Decision time for England’s biggest road project. What are the implications? (Part Two)

Introduction

In Part One last month, I reported on some of the 3640 documents which had been presented at the Lower Thames Crossing Public Examination of its Development Consent Order process during 2023, which finished on 20th December and in which I was closely involved. The plan then was that the Inspectors would by now be within sight of the end of writing their report to the Secretary of State for Transport, who would make a ‘final decision’ on what is the biggest scheme in the road programme this summer.

Of course, we are currently in a period of speculation about when the next General Election might be, and there must be – I guess – rather intense political interest in recalculating the political advantages to the Government of the timing and nature of its response to the Examining Authority’s as yet unknown advice.

This seems set to be a classically political heavy weight transport project decision, perhaps sitting alongside matters like those on the Third London airport, The Humber Bridge, and the go ahead (and then cancellation) of HS2. This is after all, the biggest single road scheme in the current programme. At best, the Lower Thames Crossing project must remain highly questionable in terms of its costs and benefits, value for money, and uncertainty of outcomes. I therefore don’t see how it would be sensible to rule out the possibility of a Judicial Review case in Court, in several different scenarios of what the Examining Authority’s Report says, and what the Secretary of State’s decision is. So a delay beyond the General Election seems possible, especially if there are intense financial pressures to save money on the most dubious of projects.

In this Part Two, I consider in some detail three key controversial issues considered at the Inquiry: a dispute about the traffic impacts at one major junction with ramifications for many others; the presentation of ‘agglomeration’ as the category of potential additional benefit which could offset the collapse of the expected benefits of time savings; and the continuing dilemma of how to treat the importance of climate change in the appraisal of specific road schemes. The column also touches on several other issues, of great importance, but which still need analysis in detail.

The Consequential effects on a Junction – an unresolved dispute

Orsett Cock, named after a former pub in the village of Orsett in Grays, Essex, is a junction on the A13. Thurrock Council had recently spent about £130m upgrading the junction to provide capacity for its emerging local plan, and it was included as part of the design of LTC providing the only connection north of the Thames. It will be particularly heavily affected by increases in traffic associated with the LTC, and became a cause celebre during the Examination due to an unresolved dispute about (a) who should pay for any necessary mitigation works, National Highways or Thurrock Council, and (b) unresolved technical arguments about the scale and intensity of traffic problems. Both questions are raised for a number of other critical intersections on both sides of the Thames, such as Bluebell Hill in Kent, but unlike Orsett Cock they are considered ‘wider network impacts’ that National Highways argued should not be its responsibility to address as part of the LTC application.

Usually, in the year or so before public examination, National Highways and various ‘official’ interested parties – local authorities, local businesses, people and organisations affected by compulsory purchase or other disruption – have extensive discussions to sort out ‘statements of common ground’. This enables the Examining Authority (which rarely includes members with detailed transport modelling experience) to treat such matters as given.

Things did not happen in that way in the examination of the LTC. There remained throughout the inquiry a very large - unprecedented - number of disputed forecasts and assessments especially related to the detailed calculations for traffic delays at some major intersections affected by the scheme (such as Orsett Cock), and the effects of the scheme on local roads especially affecting commercially important access to the two ports in the area and other activities. One source of this dispute was a difference between the outputs of the strategic model ‘LTAM’ owned by National Highways and a microsimulation model called ‘VISSIM’, widely used to simulate the build-up of queues at specific junctions. VISSIM takes demand predictions from LTAM, and often finds that these predictions simply will not get through specific junctions, without a build-up of excessive queues and much longer delays. LTAM, however, generally indicates that the delays will quickly enough settle down to an acceptable level.

One proposal, not agreed, was to use both types of model in harness, feeding back the results from VISSIM into LTAM and back to VISSIM, the cycle continuing until the forecast flows and traffic conditions were consistent. National Highways does not allow other agencies direct access to the LTAM model, so its agreement is necessary to do such interactive modelling. This they refused to countenance because it would require too much work and long delays beyond the time limit for the Examination (though this would not have been a problem if it had been carried out earlier). The dispute continued right up to the closing day of the Examination, and was left hanging unresolved. The main authority involved, Thurrock Council, submitted in evidence[1] its summary of the argument, of which a section is shown on the left, the black text being its summary of the NH argument and the red text its own.

