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Network Rail claim that the current Meldon viaduct could not be restored for railway use

Network Rail claim that the current Meldon viaduct (in Option 3) could not be restored for railway use

Network Rail has provided transport secretary Patrick McLoughlin with its West of Exeter Route Resilience Study, which was established following the storm damage at Dawlish earlier this year. But who actually undertook the study, is not apparent.

[Network Rail]

Appraisal work was commissioned by Network Rail to assess the outline business case for each of the seven potential diversionary routes described in the previous section. The scope of this appraisal activity can be summarised as follows:

• To establish a base case, the existing railway via Dawlish would remain the only rail route between Plymouth and Exeter as now. This base case also includes review of the extent to which the Dawlish route could be expected not to be available for traffic due to planned engineering possessions and unplanned disruption, and the road replacement services to be assumed

• To identify the scale of disruption compensation costs for the base case, which potentially could be avoided were an alternative/diversionary route to be available

• To devise appropriate train service specifications for each route option, taking advantage of the new route:

– For planned train services only where it offers journey time savings compared with the existing route via Dawlish

– For diversions on those occasions when the route via Dawlish is not available for traffic

• To assess the likely scale of passenger demand and revenue impacts for each option

• To assess the annual operating costs for each option

• To prepare an outline UK rail financial business case appraisal and DfT WebTAG compliant transport economic appraisal, including unpriced user and non-user benefits. The appraisal compares the seven alternative/diversionary route options against the base case

• To test the extent to which stakeholders’ aspirational higher train service level scenario would change the appraisal results, together with appropriate sensitivity testing to illustrate the robustness of the results and conclusions.

In all the options, the route via Dawlish is retained with existing calls at the intermediate stations maintained. It is assumed that in the short to medium term works will have been undertaken to the route to ensure comparable standards of resilience to levels of risk similar to the average over the last 40 years.

Network Rail Great Western route to West Devon and Cornwall, west of Exeter resilience options, 2014

The study considered the following courses of action:

• Option 1, Base Case (maintenance / repair / operating regime same as pre-breach)

• Option 2, Strengthening the existing railway, is the subject of a separate Network Rail study, due to report in the first part of 2015. An early estimated cost of between £398 million and £659 million would be spread over four Control Periods with a series of trigger and hold points to reflect funding availability, spend profile and achieved level of resilience

• Option 3, Alternative Route A – rebuild the former London & South Western Railway route from Exeter to Plymouth via Okehampton and Tavistock at an estimated cost of £875 million

• Option 4, Alternative Route B – constructing a modern double track railway on the alignment of the former Teign Valley branch line from Exeter to Newton Abbot. This has an estimated cost of £470 million. There is doubt as to whether a resilient railway is practical on this route

• Option 5, Alternative Routes C (C1 – C5) – five alternative direct routes to provide a new line between Exeter and Newton Abbot at an estimated cost between £1.49 billion and £3.10 billion.

The study found that Options 3, 4, and 5 represented very poor value for money, while the VfM of Option 2 was “To be assessed”.

Although not stated explicitly in the study, in conventional transport economic terms, the best performing option would be the current, “reactive” Option 1, but the wider economic impacts question was not really addressed. The Great Western Main Line is not an “economic lifeline” for the South West, but the option of closing all lines west of Exeter was not on the table.

Currently, the vast majority of passenger travel to and from the peninsula is by road, and railfreight volume is negligible. But if South West rail access is to be maintained and developed, the best long term option would probably be to abandon the coastal alignment at Dawlish, and build something like Option C5. The Option 2 notion that the coastal route could be made storm-proof, sea-level-proof, and electrification-ready, for “£659 million”, looks highly suspect.

According to Network Rail, Option 3 is unattractive for a number of reasons. Construction of a new viaduct at Meldon would be required, and the running of stopping trains between Plymouth, Okehampton and Exeter would generate minuscule economic benefits and revenue.

Shortcomings in the study include the lack of detail about what Option 2 would actually involve, and the absence of a cost breakdown of Option 3. The storm damage in early 2014 cut off rail access to the South West for around eight weeks in the off season, but the cumulative sum of disruption from meaningful hardening of the existing route over four Control Periods (i.e. two decades) would probably be a large multiple of that. So, in the humble view of the Beleben blog, Option 2 is likely, in disruption terms, to prove a cure worse than the disease.

Network Rail west of Exeter assessed options, 2014

Network Rail west of Exeter options, 2014. Note the curious absence of a VfM assessment for Option 2

Politically and publicly, do nothing (Option 1) is ‘not an option’, but significantly improving the resilience of the existing railway (Option 2) is not achievable without effectively rebuilding it over a distance of several miles. The study glosses over that fact, which would tend to suggest an ‘Option 2 Lite’ (Option 1 dressed up as Option 2) is the preferred option.


Written by beleben

July 16, 2014 at 11:04 am

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