It has been a frustrating morning for Merseyrail passengers, with delays, cancellations and chaos across parts of the network.
Merseyrail had warned that a forecasted drop in temperatures overnight would mean the first services of the day on each line would have to run without passengers. What actually transpired was a lot more problematic.
There was major disruption on the Northern Line, with all services from Hunts Cross suspended and trains instead running only from Liverpool Central to Southport and visa versa. To add to the frustration, a message from the operator told passengers that ice on the roads meant rail replacement buses were unable to serve its stations.
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On the Wirral Line, all services between Rock Ferry and Ellesmere Port have also been suspended, with passengers told to use Chester services and change at Hooton. Those same Chester services, while running, have also been subject to delays.
So why does a drop in temperatures create such chaos across large parts of a rail network and force thousands of people into difficult circumstances? This is a major rail operator serving a world famous city region of the United Kingdom.
Well one reason why Merseyrail is more badly affected by cold weather than other transport networks has to do with how it gets its power supply. The network is powered by a "third rail" - which carries the electricity supply into the trains.
The trains pick up power from the third rail and anything in between it - like ice - can reduce the amount of electricity flowing into the train. This can cause trains to move more slowly and in some situations can stop them running at all.
The third rail is on the ground, so is far more susceptible to being frozen than the overhead power supplies or lines used by other networks around the country. Unfortunately this does mean that even when the long-awaited new fleet of Merseyrail trains start to arrive on the network, they could still be affected by similar issues during future cold snaps.
Merseyrail says its teams were out overnight treating the tracks to try and avoid this and in some areas it worked, with normal levels of service running on the Kirkby, Ormskirk, West Kirkby and New Brighton lines. The operator said that temperatures were lower in Hunts Cross and Ellesmere Port, meaning the cold and ice was too impactful and stopped trains from running.
In a statement released today, Merseyrail acting Managing Director Jane English said: "Due to freezing temperatures overnight, some lines on the Merseyrail network suffered significant disruption at the start of service today (18 January).
"We apologise to passengers who were affected by these delays, which affected the Chester and Ellesmere Port lines to Hooton, and Hunts Cross to Liverpool Central particularly.
"The Chester and Ellesmere Port line was affected by ice on the third rail, making it extremely difficult for the train to pick up power. This led to delays on this part of the network.
"The Hunts Cross line was similarly hit by icing on the powered third rail, causing similar problems in that area. We had Merseyrail and Network Rail colleagues working hard overnight and into this morning to deal with the cold issues. However, in some parts of the network the ice build-up was significant.
"We are working hard to get all services back to normal as soon as possible. Services on the Kirkby, Ormskirk and New Brighton lines were unaffected this morning. There were minor delays on the West Kirby line, while Southport services terminated at Liverpool Central."
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