It is important to stress that this is not a case of a battle between a technically competent scheme advocate and a technically naïve objector. (Though some irritation was caused by National Highways’ tendency to treat it in this way). Local Authorities have their own models, modelling teams, consultants, and of course a very much more detailed experience of the performance of their local networks.

The compensation or mitigation argument follows. National Highways continued to assert its position that expected adverse impacts are not sufficiently severe at any location on the wider network across Thurrock Borough Council, Essex County Council, Kent County Council and the London Borough of Havering, for it to be necessary to consider the mitigation of impacts as part of the DCO process.

Objectors pointed out an inherent implausibility in the claim that the largest ever road scheme, which increases traffic across the River Thames by 50%, had been designed so well that every junction functions without the need for additional work to mitigate the wider impact of the forecast additional traffic. NH argued that even if the Examining Authority were minded to disagree with their modelling evidence, it should be the role of the local authorities themselves – later - to resolve the induced harm to the local communities. The suitability and efficacy of the traffic modelling remains central. This is further exacerbated by the unwarranted determination of National Highways to assume that there is no induced traffic of light or heavy goods vehicles (as discussed in Part One of my contribution), which the Council contests, and makes the issue of the capacity of the network even more sensitive.

This has left a genuine problem for the Examining Authority, since reconciling the two approaches would not normally be part of their function, and the tight timetable for writing their recommendations did not have any provision for carrying out further technical work. They are, in effect, now required to draw conclusions from technically inconsistent forecasts. In such matters of technical knowledge and local financial responsibilities, as also of legal and financial rights, it cannot be assumed that one side of the argument is right by default. Note the critical claim in the graphic that without ‘common ground’, the ‘Council considers that the ExA does not have sufficient information to assess the scheme’. It is not at all clear what view the Examining Authority will take on this, but it is clear that they do have to take a view.

Amongst other things this experience calls into question the policy of National Highways not to allow anybody else access to their own model, but only whatever output they choose to release, on which they are not very open. Before the examination each local authority was only given some selected outputs of the National Highways model for their own area, and were required to sign a promise that they would not talk to each other to compare the outputs or make sense of cross boundary movements.

Quite apart from the question of how accurate or reliable the models are, there is an issue of ownership. My own wider view, for what it’s worth, is that all the National Highways modelling tools on which it depends have been developed at public expense, and should be treated as in a form of common ownership of all public bodies (and probably private bodies) affected by their use. Otherwise, the role of ‘Promotor’ and the role of ‘Appraiser’ become too entangled. This interpretative use does require appropriate expertise, of course, but there are plenty of modellers with experience of being employed by National Highways on modelling, and some at least would be keen to use their expertise in a less closed context. Meanwhile, the Examiners are confronted with a problem beyond their normal scope, and how this will pan out is a subject of close attention by the interested parties (and beyond). There are discussions of legal challenge on this point alone, and in any case DfT guidance should surely be updated to deal with this frequent recurrent issue.

Agglomeration – the Deus ex Machina for LTC

Another seminal issue is the matter of so-called ‘agglomeration effects’ and the contended additional benefits they bring to the scheme. Agglomeration is defined as a ‘wider economic effect’ based on the idea that individuals and firms derive productivity benefits from locating in close proximity to other individuals and firms, and this additional benefit is counted an externality, in addition to the direct benefit to themselves, because by locating in such an area they are also bringing economic benefits to other individuals and firms, and so a wider societal gain can be applied.

The DfT advice is contained in TAG Unit A2.4 Appraisal of Productivity Impacts[2] which was published in 2016. It uses source references mostly of published work in 2006-2009, with little more recent research and especially key weakness in empirical analyses to test whether road improvements actually have delivered these promises. Agglomeration is indeed still officially counted as a less well-established idea, to be shown separately in the overall Cost-Benefit calculations, and with a number of caveats about its reliability and interpretation.

