Tel/fax: 020 8333 2152
17 August 2022
Labour group, London Assembly
cc: Labour group members
Thank you for your letter of 10 August, in which you make a number of points about the Silvertown tunnel project. In order to understand your view, could we ask you to clarify three points.
- You refer to the need to reduce overall car use in London, which we all agree is necessary. The Mayor announced in January that he proposes to reduce the level of car use, measured by vehicle km/year, by 27% by 2030.
The consultants’ report commissioned by the Mayor from Element Energy suggested that, in its “no constraints” scenario – which is closer to the Tyndall Centre’s science-based projections for London’s reductions in greenhouse gas emissions than the “accelerated green” scenario the Mayor has chosen – a reduction of 40% by 2030 is needed. Both of these projections imply a huge uptake of electric vehicles (for the Mayor’s chosen “accelerated green” scenario, it is assumed that by 2030 46% of vehicles on London’s roads will be electric and a further 10% hybrid).
In other words, to achieve the Mayor’s climate targets by 2030, even cutting traffic volume by 27% is unlikely to be sufficient. But let us start with that number anyway.
If there is 27% less traffic on London’s roads by 2030, what is the expected effect on the Blackwall tunnel? Will there be 27% less traffic using it, or some other number? And if there is less traffic using it, to what extent will that address congestion? And why can other well-known tools of the traffic planners’ trade not be used to address the remaining congestion, if this 27% reduction is insufficient?
Has the Labour group discussed the implications of this 27% reduction in traffic, the greatest challenge for transport policy for many decades? If TfL’s financial, human and management resources are diverted to a road tunnel to carry part of the remaining 73% of today’s traffic volumes, instead of on public transport and alternative modes, is this not a poor use of those resources?
Indeed, has the Labour group discussed more widely the transport policy implications, or the implications for the Silvertown tunnel project, of the Mayor’s 2018 and 2022 policy announcements on climate change? (You say the tunnel proposals were examined prior to the DCO being issued, and by Ernst & Young in 2021, but as you know, neither of these exercises took the Mayor’s climate policies in to account. The only detailed analysis of this project in the light of the Mayor’s transport and climate strategies was done by the Stop the Silvertown Tunnel Coalition, with the Transport Action Network and others i.e. the Stop Digging report. This concluded that the tunnel project undermines those strategies.)
- Thank you for your welcome assurance that no-one from the Mayor’s office has tried to influence your scrutiny of the Silvertown tunnel project. Could you tell us, then, whether you and your Labour group colleagues would be able now to address the issues raised by Victoria Rance’s letter of 9 February 2021, addressed to Len Duvall as chairman of the Oversight Committee and copied to all members of the Oversight Committee and the London Assembly. (We attach a copy for your convenience.) The letter drew attention to shortcomings in the original modelling for the tunnel project, and material changes since that modelling was done, which we believe needed to be addressed the Oversight Committee. The letter was not acknowledged or answered by Len Duvall or any other member of the Labour group; as far as we know these issues were neither addressed by the committee, nor picked up by the Labour group, before or after the Assembly elections last year. We would welcome a belated answer now.
- We are disappointed that you do not want to meet us. We are an unelected and, inevitably, to some extent self-selected, group, albeit one which reflects the overwhelming majority of public opinion on this issue. Could we suggest, as an alternative, that we arrange a meeting between you and your colleagues, and either (a) some of the 71 climate, transport and urban policy researchers who sent a letter (unanswered) to the Mayor and the Secretary of State for Transport in April last year, warning that the tunnel project was incompatible with UK climate targets, or (b) some of the elected representatives (MPs, councillors, etc) in Greenwich and Newham who are opposed to the tunnel, or (c) a combination of these.
In addition to these three points, we hope that you will address the issues raised by Dominic Leggett of the Stop the Silvertown Tunnel Coalition in his email to you of 15 August.
Looking forward to your response,
On behalf of the Stop the Silvertown Tunnel coalition
Stop the Silvertown
c/o Victoria Rance
9 February 2021
To: Len Duvall, Chairman, Oversight Committee, GLA Cc: members of the Oversight Committee and of the London Assembly
Dear Len Duvall,
I write on behalf of the Stop the Silvertown Tunnel coalition to draw your attention to the extraordinary situation with the modelling of traffic projections for the Silvertown tunnel project.
