east North of Bedford. It looks like the third is being pursued which is the very worst – and by far the longest – option. Sharing track with the east coast mainline will radically throttle capacity, preventing the sub-5 minute headway originally proposed (requiring Japanese style digital signalling) and essential to forming short stop zero carbon new settlements along East West Rail in a string of pearls fashion. Also Bedford is woefully underesourced

Bedford itself is now completing expansion to the South East to the edge of a bypass whose alignments was first plotted in the 1930s. Another option for Bedford is to develop a new settlement or settlements to the West beyond the Great Ouse Valley along the alignment of the Former Bedford to Northampton Railway. The restoration of this to rail is now formally on the table, though I think mid term as BRT would be much more practical. This is exciting as it could drive zero carbon growth South East of Northampton, west of Bedford and around Oundle. I evan did a sketch masterplan for the area West of Bedford a couple of years ago and grasping for a name called it Radcliffeville – after local hero Paula Radcliffe.

The final option is either North West of Bedford, which is very rural with poor roads, or South East, East of the Cardington Hangers. depending on the route of East West Rail. The latter is by far the best and could utilise part of a former railway line that passes through Cardington.