I would emphasise four caveats, in principle. The first, on displacement, is set out in TAG, the DfT states

“2.2.6. Key to any assessment of agglomeration is displacement; in other words the extent to which changes in local productivity are additional at the national level. Displacement reflects the extent to which an increase in economic activity in one location is partially or fully offset by reductions elsewhere. The default assumption in transport appraisal is the full displacement of employment impacts resulting from transport investment (see TAG Unit A2.3). That is, unless there is evidence of a net national impact of a transport scheme on employment in the UK, it should be assumed that the net job impact is zero”.

The modelling restriction that there can be no induced traffic for goods vehicles, and little for cars, must suggest that additional jobs are few or unlikely. If there is relocation (which actually is not allowed for in the modelling) then it must be from somewhere else, which is, by definition, then less agglomerated.

Second, it is rather obvious that agglomeration benefits cannot be infinitely extended. At some point attraction of more activity to an area will also produce disbenefits, of overcrowding, noise, pollution, damage to common property, other stresses on infrastructure, and a need to provide extra social resources for handling waste or pollution. These are not allowed for.

Third, thinking on more recent economic developments has tended to focus on ways in which physical proximity is becoming less important, not more, because of digital connectivity, social media and on-line communications. It is often argued that Intellectual proximity is becoming relatively more important than physical proximity, though this is likely to vary greatly between sectors.

Fourth, improvement of a part of the road network in one area, in the general case, theoretically produces an incentive for relocation not towards the improvement, but in the opposite direction, as this is the most efficient way of expanding the catchment area for any business. In that case, we must also consider the external costs of sprawl, which have been an increasing problem throughout the period of suburban development.

However, none of these four caveats were given weight in the LTC analysis which applied agglomeration benefits to the overall Benefit Cost Ratio (BCR) equation. The calculations carried out (which, it has to be said, are of a complexity and obscurity which few if any of the participants claimed fully to understand), were straightforward only in their effect, which was simply that a large – very large – quantity of benefits would be produced, enough to rescue the project from what otherwise would not remotely give acceptable standards of value for money. ‘Wider Economic Benefits’, (of which agglomeration comprised 90%), were the largest single element of LTC’s economic case, comprising 46% of all net scheme benefits. It was only through the inclusion of these benefits that the Benefit Cost Ratio gets even to 1. Without them, the scheme makes a large net economic loss.

So the main concern – repeatedly raised in written submissions, but almost invisible in debate – is the size of this reported additional effect, the scale of which dwarfs the traditional concerns of benefits to road users or relief of congestion. The uncertain calculations, and the fact that they were out of line with the results of other studies of the effects of including agglomeration on appraisal, does not give confidence that this would be the suitable source to tip the scales.

By way of further exploration, Table 1, which I have constructed from a report by Aecom (2013) Review of Lower Thames Crossing Options: Final Review Report[3], published by the Department for Transport, consists of a comparison of four different design and location options, and three different cases (for a bridge, immersed tunnel or bored tunnel), for which rather detailed assessment summary reports were published. The pattern is very clear - in all cases the calculated agglomeration benefit was substantially smaller than the expected travel time savings, ranging from 22% to 46%. Including it raised the claimed overall BCR, but with one exception was not crucial to the outcome.

The last column shows the figures for LTC claimed at the Examination, with the wider economic benefits being the largest single category of benefit overall, in which agglomeration was 66% of the claimed value of time savings, and essential for the scheme, much greater than in the options review.

So how, we must surely ask, between 2013 and 2022, at the same time as the value of estimated time savings dropped, did the reported agglomeration benefit grow so unexpectedly? After all, the two values are both intrinsically related to accessibility, so much so that there is a serious empirical difficulty in separating direct value of time benefits from wider economic benefits. I haven’t been able to do a complete literature search of all other such calculations used in projects, but with the assistance of advice from James Laird (whose own work with Tvetter[4] and Aalan[5] are important recent contributions to this field), and some other work cited in the LTC Examination, a fairly clear picture emerges. All other studies calculate a substantially lower agglomeration benefit than that used in the LTC calculations:

• For HS2 the wider economic benefits pushed the BCR from 1.9 to 2.5. It’s also intriguing that a review of wider economic benefits for HS2, included

• The A303 Stonehenge Business Case [6] of 2018 had wider economic benefits of just 3% of net scheme benefits.