You are well aware, from our previous correspondence, of the reasons why our coalition believes the project should be cancelled. However we are also concerned that neither the Mayor nor the London Assembly have paid attention to the flawed nature of the modelling done by TfL for the project.
The benefit-cost ratio assumed for the Silvertown tunnel is based on this flawed modelling. So is the congestion and resilience case that has been made for the project. If the modelling was corrected to take into account the induced traffic effect, as argued below, the benefit-cost ratio would have to be drastically revised.
In short, the decision to go ahead with the tunnel project, the benefit-cost ratio assumed, and the congestion and resilience case on which the decision was based, all rest on the flawed modelling. This makes a pause and rethink urgent.
The New Civil Engineer newspaper reported on 18 December that new traffic analysis for the tunnel would be carried out “to assess the impact of extending the Congestion Charge’s operating hours”. The report quoted Andrew Lunt, senior lead sponsor at TfL, as saying that “any future changes to the Congestion Charge (either in hours or boundaries) would need to be analysed as the scheme moves forward”.
While it is in some ways welcome that the impact of the Congestion Charge extension is being modelled, we are alarmed that the opportunity is not being taken (i) to correct the serious shortcomings in the original modelling, and (ii) to take account of material changes in circumstances that have taken place since the original modelling was done, that may have much greater effects on the scheme than the Congestion Charge extension. The problems as we understand them are:
(1) Shortcomings in the original modelling
(a) The assumptions used in the original modelling carried out by TfL perversely minimised the induced traffic effect. In contrast to the understanding of induced traffic built up by transport researchers over decades, the modelling exercise was conducted using an a priori assumption that the existence of an additional tunnel would not influence the number of trips across the Thames; and that only existing trips would be redistributed.
(b) In the original modelling exercise, it was assumed a priori that the combination of the user charge and improved cross-river bus connections would produce reductions in traffic that would counter any increases caused by extra road space. These assumptions contradicted the body of research over decades on the effect of providing additional road space. The GLA’s repeated reference to this modelling also obscures the reality that the effect of the user charge will depend almost entirely on political will. If the Silvertown tunnel were built, traffic would only be kept down to the 100,000 vehicle journeys a day if whoever is then Mayor keeps the toll at a level sufficient to discourage use. A populist mayor could cancel or lower tolls – and recent events such as the LTN “wars” and disputes over cycle lanes remind us that populism can play an important part here.
(c) The original modelling of the likely level of air pollution associated with the tunnel project took no account of the levels of PM2.5 emissions.
We have drawn attention to this in previous correspondence.
(2) Material changes since the original modelling was done
(a) In December 2018, the Greater London Authority issued a 1.5 degree compatible plan, and in May 2019 declared a “climate emergency”. Research has been conducted by the Tyndall Centre for Climate Change Research at the University of Manchester, showing the volumes of greenhouse gas emissions reductions needed, to conform with these policy statements. Since the Silvertown tunnel project, like all major transport infrastructure projects, will have a substantial impact on London’s emissions, the expected traffic levels (and related greenhouse gas emissions) need to be modelled, taking account of the emissions reductions required.
(b) In 2020 the life and economy of London has been impacted by the coronavirus pandemic. This has changed the way that many Londoners live and work; some of these effects are now expected to last far into the future, long after the end of the pandemic; in recognition of this, transport researchers are of the view that long-term traffic projections need to be revised. Clearly, the modelling assumptions for the tunnel project need to be revised to take these effects – which are potentially far greater than the effect of the Congestion Charge extension – into account.
(c) Another change in long-term conditions, also probably related in part to the pandemic, is that London’s population is expected to decline. When the Silvertown tunnel project was planned, it was assumed that, on the contrary, the population would continue to grow. This too needs to be taken into account by modelling.
(d) Brexit is causing deep going changes to the haulage industry: the likelihood is, that these will contribute to a reduction of the level of lorry traffic. These were not considered in the original modelling.
The Silvertown Tunnel project is the largest infrastructure investment associated with London’s transport strategy. The Oversight Committee is responsible for oversight of this project. In our view it would be grossly negligent not to call now – before construction work on the tunnel begins – for a review of the unsatisfactory modelling exercise conducted by TfL, which has led to the justification of an unjustifiable strategy.
Representatives of our coalition would be happy to meet with you to discuss this issue, as a matter of urgency. Yours sincerely,
on behalf of Stop the Silvertown Tunnel Coalition