Widths & clearances

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4.11.12

 

Fact 1 - The mini conversion lobby claim that the formation of the entire rail network is wide enough for a minimum of two road lanes, often as dual carriageways, and much could be converted to three or four lane roads.  It claims that bridge & tunnel width/height would permit double deck buses and HGVs at 60 mph, without scraping walls or roof. It bases this claim on the erroneous belief that the early advocates of conversion, ex-army officers Lloyd, Watt and Dalgleish measured the whole railway. They quoted figures based on government standards introduced in 1859 after 10,002 route miles of railway had opened – mainly between cities & major towns. Those standards were not retrospective, hence below-standard routes remained. Those standards did not apply to goods traffic routes. Due to tight clearances, it was necessary to fix overhead electrical equipment to the outside of bridges or viaducts or on cutting walls, (see photos in Railway Conversion – the impractical dream). The Conversion League submitted conversion plans in 1960, Transport Minister Marples rejected it: ‘The idea is open to insuperable objections. The estimated cost is much too low and does not take account of construction of junctions. Unless all over-bridges and tunnels are rebuilt, it would be unusable by large vans or double-deck buses. It would require a very high capital investment. The possibility is not ruled out of conversion of disused lines where the necessary widening can be arranged.’ Marples was described as “A Minister of Transport, who was not only road biased, but a successful road contractor”.  (D.Henshaw - The Great Railway Conspiracy). See photos showing width & clearance problems

Fact 2 - Only one conversion study of a specific route was done. It was praised as proof positive by Transwatch - the sole remaining advocate of conversion. The total route mileage was 160. It would abandon 26 miles (16%) of that route, and divert all ex-rail traffic in new road vehicles onto an existing road. This abandoned section of line was mainly on embankment or in cutting, had 53 bridges & 5 level crossings. Abandonment avoids serious conversion problems. Towns served directly by the main line would be served by buses meandering off a busy trunk road & along minor roads. The rest of the route listed 139 bridges, half of which – the study stated - required structural changes to create clearances that would still be below DfT standards. Property purchases were required to create width at 13 locations. A significant number of bridges on OS maps were not mentioned, hence, clearances are unknown. It is unrealistic to claim as Dalgleish did in Truth about Transport that no valid objections could be made to acquisition of land which, he admits would be essential, or that motorists may desert motorways to travel on converted railways !

Fact 3 – In 1955, the Institution of Civil Engineers debated the Lloyd proposals. They were demolished by road engineers and road transport operators. It is claimed by Transwatch that this ‘debate continued until 1958 in the pages of The Engineer’. In fact, the subject actually re-surfaced in that journal in 1958. It was almost certainly revived after having been ignored by a conference of road engineers in November 1957 to resolve road congestion. Two speakers in November were at the 1955 debate and aware of the concept. No conversionists were invited, and the idea was not mentioned. The editor of The Engineer called on the Conversionists to provide details of practicability. They said it was government’s job to do that! Fifteen wrote in favour, five of whom were Conversion League members; 44 wrote against, of whom, only two were from railways.

Fact 4 – The Railway Conversion League could have commissioned consultants but failed to do so. In contrast, BR commissioned such a study. A study (The Report on the potential for the conversion of some railway routes in London into roads,) was published in March 1984, by consultants Cooper & Lybrands jointly with G. Brian Parker, a highway planning consultant, listed double track formations that would not accommodate any width of a two-way road. They would be as little as 5.9m against a DfT standard of 7.3m. Details of the Report were included in Railway Conversion – the impractical dream.

Fact 5 - Transwatch say the normal width of a 2-track tunnel is 24 ft, but quote no source. Network Rail was unable to provide data on the minimum width of tunnels without research, and were not prepared to do this. BR Yearbooks recorded over 1000 tunnels. British Railway Tunnels lists 52 over a mile long, another 56 over half a mile long. Tunnel sides are not vertical, and have refuges for staff to stand in as trains pass – emphasising limited width. A few open shafts provide ventilation - inadequate for roads. It would take years to create sufficient powered ventilation shafts. Sites would need access roads & power supplies. Conversionists have not costed power lines to new rural substations to ventilate & light tunnels. There is no ‘typical’ width for a double track line, as claimed by Transwatch when he invited me to spend a few minutes checking an unnamed ‘typical’ location. With 40 years on railways, I have spent thousands of hours on the track – on foot or footplate & can confidently say there is no such thing as a ‘typical’ width. I have walked through tunnels in different parts of the country and vouch for there being no ‘normal width of tunnels’. Single line tunnels not mentioned by Conversionists abound.