• The Eddington Review of 2006 [7] wider economic benefits as a whole (not only agglomeration) to raise BCRs from about 2.5 to about 3.3 for some urban networks, from 5.6 to 6 for some international gateways with surface access, and a much smaller uplift of about 0.1 to some inter-urban corridors.

• The London Crossrail scheme – thought to be the exactly the sort of urban project which would be particularly successful in generating agglomeration benefits-calculated time savings worth £12.8 billion, and agglomeration benefits of £3.1 billion, 24% of the time benefits, very similar to the earlier LTC figures I have referred to above.

In these schemes the wider economic benefits just pushed the BCR further above a level of 1, and were not critical to the business case in the same way as they are for LTC.

Clearly in a sense LTC ‘needed’ the figure to be higher. But that does not explain why it is out of line with other studies. James Laird suggests that there might be an established random, unpredictable error that arises through a spatial aggregation process, which had been found in Norwegian analyses using similar methods.

All the above comparisons are ex ante expectation of agglomeration benefits, i.e. the theoretical prediction before the event. Ex post analysis to see whether there actually had been economic benefits is exceptionally difficult. One study is by Sloman, Hopkinson and Taylor (2017) The Impacts of Road Projects in England, used National Highways own Post-Project Evaluation (POPE) reports of short term effects of over 80 road schemes and longer term impacts of four (the A34 Newbury Bypass, M65 Blackburn Southern Bypass, A46 Newark–Lincoln dualling and A120 Stansted to Braintree dualling[8]). Their conclusions on economic impacts were as follows:

“Of 25 road schemes justified on the basis that they would benefit the local economy, only five had any evidence of any economic effects. Even for these five, the economic effects may have arisen from changes incidental to the road scheme, or involved development in an inappropriate location, or involved changes that were as likely to suck money out of the local area as to bring it in.

Where a road scheme was justified on the basis that it would support regeneration of an area with a struggling economy, it was common for economic development following completion of the road scheme to be slower than expected, or not to materialise at all, or to be of a type which offered little benefit to the area concerned.

Where a road scheme was justified on the basis that it was needed to cater for current and future traffic in a ‘pressure cooker’ area with a buoyant economy, it was common for the scheme to be followed by much development in car-dependent locations, causing rapid traffic growth and congestion on both the road scheme and the pre-existing road network. Some road schemes were justified on the basis that by reducing journey times, they would increase the number of jobs that were accessible to local people, or increase the potential workforce able to access major employment sites, or create thousands of new jobs. There was no evidence of measurable economic benefit from these schemes.”

Here again, this matter of claimed agglomeration benefits leaves a serious issue for the Examining Authority. How are they to assess the reliability of these most theoretically complex calculations, defined as ‘highly uncertain’, strongly challenged, unprecedented in scale, out of line with other experience, and absolutely essential for the economic viability of the project? And whatever their judgement, there will then remain a crucial difficulty for how the Civil Servants at the DfT, who wrote the methodological guidance, advise the Secretary of State in enabling his final decision to be robust, defensible and wise.

Accounting for the Scheme’s Carbon and Climate Change impacts

The third, existential, issue I want to raise relating to the justification or otherwise of the LTC is examination of the effects of specific road schemes on carbon emissions - a highly controversial aspect of recent discussions about climate change. To date, the Government, and National Highways, have mostly relied on the observation that the effects of any one scheme will inherently be a small proportion of the total emissions of carbon from all UK purposes and sources: if action is deemed satisfactory at national level to address the UK overall contribution, specific schemes need not be rejected on the grounds of carbon. Objectors have argued against this with the reminder that transport is the largest carbon emitting sector, with a rate of change not in line with a trajectory to meet climate concerns and that therefore transport schemes have a specific and pivotal responsibility. There is also an unresolved argument about whether current Government funding and policy commitments have moved away from the 2022 decarbonisation strategy, and therefore realisation of the targets. In any case their prospective effects on levels of traffic growth are not included in the DfT’s Common Analytical Scenarios whose analysis was discussed in Part One of this contribution.

