Frustrated commuters will have to wait until 2023 for new rail carriages to cater for a significant increase in passengers.

Transport chiefs have confirmed that it will be several years before a new fleet of electric Dart carriages can be purchased.

Passenger numbers on Irish rail rose by 5.5% last year to some 48m and economic growth is putting even more pressure on services, say the National Transport Authority.

All available fleet is in use during peak periods, said NTA deputy chief executive Hugh Creegan, and Irish Rail is now looking at buying or leasing carriages.

Mr Creegan’s letter to Fianna Fáil TD Robert Troy in response to a series of parliamentary questions, obtained by the Irish Examiner, reveals the extent to which rail services are being tested.

“It is expected that the formal fleet acquisition tender process will be initiated in the next two months and that the fleet manufacturing contract will be awarded either at the end of this year or the start of next year.

“However, the process of having rail fleet built is a lengthy one and it will take between three and four years after the award of the contract before the new fleet will start to be delivered, probably during 2023. However, it is not possible to confirm exact date delivery dates until the fleet supplier is appointed.”

In line with the Government’s national development plan, Dart services will be expanded to Maynooth, Celbridge and Drogheda among places. The new bi-mode Dart fleet, which can operate with electricity, diesel or battery, will allow other carriages to be transferred onto existing packed routes.

In the meantime, a planned refurbishment of rail carriages to help ease capacity has stopped.

“The refurbishment approach no longer represented value for money,” the executive told the TD in the recent letter.

There are also difficulties buying or leasing second hand carriages.

Even if second hand fleet is available, it would take time, and incur considerable costs, to convert that fleet to suit the Irish network.

Speaking about the NTA letter, Mr Troy said: “It looks like commuters will have to deal with chronic overcrowding on trains well into the future as no spare fleet are available and refurbishment plans have been shelved by the NTA.

“Concerned by other issues which are not in his portfolio, Transport Minister Shane Ross has dropped the ball on transport and now we have gridlocked rail service which cannot cope. Ask any passenger on the Kildare or Drogheda line and they will tell you that they’re like livestock crammed into carriages, standing for journeys well in excess of 40 minutes.”

Minister Ross and the Government say they want a new fleet for commuter counties, but admit it will take several years to buy the new carriages.