Main lines closed as Britain swelters in record temperatures
No trains ran on the East Coast Main Line or Thameslink at the peak of the July heatwave as temperatures reached a new record.
A RED extreme heat warning for a large swathe of South East England, the Midlands, and South Pennines on July 18/19 had a severe impact on the railway network.
With temperatures reaching a new UK record of 40.3°C (104°F) at Coningsby, Lincs, a National Emergency was declared by the Government.
Based on forecasts some 48 hours in advance, the decision was made to close the East
Coast Main Line between the hours of 12.00 and 20.00 on July 19 for all services and operators between London King’s Cross and Leeds/York.
In a bid to combat the effects of the heat, Network Rail teams were out in the lead-up painting sections of many switches and crossovers white to reflect the heat and mitigate the effects.
On July 19, Thameslink suspended all of its services north of St Pancras to destinations including Bedford, Peterborough, King’s Lynn, Cambridge, and also between Stevenage, Welwyn and Moorgate. Additionally, East Midlands Railway suspended its Corby electric service, running only one diesel train per hour to Sheffield and one per hour to Nottingham.
Services out of Marylebone were running to a restricted timetable, but trains from Euston were suspended after lunchtime following a domestic lineside fire at Harrow, resulting in trees falling onto the slow lines. At Birmingham New Street, there was disruption caused by faulty overhead cables. Cancellations south of London were widespread too.
As a result of the speed restrictions, journey times on ECML services were considerably extended. The down ‘Highland Chieftain’ on July 18 was impacted by a lineside fire south of Newcastle and then overhead problems near Widdrington (Northumberland), resulting in an arrival at Inverness 236min late.
Mitigation measures were also put in place in Wales and Scotland, where timetables were adjusted as speed restrictions took their toll.
Advance planning
In the lead up to the heatwave, forecasters had been predicting temperature records could be broken. The warnings were followed by advice to passengers to delay or defer journeys before or after the heatwave.
As well as a health risk to passengers and staff, it was the infrastructure that was giving the greatest cause for concern, as track temperatures can be up to 20°C in excess of ambient temperature, exacerbating the risk of a derailment. Track laid on wooden sleepers rather than concrete is more susceptible to heat distortion.
The heat, added to the forces of passing trains, can lead to instability, increasing the risk of rail buckling, and is a key reason for lower speeds and therefore reduced forces on the track. Heat was the cause of tracks buckling at Vauxhall on the approach to Waterloo. Here the track was recorded at 48°C (118°F), but at a site in Suffolk a track temperature of 62°C (143°F) was recorded.
Excessive heat will also expand the 25kV overhead wires, leading to sagging and the associated risk the wires might get tangled around a pantograph and create more widespread damage. Although there is a counterbalance system to keep the wires tensioned, the expansion in the temperatures experienced exceeds what can be counterbalanced, and therefore the wires sag. For this reason, strict speed restrictions were imposed on many routes, special timetables were introduced, or services cancelled all together.
The overall impact on train services varied route by route, but Network Rail warned of a high likelihood of cancellations, delays and last-minute alterations.
After effects
Even after the heatwave had subsided and temperatures fell by around 10°C, Network Rail teams were busy making repairs.
Despite a huge effort, some key route sections remained closed on July 20, until the completion of repairs, including the ECML south of Peterborough after a fire at a level crossing at Sandy, and the WCML between Lancaster and Carnforth, meaning a reduced service or cancellations.
Sam MacDougall, operations director for Network Rail said: “Closing the line to traffic is always a last resort but it was the right thing to do to keep people safe given the unprecedented heatwave forecast.
“The forecast temperatures are well above those for which our infrastructure is designed, and safety must come first.”
“Closing the line to traffic is always a last resort but it was the right thing to do to keep people safe given the unprecedented heatwave forecast”