Critics at the Examination argued that the case as presented for the LTC does not allow the Government to meet their requirements of the Paris Agreement (Article 4) for transparency in emission reporting. This lack of transparency in measuring, reporting and verification relates to the: comparative emission boundaries set within the project carbon assessment in comparison against the total national emission boundaries; and the difference in greenhouse gas calculation methodologies between the project emissions and those developed for National Emissions Budgets, the National Atmospheric Emissions Inventory and the Climate Change Committee’s Carbon Budgets.

If there is less overall traffic on the road due to successful implementation of traffic-related aspects of transport decarbonisation, the DCO has not assessed the impacts of this on the economic case for the scheme.

It was argued that the LTC project disregarded best practice guidance Assessing Greenhouse Gas Emissions and Evaluating their Significance (Institute of Environmental Management and Assessment IEMA, 2022) and has not followed the internationally recognised methodology for appraising carbon emissions Greenhouse Gas Protocol (GHG Protocol for Project Accounting, World Resources Institute 2003), especially relating to setting boundaries for assessment and the use of industry specific guidance for greenhouse gas reporting. The Environmental Statement asserts that the project is compatible with the budgeted science-based 1.5C trajectory, but this is contested.

It is not clear that any of the discussion on this topic had traction in the DCO proceedings, and nor is it easy to see whether the Examining Authority will perceive that it has a particular authority or role on the Climate Change/Decarbonisation question. In recent years it has been a significant element is proceedings at various levels in the Courts, rather than DCO Examinations, in which these questions have been rehearsed, with mixed results as to which elements are judged legally relevant.

A new feature in the discussion is the question of what role Local Authorities should have over transport effects on carbon in their own area, and what verification programme, if any, should be carried out to monitor success. A related question, also unresolved, is whether there is an effective local authority responsibility to contribute to carbon reduction, and if so, does it provide an arguable dimension to the consideration of a scheme affecting their area like LTC. This also was raised in the Examination, but again with no clarity about whether it had traction. It remains politically very important overall, and any actual decision taken on LTC must have an impact on the subsequent discussion, so it is likely that that argument will continue whatever the outcome.

The Government’s own view on this question may have evolved significantly over the last two years, especially in a letter[9] from DfT to all Sub-national Transport Bodies, sent on 18th January 2022. It asked them to reconsider their road schemes, including

“whether the scheme is likely to make carbon worse and lead to lower VFM, especially now the cost of carbon has been increased substantially... it is likely that we will not have sufficient funding to continue to fund all the schemes currently in the programme to the current scale or timing. In addition, since the programme was set up in 2019 there have been changes to Government policy around transport investment, analytical requirements especially on carbon impacts, the impact of new forecasts and of course the effects of Covid on delivery and future demand. It is therefore right that we now take the opportunity to review the programme…”.

The letter also said ‘We are writing in similar terms to all local authorities with schemes currently in the programme.’ But I believe those ‘similar terms’ letters were never actually sent – one of the loose ends in the DfT’s evolution of policy on decarbonisation.

One particularly important new feature of the discussion is that even if consistency with Climate Change forecasts and Policy turn out not to be considered relevant to the Examiners’ recommendations, the actual cost of carbon – for the first time, I think – emerged as very material to the scheme’s value for money calculations. The figure for the economic cost in Greenhouse Gases overall, using the current recommended ‘central’ values, totalled a figure of £527.7 million – higher than the stated value of each of the following other separate items: changes in travel time variability, accidents, construction and maintenance delays, tax revenues, land acquisition, or operation, maintenance and renewal costs. This does mean that in the economic appraisal carbon does now ‘count’ as a significant effect, even if its effect on climate change is still treated as insignificant. At the high recommended value of carbon, and taking account of the recent decision to include the value of VAT as well, close to £1 billion would be included in the LTC’s project’s balance sheet. I count this as a step forward, subject of course to the models’ ability to calculate the actual amount of carbon reliably.

