The £1.5 billion deal will also see new fleet rolled out across the network.
Heatwave Trains: Calls For Explanation
Rail Minister Norman Baker has asked Network Rail to explain how train passengers, including those in East Anglia, were left "stranded in very uncomfortable conditions" as temperatures rose as high as 32.
National Express East Anglia reduced speeds on Monday from 90 to 60 miles an hour and cancelled some trains because of overhead wires getting too hot between London and Ipswich.
Mr. Baker is asking for an explanation, saying: "It is worrying that a significant amount of rail services were disrupted yesterday due to the hot weather, leaving passengers stranded in very uncomfortable conditions. We need the railway to be resilient, especially with the possibility of climate change causing more extremes of temperature in the future. I am asking Network Rail to explain to me what happened yesterday and what steps they are taking to try to prevent a recurrence."
But Network Rail have said a number of incidents had nothing to do with the hot weather and that it's not correct to say that the infrastructure could not cope with a heatwave.
A spokesman for Network Rail said: "There has been an assumption that everything that has gone wrong was due to the heat. But we had incidents that were nothing to do with the heat, such as broken-down trains and trespassing on the line."
They also told Heart yesterday that only a small number of trains were affected and most of those arrived on time.
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