Silvertown Tunnel: our open discussion with TfL
Matt Yates, Head of Planning Projects at TfL, gave at our open meeting on 19th May a short presentation of the current status of the proposed Silvertown Tunnel and fielded a barrage of questions in a Q&A session.
Below is a summary of the Q&A with apologies to those that are truncated or even omitted. The Q&A adds to the responses to our written questions to TfL to which we are still awaiting two answers.
How do you deal with great uncertainties in forecasting traffic?
There are 3 steps: a baseline forecast on what now exists; a reference forecast which includes approved projects (eg IKEA) and sensitivity tests on possible projects (eg an outlet centre at the O2). There always needs to be professional judgment and that may be a “bit of a punt”.
How can TfL reconcile more HGV traffic with the need to improve air quality?
Air quality (AQ) is a big issue and TfL think a better traffic flow will help reduce pollution. Mitigation measures could also be added.
What can be done now to reduce the high level of traffic incidents, particularly overheight trucks?
There will be better signage to guide drivers. But now many drivers (over 600 a year) seem oblivious and need to be rescued; they do not pay a fine.
Why not use tolls now on the Blackwall?
Although tolls can manage demand, there is still need for a better facility to assist growth and offer better resilience.
AQ in East Greenwich is so bad that any more traffic would be disastrous; and major new traffic generators are planned.
The proposal is not to greatly increase traffic; rather to improve flow, improve resilience and traffic flow.
What exactly are the extra AQ mitigation measures?
Better bus services would be possible. The 108 service is severely disrupted today. The real key is to avoid the pinch-point at the tunnels and ease traffic flow on many junctions.
Is the proportion of Greenwich residents who supported a crossing (0.6%) sufficient to support the scheme?
The consultations, 3 so far, have been extensive, very detailed and open. There is 83% support for the scheme over London as a whole.
What is the difference in emissions between idling and flowing traffic?
Static traffic caused by congestion is a major problem and a major argument for new tunnels [see EGRA’s previous question number 9, which remains unanswered].
What will the toll levels be and won’t tolls divert traffic to the Rotherhithe tunnel?
Setting toll levels is a bit of an art but we think we have got them about right, by comparing them to the Dartford crossing. Models suggest that traffic will not divert to the Rotherhithe.
Why build the Silvertown tunnel before other lower river crossings which would better relieve the Dartford crossing?
The Silvertown addresses the very real problems of the inadequate Blackwall tunnel. The tunnel is the severe pinch-point on crossing the river in east London.
What are TfL’s traffic models based on?
GLA probably has some of the best and most robust traffic models in the world. They are well tried and open to public scrutiny.
Are 3800 people who supported the scheme [without tolls] out of a city of 8 million sufficient to build an £800 million plus project?
The consultation was widely advertised and accompanied by many road shows. The final consultation will take place in autumn this year.