Some Other issues

Beyond these three critical areas of contention I have explored in detail here, there is not space to make a similar assessment of a number of other important issues. These include:

• longer term impacts of the Covid Pandemic on transport activity;

• revised official economic growth estimates following financial crisis and estimated effects of Brexit;

• vulnerability to continued climate change, in general and in the Thames Corridor in particular;

• potential impacts of and on declared Government policy – and possible changes in that policy - on walking, cycling, public transport, vehicle occupancy, and land use planning to reduce road traffic;

• Inadequate treatment of alternatives to LTC, including modal and demand; management alternatives, especially in the context of potential lower traffic growth;

• potential effects of changes in vehicle taxation which would reduce the growth in EV traffic;

• Cost of additional highway schemes needed to mitigate the impact of LTC on the wider transport network;

• Biodiversity and Ancient Woodland effects;

• calculation of a value of improved reliability of travel times (by comparison with what might happen if the scheme does not go ahead);

• any further increase in cost, for which there Is now a much lower headroom to allow for cost increases than there was at the time of the original calculations.

Clearly responses to what the Examining Authority has to say on all these matters will be crucial, and I hope interested readers may want to take up discussion of any of these issues in more detail, and indeed to respond to the points I have made. Such responses can be readily made as written contributions in the discussion platform provided by the TAPAS online Network on which my contribution appears[10].

The positions taken by National Highways as proponent of the project and by Thurrock Council as a principal opponent are certainly sharply contrasting as the graphics below illustrate.

This brings me to my own conclusions from the two contributions I have now made about the Lower Thames Crossing and its appraisal and justification, which I present below.

Conclusions - Unstable numbers and unanswered questions

In Part One of my contribution, I noted the very high Benefit Cost results which had been reported at an earlier stage of the Lower Thames Crossing proposition, when National Highways were bidding for the scheme’s inclusion in its infrastructure programme. These indeed continued even up to 2018, when a BCR of 3.4 was seriously suggested. By 2020 the BCR figures were only half of this, and even less by the time the Examination opened, since then even further eroded by later DfT changes in assumptions, methods and data.

These changing figures in themselves do not give great confidence in the process of economic assessment, and they now cast great doubt on whether the project provides acceptable value for money. In particular, there are several major fragilities:

• Either, if demand is lower than assumed, then the net present value is likely to be negative, i.e. it makes a loss to the economy as a whole. Or,

• If demand is higher, then there is the prospect of a very short period of congestion relief, followed by increasingly intense traffic problems, engendering a serious issue of public confidence in transport professionals, and Government’s, ability to deliver on what will be seen as promises to reduce congestion.

In either case, the BCRs remain firmly in the ‘low’ category, at best, and stray into the ‘poor’ category (i.e. benefits are less than costs) in some credible circumstances.

Concerning research, I concluded that the treatment of induced responses by goods vehicles within the appraisal was already inconsistent with substantial empirical and theoretical research, and with the objectives of the project. If, as was claimed, there are no suitable modelling approaches available to allow for induced traffic responses affecting light and heavy goods vehicles, there is an urgent need for a model development programme to fill this gap, this sensibly being a DfT responsibility rather than a National Highways one.

From this Part Two analysis and reflection, I now suggest the following critical matters requiring detailed further attention :

• There should be a change in practice for modelling the effects of major road projects on local roads and intersections, with allowance for the interaction of the detailed simulation of local stress points and network-wide models allowing for all the major elements of demand responses over a wider area and time, jointly controlled by both national and local highways agencies, with independent and combined direct access to both levels of modelling.

• The treatment of wider economic effects, especially agglomeration, needs much better verification of the credibility of orders of magnitude, consistency with the assumptions in other parts of the appraisal, and much greater attention to empirical research on the actual outcomes of transport interventions on measurable and demonstrable local and national economic impacts.

• Carbon emissions and climate change are clearly now accepted as issues of great importance, but the relevance of that for specific schemes – and indeed programmes - still remains argumentative and unclearly defined, in a way which is difficult to resolve locally, if it is unresolved nationally. And the implications of significantly greater climate change than hoped are still not being seriously confronted.

