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An announcement today on the future of Mt Eden Prison is expected to confirm a multi-storey mega-prison will be built on the site within three years.
Corrections Minister Phil Goff is expected to confirm the plans on a visit to the prison this morning.
The Herald understands the announcement will include plans to add as many as five new tower blocks - three new eight-storey towers and two six-storey towers - alongside existing prison buildings by 2014.
It is expected the first stage will be in place by 2011.
Site plans of the new buildings, released last year, showed two new cell blocks would house 450 prisoners and replace the current prison, which will be renovated for administration and staff use.
It is not yet known what the renovation will cost. But the Department of Corrections has approval from Auckland City Council-appointed commissioners to build the new prison on the 4.8ha site.
Included is an eight-storey jail block 30m high next to the motorway, a four-storey jail block, new gatehouse, multi-level carpark building and visitor centre.
Approval has also been granted for future projects, including another six-storey jail block and expanding the present remand centre from four to seven storeys.
The existing stone-walled jail, built more than 120 years ago, will be preserved and become an administration block.
Auckland City Mayor John Banks was reported in the Herald in December as being furious about the possible "high-rise monstrosity" replacing the historic prison.
He said buildings up to 30m high adjacent to the Southern Motorway would block views to Mt Eden and be an awful gateway to the city.
He said the area around the prison had a height limit of 15m.
Mr Goff said at the time Corrections had consulted extensively, including 18 meetings with council officers over two-and-a-half years.
The prison's nearest neighbour, Auckland Grammar, had approved the project, he said.
The country's current prison occupancy is about 8200 prisoners.
It is estimated a further 1000 prison cells will be needed by 2014.
Corrections has built four new prisons in recent years - Northland Region Corrections Facility, Auckland Women's, Spring Hill and Otago - to house an extra 1600 prisoners.
The extra building and operating costs have seen the cost per prison per day increase from $156.10 in 2002-03 to $210 in the last financial year.
Other old prisons were also up for replacement, including Wellington Prison, the old wings of Waikeria, and New Plymouth Prison.
In all, more than half of the prison stock is due for refurbishment or replacement by 2014, which the department estimates will cost $1.2 billion.
