Northern, whose rail services have been plagued by delays and cancellations, has warned passengers in the north of England they are not likely to see an improvement until May.

The train operator, which will put its fares up by 3.2% in the new year, made the admission after the latest performance statistics showed that just 40% of its services were on time, with many passengers unable to board trains that arrived with too few carriages.

Figures for the month to 10 November showed 3,306 Northern trains were “short-formed” (5.4%) and 2,406 were cancelled (3.8%). Services in north Manchester were worst affected, with 14.4% of trains short-formed. On some services, only one carriage arrived during rush hour, leaving many passengers waiting on the platform.

During one week in November, the village of Croston – near Preston in Lancashire – lost its entire rail service, with none of the 34 daily trains running at all. Locals say they have lost jobs or been forced to buy cars to keep their employment.

By the end of the year, there will have been few or no services on most Northern lines for 19 consecutive Saturdays because of strike action by the rail union RMT. Talks to resolve the issue collapsed last week with no resolution in the long-running dispute over guards on trains.

Raj Chandarana, stakeholder manager at Northern, told a meeting at Transport for Greater Manchester on Friday that it had expected to run many more electric trains by now, but a two-year overrun of electrification works by Network Rail had led to a “horrendous” shortage of diesel trains, the Manchester Evening News reported.

A spokesman for Northern explained there is a shortage because Northern Rail has added around 1,500 extra train services per week since it took over the franchise in 2016 and more services requires more actual trains. Work to electrify key lines was supposed to be finished two years ago and the operator had planned to run newer electric trains on those lines. It has not been able to, meaning some of the diesels remain tied up on lines that should be electric by now.

Chandaranatold the meeting: “We are doing what we can, but in reality, until the infrastructure improvements happen, we are not able to use the trains that are fit for purpose on electrified tracks and it won’t be until May next year at the earliest that we’ll be in a position to say at peak there won’t be short-formed trains.”

Promising only “incremental” change in 2019, he added: “Up until May we still don’t feel we have a full set of trains we can deploy appropriately to ensure the bigger trains get more carriages during peak hours.”

A spokesman for Northern told the Guardian: “Electrification on the key Preston to Manchester line was supposed to be finished two years ago but it is still ongoing. If Network Rail had stuck to their timetable, we would be running many more nice shiny electric trains by now.

“From May 2019, we expect customers to see additional services and further improvements to reliability.”

Northern also blamed autumn for some of the delays, stating on its website: “Low adhesion caused by leaf fall impacts on our ability to brake and accelerate trains at the same rate as during the rest of the year.”

Andy Burnham, the mayor of Greater Manchester, estimates the “appalling” rail service in the north of England has added 5% more cars to the region’s congested roads.

Burnham said: “The ongoing chaos on our railways is having a knock-on effect on the rest of the transport system. People have given up on the trains and gone back to their cars, adding as much as 5% extra traffic on the road. This extra road congestion is also now affecting Metrolink [tram] services.”

In 2016, 70% of commuters in Greater Manchester (940,100) travelled to work by car. If Burnham’s estimate is right, that means a further 47,000 people are driving or being driven to work because of the disruption to train services.

A study earlier this year found Mancunians were already being exposed to dangerous levels of air pollution. Central Manchester has the highest rate of emergency hospital admissions for asthma in England, more than double the national average.

At St Ambrose RCprimary school on Princess Parkway, one of the main routes into the city, pollution levels are so bad that teachers can no longer open windows in the classroom.

A new east-west railway line across the Pennines, known as Northern Powerhouse Rail, is being developed as a solution to the region’s transport woes. But the strategic business case for the line has been delayed amid fears the government is trying to cut costs on the multibillion-pound project.

Last Monday, Transport for the North (TfN), the statutory body set up to advise the government on northern transport needs, told the Guardian it expected to submit its “strategic outline business case” for Northern Powerhouse rail to Chris Grayling, the transport secretary, before the end of the year.

But on Thursday, the TfN board refused to sign off on the plan, believing it was still too vague, the Guardian understands.

On Friday, Barry White, the chief executive of TfN, wrote to stakeholders to say the business case would not be submitted to Grayling until February.

“This will allow for further consultation with our members and greater chance to digest the detail of the document,” he said.

On Sunday, it was reported that the government had “betrayed” Liverpool in the autumn budget by withdrawing £7bn the city thought it was getting for a link to HS2, the high-speed line from London to the north.

That line would be used to link up to Northern Powerhouse Rail, creating 20,000 extra jobs and £15bn in economic development, Liverpool authorities had argued.

The government said it would not take any decisions on that link until it received the business case for Northern Powerhouse Rail from TfN. Meanwhile, it has loaned Transport for London £350m as delays to the £15bn Crossrail project leave it facing a serious funding shortfall.

Burnham said: “It is time for a clear statement from ministers that sorting out transport in the north is their single highest priority. We can’t carry on like this.

“We need a clear action plan, agreed with the government, for putting things right in the short and long term. Cost overruns in the south can’t be allowed to jeopardise the investment the north desperately needs.”

Steve Rotheram, Metro mayor of the Liverpool city region, said: “It’s a scandal that after months of misery for rail passengers across the north that Northern should now say passengers won’t see any improvements until May 2019.



“To add insult to injury, rail travellers and businesses across the north will continue to suffer whilst receiving an additional slap in the face in the shape of a 3.2% increase in rail fares.”

Asked what the government thought of Northern raising fares while also warning of a poor service for the first four months of 2019, a Department for Transport spokesman said: “We are monitoring the reliability of train services in the north closely. Richard George has been appointed to review the region’s rail performance and to make recommendations on how to deliver improvements.

“The key issue behind the disruption passengers have experienced in the north since May has been Network Rail’s failure to deliver infrastructure improvements on time.

“Network Rail will now spend an additional £15m on an enhancements package for Northern and TransPennine Express customers.”

• This article was amended on 10 December 2018 to clarify Northern’s position regarding diesel trains.