The Minister for Justice will tomorrow seek approval from the Cabinet to close two prisons and to take responsibility for two others out of the hands of the Prison Service.
It is understood Spike Island in Cork and the Curragh in Co Kildare would close under the proposals and that both Shelton Abbey in Co Wicklow and Loughan House in Co Cavan would be taken out of the Prison Service's control.
Reports this evening suggested that inmates and staff would be transferred to other prisons, possibly in Limerick and the midlands.
Mr McDowell is also reported to be seeking a new entry-level salary grade for prison officers. He will also employ private firms to escort prisoners in a bid to cut the massive cost to the State of prison officer overtime each year.
Figures published by the Central Statistics Office this week revealed that prison officers continue to be the highest paid public servants. Prison officers earn an average of almost €1,120 per week, compared with around €632 for an administrative civil servant.
The cost of prison officer overtime this year has already reached more than €64 million, around half of which is paid to officers on escort duty.
The Irish Prison Officers Association is likely to object to the minister's moves. Talks between the minister and the IPOA this year have not been successful in resolving outstanding issues over work practices and cutting overtime.
The IPOA accused the minister some months ago of "threatening" prison officers with privatisation of prisons. However, the minister said he was doing no such thing.
A spokesman for the minister said he could not confirm details of this evening's reports. He confirmed the minister would be "discussing" the possibility of closure of two prisons with Cabinet colleagues tomorrow and that he would announce his plans after that.