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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

Robustification of Cornish rail connectivity, part two

with 4 comments

Part one

GW severance at Dawlish (Western Morning News)Prior to being appointed transport secretary, Patrick McLoughlin showed little interest in railways or transport, so this week’s Great Western severance at Dawlish must have come as a bit of a shock to him. Today he announced a “rigorous review” of alternatives to the coastal Great Western line, raising hopes of “dusting off a £100 million inland link to avoid storm damage”, the Western Morning News reported.

The announcement was probably designed to shore up parliamentary support for the prestige £50 billion HS2 railway intended to run between London, Birmingham, and two Northern cities.

[‘Minister commissions report into battered Dawlish line alternative’, G Demianyk, Western Morning News, February 6, 2014]

Most [South West MPs] want “dual lines” – meaning a new inland route would complement the Dawlish line, as ditching the vulnerable coastal path would leave South Devon cut off and bring the demise of one of Britain’s best-loved journeys.

There are many options that could be considered for re-routing, including reviving a 50-mile stretch from Exeter to Newton Abbot, which closed in 1958.
[…]
At Transport Questions in the House of Commons this morning, the Secretary of State Mr McLoughlin said he wanted the service restored “as quickly as possible”, but also pledged a “more rigorous review of some of the other alternatives that may be available”.

In 2006, Labour ministers ruled out the idea of re-routing, arguing Network Rail believed seafront defences in Dawlish were unlikely to fail “in the foreseeable future”.

There must be a question mark over the longer term viability of the Great Western railway on its current course via Dawlish and 25kV ac overhead electrification to Plymouth would pose immense problems. The Beleben view is that an inland link would cost a lot more than £100 million, but be relatively simple compared with, say, the re-routeing of the Nice to Genova railway in Monaco and Sanremo (which was not done for weather resilience).

Protecting the entirety of the Great Western in South Devon from ‘extreme’ weather would be prohibitively expensive. There would seem to be a case for both constructing a shadow route to maintain connectivity to South Devon resorts, and rebuilding the LSWR route to Plymouth via Okehampton. Extending Waterloo — Exeter trains into Mid Devon would certainly benefit its economy.

Plymouth (population 256,000 [2011 Census]) is one of many towns cut off from the rail network by the severance at Dawlish, but HS2 lobbyist Alex Burrows attacked Devon / Cornwall rail resilience concerns

Written by beleben

February 6, 2014 at 9:31 pm

Great Western Big Spark

with 5 comments

Compared with its counterparts in France  and Germany, Britain’s railway has a very limited degree of network electrification. Only two domestic true main lines – the West Coast Main Line and the East Coast Main Line – have electric traction. Otherwise, electrification is restricted to the Channel Tunnel Rail Link (“High Speed One”), and some commuter routes, mainly in East Anglia, Greater Glasgow, and south of the river Thames.

In France, electric trains reach every region, including branch lines to small towns, such as Les Sables d’Olonne (population about 16,000).

Electrification was pursued vigorously in West and East Germany, with the latter producing more than four times as many electric locomotives as Britain.

Modest plans for extending electrification to the parts of the Great Western system (London to Swansea, Newbury, and Oxford) were announced by the Labour government in 2009, but scaled back by the coalition government.

Labour’s Great Western electrification proposal did not include the main line to Devon and Cornwall, or anywhere north of Oxford. So their rolling stock strategy entailed buying Intercity Express Project (IEP) trains from Hitachi in Japan. These tragically misnamed “Super Express” units were to operate off the electric wires where available, but carry diesel engines and battery packs for the rest of the journey. The diesel engines would also have to run on electrified sections, providing “hotel” power, and extra traction.

As well as being complex and energy inefficient, the IEP would also offer poor value for money. Despite this, there appeared to be no analysis of other options, such as a ‘Big Spark’ electrification of the principal lines to south west England and south Wales encompassing the lines in the 2009 scheme, and also

  • the London to West Midlands Chiltern line, via High Wycombe
  • Newbury to Penzance
  • Bristol to Taunton
  • the East West line (Oxford to Bedford, and the connection with the Chiltern line at Bicester)
  • Reading to Basingstoke

Compared with IEP, this approach would allow more economy in rolling stock procurement, with the use of essentially off-the shelf electric locomotives and carriages. The carbon footprint of accelerating tons of IEP deadweight (batteries and diesel engines) tens of thousands of times over a thirty or forty year lifespan would be avoided. An added bonus would be all-electric haulage of freight for many flows, such as Southampton to Birmingham.

Great Western expanded electrification concept

Written by beleben

January 24, 2011 at 1:01 am