All these issues will either be addressed by the Examining Authority, or left unaddressed, and in either case present serious implications which are yet to be clarified for both this scheme, and the final decision on it, and others. I hope my work on this contribution may help to provide a checklist of how to read the Authority’s report and recommendations, both in its extent and comprehensiveness, and in the formal judgements made. I am sure a great number of people will be watching this with great interest, including, no doubt, the Civil Servants advising the Secretary of State on his final decision.

Underpinning all this is a fundamental question whose time, surely, has now come. Can it be right for the main Promoter of any scheme to have such a dominant position in control of the information and modelling to appraise it?

The objectives set for National Highways – to deliver a road programme – do not comfortably encourage the style of independent, thoughtful, critical assessment which could ever lead to the conclusion that part of the programme is unjustified. These preparatory and advocacy activities deploy very considerable public resources, and should be open to scrutiny, investigation, and control – both for reasons of the principles of public administration, and because there is little chance otherwise of reaching consensus on such controversial proposals. At present there is no agency with the resources, staffing, terms of reference and culture to be in charge of genuinely independent scheme appraisal. Would it not be possible to set one up?

It is really unfortunate that the case being made for the biggest road scheme in the current programme should also be one which is so weak analytically. The unbelievably huge number of words and reports has not been matched by corresponding quality. But if the fragility exposed results in a serious re-examination of process and content, it could lead to a worthwhile outcome.

This is a highly questionable, very expensive, project, at a time of significant constraint on resources, and in competition with very many transport investments and policies with much better financial, environmental, quality of life, and efficiency results. It is perhaps unavoidable that there will be feelings that too much has already been spent to back away, and the project is ‘too big to fail’. This would be, in my view, a mistake.

The first part of Professor Goodwin’s Lower Thames Crossing analysis is available here: https://tapas.network/49/goodwin.php

References and Links

1. https://infrastructure.planninginspectorate.gov.uk/wp-content/ipc/uploads/projects/TR010032/TR010032-005553-Thurrock%20Council%20-%20Post-event%20submissions,%20including%20written%20submission%20of%20oral%20comments%20made%20at%20the%20hearings%20held%2020%20to%2028%20Nov%202023%20(if%20held).pdf

2. https://assets.publishing.service.gov.uk/media/5a804ff5e5274a2e87db9176/webtag-productivity-impacts-tag-unit-a24.pdf

3. Review of Lower Thames Crossing Options: Final Review Report https://assets.publishing.service.gov.uk/media/5a748341e5274a7f99028c85/final-review-report.pdf

4. https://www.sciencedirect.com/science/article/pii/S2213624X20301103

5. (TVETER, E., J.J. LAIRD and P. AALEN (2022) Spatial aggregation error and agglomeration benefits from transport improvements. Transportation Research Part A, Vol. 164, Oct 2022, pp257-269. https://www.sciencedirect.com/science/article/pii/S0965856422002002).

6. https://infrastructure.planninginspectorate.gov.uk/wp-content/ipc/uploads/projects/TR010025/TR010025-001183-Highways%20England%20-%20Contingent%20Valuation%20Survey.pdf
   

7. https://webarchive.nationalarchives.gov.uk/ukgwa/20081230093524/http:/www.dft.gov.uk/about/strategy/transportstrategy/eddingtonstudy/ Figure 1.5, Volume 3

8. The Impact of Road Projects in England, https://www.cpre.org.uk/wp-content/uploads/2019/11/TfQLZ-ZTheZImpactZofZRoadZProjectsZinZEnglandZ2017.pdf

9. It is unclear whether the letter was actually ‘published’ by the DfT, but a copy was published by ‘Transport for the South East at https://transportforthesoutheast.org.uk/app/uploads/Shadow_Partnership_Board/20220613-PB-Item-15-MRN-and-LLM-Schemes-Update-Report-plus-appendices.pdf

10. Decision time for England’s biggest road project. What are the implications? (Part One)