The refurbishment of Mountjoy Prison will begin early next year following the transfer of remand prisoners.
The Mountjoy Redevelopment Group is preparing proposals for the project, and its second report will be forwarded to the Minister for Justice, Mr O'Donoghue, shortly.
The redevelopment of the entire Mountjoy complex, including St Patrick's Institution and the training unit, will start when remand prisoners have transferred to Cloverhill Prison and the Midlands prison, which officially opens on November 9th.
A spokesman at the Department of Justice confirmed that the work at Mountjoy is scheduled to begin early next year and would be completed over the next four years.
The number of prisoners in Mountjoy will be reduced by up to 200 to allow the prison to be refurbished. A permanent reduction in overcrowding is also planned, and the current capacity of 700 prisoners will be cut to around 550. The Midlands prison will provide 515 places when fully operational and is part of the Government's accelerated prison-building programme, providing a total of 1,207 additional places around the State by the end of this year.
A second phase of building expansion, approved by the Government in May, will provide a further 740 places, and planning has begun for these projects. New wings in Castlerea and Cork Prisons will each provide 150 spaces, and Cork will receive an additional 50 juvenile places. There will be 110 places for juveniles in the Dublin area.
Twenty places will also be provided in a new women's unit in Limerick Prison, and a further 20 places will be available in a halfway house for inmates on their Phase 3 of the building plan includes proposals for a closed adult prison with 240 places for Dublin.
Recent figures from the Department of Justice show a total of 3,091 people serving sentences in the State's prisons in September this year, of whom 204 were on temporary release.
A total of 2,887 people were in custody in September, an increase of 4.8 per cent on the previous year.