By Simon Montague BBC News Transport Correspondent

Network Rail faces a 'monumental' task, says Mr Bowker

Richard Bowker, the government's man who oversees the industry, says the next few months are critical. In January, he'll tell the Treasury how much extra money rail requires, to reverse decades of decline.

The chairman of the Strategic Rail Authority controls a current subsidy of �33bn over 10 years. It's thought the SRA could bid for between �10bn and �15bn extra. But Mr Bowker will need solid evidence of falling costs and improving performance, to have even a remote chance of success.

The evidence must come from Network Rail, which took over from Railtrack a year ago. The company faces a "monumental" task, Bowker acknowledges, and so far results are "unacceptable".

It's important that people understand the value that they're getting, for the money that's being invested Richard Bowker

Network Rail inherited an uphill battle that began with the Hatfield crash three years ago. Maintenance costs have soared. With increased congestion and more safety restrictions, train delays have lengthened.

Even so, glimmers of hope are now emerging. Network Rail's taking some track maintenance in-house, to compare costs with private contractors.

Case for rail

Next week sees the launch of a major leaf fall campaign, designed to deliver much improved autumn reliability.

"Costs and performance are vital components of [the bid] we present to government next year" says Mr Bowker. "We can't make the case for rail unless we have delivered on those two."

Man with a mission: Richard Bowker has a busy few months ahead

The SRA's need will be increased on Friday by a draft ruling on how much Network Rail can charge train operators for using the tracks. Tom Winsor, the rail regulator, is expected to set a total of almost �5bn a year, �1.5bn more than the SRA has in its budget for subsidising train companies.

The Treasury's already warned that next summer's spending review will be tight. If there's no more government money, then services may have to be cut.

The SRA's already ordered reductions in maintenance on lightly used lines. Big increases in fares, the other main source of rail income, are politically unacceptable.

As part of his case, Mr Bowker's determined that both taxpayers and passengers should understand why rail matters.

ASK TRANSPORT MINISTER How can Britain's transport be improved? Put your questions to Transport Minister Kim Howells 17 October at 1530BST / 1430GMT Send a question

Market share

The SRA's recent report "Everyone's Railway", argues that a more reliable network will ease road congestion, support economic growth and urban regeneration, and improve air quality.

The benefits, he says, are far greater than rail's 6% market share of all travel.

"It's important that people understand the value that they're getting, for the money that's being invested" says Mr Bowker. "The railway still touches peoples' lives even if you never use a train. The economy is dependent on a vibrant, reliable network."

Rail is really good at some journeys, but not others Richard Bowker Dave Hay's car swap experiment

But rail will always have its limits. For the likes of commuter Dave Hay, who recently took up a BBC News Online challenge to ditch his car for a week and go by train instead, the service will probably never be good enough.

"Rail won't be the answer to every journey-it doesn't always provide an alternative," says Mr Bowker. "It's not a panacea to everything. In London for example, I couldn't ever conceive of using a car, because 85% of trains arrive at stations within 5 minutes of their scheduled time."

Mr Bowker says the railways must also plan for the long term. Next week he's expected to launch public consultation on Britain's first high speed line, between London and Scotland. He declines to discuss possible routes, because he wants to make the argument for the line first, and debate later where it might run.

"Our view is that around 2015 we need to think about a step change in capacity" he says. "We can upgrade what we've got, but we know it's disruptive and difficult to do. Or we can look at a greenfield project which could deliver in a minimally disruptive way. There are some very compelling arguments in favour of a high speed line."

Growth warning

Raising the money will be a massive challenge. Promises of comprehensive upgrades to existing mainlines, made three years ago in the government's 10 year transport plan, have already melted away.

Modernisations of the East Coast and Great Western routes will now be more modest, piecemeal affairs. But Bowker warns that any failure to build more capacity will undermine economic growth, access to big cities and airports, and efforts to get freight off the roads.

MPs said people using public transport faced a 'daily trauma'

It's an argument which resonates with MPs. Overcrowding on public transport means "employers are faced with staff who are tired, stressed, and uncomfortable on arrival at work" said a report on Wednesday from the Commons Transport Committee.

In London, one solution is the east-west Crossrail scheme. Mr Bowker believes the business case is robust, and claims to be unworried by a current government review of its huge �10bn cost. Other sources say it is inevitable that the scheme will be cut back.

For the moment, the priority is more cash to reverse the decline of the past, before investing in extra capacity for the future. Mr Bowker is desperately urging the industry to provide evidence that it can deliver value for taxpayers' money.

Meanwhile, one of Mr Bowker's own strategies for better value is nearing fruition. By the end of this year, he hopes to award the new Greater Anglia franchise, combining all three existing train services at London Liverpool Street. The aim is to improve performance and quality of service, reduce costs, and simplify management.

In preparing his case for more funds, Mr Bowker says it's "time to reaffirm commitment to the railway, not to lose faith".

But at what price? That, only the government can decide.