Fact 6 – ‘Conversions’ claimed to have been made, total about 250 miles, against 10,000 miles closed. That 250 miles includes sections of 100 yards or so, closed railways crossed at a tangent, existing roads widened onto an adjoining disused track-bed, one which it was ‘not clear if bypass actually built on railway’, and other irrelevancies. One conversion of a single line at Barton to a dual carriageway is shown by photos in a book (Past & Present in the North East by Robinson & Groundwater) was 12 ft wide increased to 102 ft for that motorway! Of over 200 ‘conversions’ publicised, 65% are less than one mile in length. Data from local authorities reveals widening of disused railways by a factor of up to eight.

Fact 7 – Most closed railways become footpaths/cycleways/bridlepaths for which limited width is not a problem, confirming their unsuitability as roads.

Fact 8 – Transwatch claims the British Transport Commission (which ran Railways) published widths of the whole railway system in 1961. When asked for the source, it admitted that the document quoted specified railway length, not width. Measuring varying land widths over 20,000 route miles of railway would have been costly, with no benefit. The Treasury would not have approved. Major Dalgleish – sometime conversionist spokesman – in ‘The case for transforming railways into motor roads’ specified widths – but gave no source, and admitted estimating  ‘average standard clear levelled formation width of railways’. This meant measuring width throughout the [then] 17,000 miles, and calculating an average!

Fact 9 – ‘Conversions’ reported by advocates have been checked with local authorities, (see details in Railway Conversion – the impractical dream). They state that rail width had to be increased by land purchase, by filling cuttings, opening out tunnels, lowering embankments etc. All would require compaction & drainage.

Fact 10 – Conversionists argue that the width outside the formation used by trains gives width for roads. This includes walking areas (the cess), embankments, cuttings, ditches and other uneven land. Despite this, advocates claim that the area between fences is compacted by thousands of heavy trains and needs only a few mm of asphalt more than recommended for domestic driveways to convert railways for use by HGVs and PSVs. (see cross section diagram of formation etc)

Fact 11 – Conversionists argue that the inevitable below-DfT-standard clearances for bridges on converted railways and below-DfT-standard lane widths will be adequate and safe at 60 mph. In that case, all m-way lanes should be reduced and verges concreted giving 5 lanes each way. That would solve any congestion problems for some time.

Fact 12 – In a recent letter, Transwatch included a photo of a concrete viaduct on the North Devon Link Road, said to be railway viaduct ‘proving’ that railway viaducts on single lines were wide enough for two-lane roads. The location was on the closed Taunton to Barnstaple line. The rail viaduct was of steel lattice construction, (see Taunton to Barnstaple line, by Mitchell & Smith, which mentions that a new concrete viaduct was erected at this site as part of a new road – which then had to skirt round the adjoining hill, because the tunnel was not wide enough for a road. Click Filleigh Viaduct

Fact 13 - Brigadier Lloyd told the Institution of Civil Engineers in 1955, that ‘if drivers slowed excessively at 24 foot bridges and tunnels, the question of widening should be taken up. Most of the interesting engineering problems arise at these points!’ No professional would countenance post-conversion widening. He gave no source for his tunnel width. Co-author of the East Anglian conversion study told a critical Country Life (12.2.76) writer that he envisaged (but didn’t mention it in his Study) that ‘vehicles would slow down in tunnels’. Trains don’t

Fact 14 – Dalgleish stated in The Truth about Transport that ‘the DoT specification for converted roads is needlessly elaborate, & they [railways] can be paved as they stand. However, after experience, improvement may be needed!’ By inference, m-ways are needlessly elaborate with hard shoulders, verges, huge junctions, vast service areas, lighting, signalling and information equipment. Inevitably, experience will prove a need for hard shoulders, lighting, signs, extra lanes and improved junctions. He stated, in the same document: ‘that there is no reason to insist on 5m bridge height initially, as existing roads are littered with sub standard bridges; 4.5m would be adequate initially.’  Damage by lorries bashing into bridges led to a special investigation by H&SE. His plan was that - after experience - bridges would be lifted. This unprofessional approach, with post-conversion closures widen roads or rebuild bridges would create horrendous delays.

Fact 15 - The relative requirements by the DfT for motorways and railways are depicted in a diagram - click diagram. (also in Railway Conversion – the impractical dream). The outer box represents width and bridge height for a three-lane motorway; the larger hatched box is the maximum for a four-track railway; the smaller hatched box is the maximum for a double-track railway. The space between would accommodate a further three-track railway. It will be seen that the width required for one three lane motorway is wide enough for three main lines! 

Fact 16 - Bob Menzies, Head of busway delivery, Cambridgeshire County Council  - a dedicated ‘bus’ man wrote in the Cambridge News 12.8.10: Naunton Pugh asks why the busway needed to be guided (Letters, August 4). Let me help clear this matter up again. The main reason for a guided busway is the fact a standard road would not fit down the narrow strip of closed railway that the busway has been built on. Buses on the guideway are restrained within two kerbs, meaning they can travel much closer together. National standards for a normal road means the lanes are wider and verges are needed at either side of the road.

 

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