Map 1: Existing and Former Railways between Exeter and Dartmoor
Reproduced with kind permission of teignrail.co.uk
After a severe storm, on 6 January 1930 the Western Morning News carried the headline ‘Track Hanging Over Chasm, 40-ft Breach in Sea Wall at Dawlish, Traffic Diverted to Teign Valley’. Notwithstanding the economic rigours of the Great Depression, in 1933 it was proposed to build a Dawlish Avoiding Line. Near Exminster, the mainline would be moved inland, circumventing the Dawlish and Teignmouth sections along the coast. It would involve three tunnels under the Haldon Hills – one of which would be 2.4km in length – and rejoin the existing main line near Bishopsteignton. Some modified proposals followed. Construction started in Spring 1939, but all work stopped at the outbreak of the Second World War. It was never restarted.
Calls for the revival of the Dawlish Avoiding Line were revived after storms closed the Dawlish sea wall route in 2012 and 2013. Severe storms in February 2014 demolished a 150-metre section of the mainline. The railway was closed for two months for major repairs. One estimate put the economic cost of the closure, including to tourism and fishing in Devon and Cornwall, at up to £1.2 billion.
Subsequent work on rebuilding the line, strengthening the protective sea wall, and providing rockfall protection in the Dawlish area cost over £165 million from 2014-2023. But despite costly investments in the sea defences, storms have still interrupted rail services along the line. Take the winter of 2023-24 alone. In October-November 2023, Storm Ciarán dislodged 20 large slabs on the Dawlish sea wall, adjacent to the railway line. In early February 2024, huge waves crashed over the top of the sea wall, requiring about 50 people to be evacuated from their homes on the other side of the coastal railway. Train services were again interrupted.
Further expenditures are planned to try to alleviate the Dawlish problem. As things stand, rail connections to South Devon, Plymouth, and the whole of Cornwall, involving over a million permanent residents and additional millions of annual visitors, are vulnerable to storms affecting the sea wall stretch of railway around Dawlish. According to a recent study, with global warming and rising sea levels, storm threats to the Dawlish line are likely to get worse.
If the Dawlish Avoiding Line were not built, then two further options for avoiding the Dawlish section might be considered. One would be to extend the recently revived railway from Exeter to Okehampton further southwards through Tavistock to Plymouth. This would follow the route of the former London and South-Western Railway. This option is currently under consideration.
The re-opened Exeter-Okehampton-Tavistock-Plymouth route would involve a detour of 88 km off the mainline from Exeter to Plymouth. The spectacular Meldon Viaduct would require rebuilding. This route involves a long diversion from the existing mainline.
Re-opened in 2021, the line from Exeter to Meldon (near Okehampton) involved 39 km of re-laid track. From Bere Alston, there is an existing 12 km railway, southwards to the main line near Plymouth. The extension from Meldon through Tavistock to Bere Alston would involve 37 km of new track.
Another option is to re-open the Teign Valley Line. The UK government considered reopening the railway after the severance of the mainline track by coastal storms at Dawlish in February 2014. The Campaign for Better Transport released a report in January 2019 which described the line as their ‘Priority 2’ for reopening. The journey would be a kilometre longer than the existing mainline route, but national rail communications to South Devon, Plymouth and Cornwall would all be maintained in the event of a closure around Dawlish.
The re-opened Teign Valley rail route would involve a single-track detour of 30 km off the mainline from Exeter to Newton Abbot. It would involve only 22 km of new track, compared with 37 km on the Okehampton-Tavistock-Plymouth route.
There are strong cases for re-opening both the Okehampton-Tavistock-Plymouth line and the Teign Valley Line. The former has strong tourist potential, as it skirts the north and west of the Dartmoor National Park. It also would restore Tavistock’s links to the railway system.
The Teign Valley Line skirts the eastern flank of Dartmoor. It too has tourist potential and would serve the communities along the Teign Valley. It may be the best single option to address the Dawlish problem. Consider the marginal costs and benefits of each option, in relation to the Dawlish issue. In the event of a Dawlish interruption, the marginal benefits of the Teign Valley option, over the line through Tavistock, would be:
(a) to maintain railway links with a populous area of South Devon, including Newton Abbot and the large Torbay conurbation, and
(b) to extend the journey distance from Exeter to Plymouth by only about one kilometre, possibly adding only a few minutes to the journey, compared with the much longer deviation via Okehampton and Tavistock.
Concerning costs, both projects require substantial investment. The Okehampton-Tavistock-Plymouth requires more newly laid track and the replacement of the Meldon Viaduct. The Teign Valley option requires substantial investment, especially for the short section between Alphington and Ide, close to Exeter. As Colin Burges put it in his case for re-opening the Teign Valley Line: The costliest works would be ‘at Alphington, relining Perridge Tunnel and building a new alignment alongside the A38 between Chudleigh and Chudleigh Knighton, for which the path is clear.’
Because of its curves and gradients, the reopened Teign Valley Line would not allow for high speeds. But if they had to divert to the line because of a main line closure at Dawlish, then its relatively short distance would not delay mainline trains greatly. In addition, the line would provide enhanced transport links in a rural area and help to relieve congestion in the urban area around Alphington near Exeter.
A 2014 study by Network Rail costed the following different options as follows :
1. Reconstructing the former London and South-Western Railway route from Exeter to Plymouth via Okehampton. Estimated cost £875 million. In 2014 the Exeter-Okehampton stretch was intact and run by a private company.
2. Constructing a modern doubletrack railway on the alignment of the former Teign Valley Line from Exeter to Newton Abbot. The estimated cost was £470 million. The practical viability of a double track railway was questioned. A double track railway is not proposed here, so the cost would be considerably less.
3. A new Dawlish Avoidance line. Five alternative direct routes on a new line between Exeter and Newton Abbot had an estimated cost between £1.49 billion and £3.10 billion.
Of course, these estimates need to be adjusted in the light of inflation and additional information. The first and second options are much cheaper than the third. The first and second options should be seen as complements rather than rivals. In which case, both lines could offer relief in the event of a main line closure around Dawlish.