Saturday 5 April 2014

A Network Rail Success Story: What Next for Dawlish?

The winter of 2013/14 will be remembered for quite some time as the stormiest in recent British history. On the night of February 4th, 2014, one of those storms thrashed the sea wall at Dawlish, in Devon, and the very foundations of the railway line were washed away, leaving 80 metres of track next to Riviera Terrace suspended in mid-air over nothing but the encroaching sea.

The railway line in question is the Great Western Main Line between London Paddington and Penzance. More importantly, however, it is the only rail connection between Plymouth and Cornwall and the rest of the country: while most long-distance routes have alternatives, once you get beyond Exeter there is but one route you can take to get a train to Cornwall.

On Friday, April 4th, two months after the tracks were washed away, the line reopened. Just eight weeks to rebuild a 100-metre section of sea wall from the very foundations, with workers only being able to work when it's not high tide, is nothing short of incredible and Network Rail deserve every award going for the amazing work they have done.

When Network Rail said in the days after the storm that it would be "at least 4-6 weeks" before the line reopened, many people looked at the pictures and thought it would be a lot more than that; the sheer scale of the damage was more or less unprecedented, and was clearly the biggest challenge the Network Rail team in the south west of England have ever faced. But they nearly managed to do it within six weeks; had it not been for a second storm on February 14th, which washed away another 20 metres of sea wall, they might very well have succeeded.

With the line reopened, the short-term panic over trains not running can at last subside. The focus should now turn to the long-term future of the rail network in Devon and Cornwall. On February 26th, Network Rail produced a list of options that they were considering:

  • reopening the London and South Western Railway (LSWR) route between Exeter and Plymouth via Okehampton and Tavistock (see this map);

  • create a new line between Exeter and Newton Abbot connecting two existing freight lines;

  • build one or more cut-off tunnels between Exeter and Newton Abbot to bypass the worst section of the sea wall.

However, there is a danger that, now the line has reopened, the impetus to look urgently at such plans will ebb away, and within six months most people will have forgotten that there was ever a problem with the railway line at Dawlish.

Frankly, maintaining the railway line along the sea wall at Dawlish has always been a matter of fighting a losing battle with the sea; Network Rail, just like King Canute, cannot stop the tide rolling in. It is, mile for mile, the most expensive bit of railway in the country to maintain, not least because of the salt spray rusting away at the rails. It is almost surprising that it's taken this long to have this serious a breach in the sea wall. Nonetheless, sea levels are rising, and coastal erosion is inevitable; eventually the sea wall - and the railway line that sits atop it - will all fall into the sea.

So what should be done? The trouble is that if those three options are the answers, it's not clear what the question is.

If the question is whether there should be a diversionary route that can be used as a contingency and otherwise simply provides a reasonable local service, then reinstating the LSWR route between Exeter and Plymouth via Okehampton and Tavistock looks, on paper, to be the "easiest" option: apart from a few buildings, the trackbed is reasonably intact and it wouldn't require any significant engineering works to reopen the line.

However, there are some downsides to this. Firstly, what parts of the line via Okehampton that are still open are all single-track; so while it would provide a reasonable contingency, it would be severely limited in capacity. (For more on this, see my blogpost and map from when I went to Okehmapton last summer.) Even getting a train every hour between Exeter and Plymouth on such a route would take some effort.

Secondly, the line is anything but a "main line". The existing GWR route via Newton Abbot is built as a mainline; admittedly it has a few steep gradients, but they're short and sharp, and much of the route is reasonably flat and straight. The old LSWR route isn't as steep, with a maximum gradient of 1 in 75 compared to 1 in 38; the difference is that it's a 25-mile climb at 1 in 75, followed by a 25-mile descent on the other side. So if we were to have to divert trains, they certainly wouldn't be as fast.

Most importantly, however, it's difficult to justify spending £100 million or £250 million (or however much the reinstatement of the LSWR route might cost) just for the few times a year when you might want to divert trains away from Dawlish. There has long been an argument for local services on the line, but that would probably need to be the main driver if the line were to be rebuilt; network resilience is great, but is it really worth paying £250 million rather than putting up with buses on the few occasions when Dawlish is shut?

However, if the question is about providing a replacement for Dawlish, then the LSWR route cannot be considered to be the (whole) solution. There is one simple reason for this: Torbay. The LSWR route provides a very good alternative route between Exeter and Plymouth and onwards to Cornwall; but it does nothing to provide an alternative route between Exeter and Newton Abbot, and I can't imagine that holidaymakers heading for the English Riviera would be willing to make a 50-mile detour via Plymouth.

So instead, one must consider a new connection between Exeter and Newton Abbot, more inland and resilient to storms than the Dawlish sea wall. Indeed, in 1933, the Great Western Railway proposed just such an avoiding line, but while survey and construction work began in Spring 1939, the outbreak of war halted the work and the land was sold off by British Rail after nationalisation.

While the second option above suggests using two freight branches which remain at either end, that would probably end up reducing the speed of the trains. With the Dawlish sea wall already the slowest part of the mainline between London and Plymouth (with trains limited to 60mph) it seems sensible to try and build a slightly faster railway as a cut-off. Such an avoiding line, however, would be a much bigger undertaking, especially given the amount of tunnelling that would probably be required. It would be a brand-new railway, and that comes with a much bigger price tag attached.

There is another spanner in the works: electrification. Much of the country's rail network is being electrified, with electric wires going up and electric trains replacing diesels. But in the Westcountry, the wires will stop at Bristol, at least for the time being, with services to Plymouth and Penzance being operated by diesel trains for at least a decade to come.

It's not clear whether Dawlish would ever be safe for 25kV electric wires, given the amount of sea spray that frequently comes over the trains (see this video at 2:15 and 7:00, among many others on YouTube). It may be that if Plymouth is ever to see electric trains, an inland diversionary route between Exeter and Newton Abbot will become a necessity. Then again, the railway line at Saltcoats, up in Scotland, is also exposed to the coast, and it is electrified (see this video for a storm at Saltcoats).

More importantly, however, the South West has done comparatively poorly out of recent railway investment plans; while lines across much of England, Wales and Scotland are being electrified and HS2 will bring far more capacity for long-distance services to the north, barely any investment is heading to Devon and Cornwall. I'd argue that reopening the line via Okehampton and building a faster avoiding route between Exeter and Newton Abbot are both necessary to bring the rail network of Devon and Cornwall up to a 21st-century standard.

I would like to see a wide-ranging discussion of the long-term future not just of the line through Dawlish, but the whole railway network in Devon and Cornwall; for too long the South West has suffered from having old trains and a lack of railway lines. Too often it seems like we don't do long-term infrastructure planning in this country; just this once I'd love to be proved wrong.

For now, though, I'd encourage everyone to do one thing: take a train along the Dawlish sea wall, preferably an HST with windows you can push down and peer out of. The experience of the sea air and the sight of cliffs on one side and sea on the other is simply magical, and unique to the line through Dawlish. And if this whole thing has taught us nothing else, it's that eventually the line will fall into the sea; so go, while you still can, and take a trip on the maddest, most precarious, most ridiculous, most glorious railway line in all of England.

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