All lines have been blocked between Lancaster and Oxenholme due to damage to the overhead electric wires.
Passengers travelling between Lancaster and Oxenholme on the West Coast main line are being advised to check before they travel today (January 16).
Work will take place throughout the evening and overnight to repair the 25,000-volt overhead cables at Hest Bank, near Lancaster.
No trains are able to run in either direction on the West Coast main line between Preston and Carlisle and replacement buses are in use between the two to keep passengers moving.
Phil James, director for Network Rail’s North West route, said: “We’re sorry to passengers affected by the problems with the overhead power lines at Hest Bank.
"We have specialist repair teams on site working as fast as they can to fix the cables and restore power so trains can safely run again through the area.
“Disruption is expected for the rest of the day so we’re urging people to plan their journeys and check before they travel with their train operator or National Rail Enquiries.”
A spokesman for Northern said: "Due to damage to the overhead electric wires between Lancaster and Oxenholme Lake District the line is blocked.
"Disruption is expected until 7pm on January 16.
"Rail replacement transport in operation."
Trains heading toward Barrow from Manchester will run as far as Preston.
Trains heading towards Manchester from Barrow will run as far as Carnforth.
Road Transport will operate between Preston and Carnforth.
Road Transport will be provided between Oxenholme and Windermere in both directions.
Road Transport will be provided between Lancaster and Oxenholme in both directions.
Northern are warning that journeys by road will have significantly extended journey times.
Passengers are advised to listen for announcements and check information screens for updates where possible.
Remember, if you've been delayed by 15 minutes or more, hold on to your tickets and claim compensation by visiting northernrailway.co.uk/delayrepay