A new 1500 bed facility at Waikeria Prison in the Waikato has been proposed as part of Phase Two of the Government's Prison Capacity Programme.

To cater for New Zealand's growing prison population the Government will invest in a further 1800 prisoner places at three exisiting facilities at a construction cost of about $1 billion, says Corrections Minister Judith Collins.

Next month ministers will consider the new Waikeria facility's business case for formal approval. Waikeria is where most Bay of Plenty prisoners serve their sentences.

Corrections will also propose increasing the delivery of rehabilitation programmes at the prison, such as Drug Treatment Units, reintegration programmes, education and training programmes and Special Treatment Units to help address violent and sexual offending.

Judith says the new Waikeria facility will be operated by Corrections but built and maintained by a Public Private Partnership, similar to that being used by Corrections to build its new maximum security facility at Auckland Prison.

'The construction of a new facility for around 1500 prisoners at Waikeria which could be delivered in two stages - would be a significant contribution to ensuring that Corrections can accommodate the forecast numbers of prisoners.”

This week the Government approved an increase in double bunking in the Northland Region Corrections Facility at Ngawha by 80 beds, plus a new accommodation block to be built at Mt Eden Corrections Facility, adding 245 beds.

Judith says despite progress in reducing crime in New Zealand, the number of prisoners has increased faster than projected.

This is due to the numbers of offenders charged with serious crimes increasing, which means more people are being remanded in custody and serving more of their sentences in prison.

'We have to respond through new investment or we will create unacceptable safety risks for staff, prisoners and the public, and be less effective at rehabilitating prisoners.

'We're already adding 341 prisoner places through the use of double bunking and converting facilities to accommodate prisoner beds. This is part of the financial commitment we made in Budget 2016 to Phase One of the Prison Capacity Programme.

'But as we look out over the next five years this will not be enough.”

While most of the forecast demand is expected to come from the upper North Island, Waikeria is in a good location to serve this demand as it is 'close to the areas of need”, which will reduce costs of operating the prison network and help keep prisoners close to family and support networks.

Judith says Phase Two of the prison programme is not just 'about bricks and mortar” but will also be aimed at the drivers of crime, drug and alcohol abuse and domestic violence.

But NZ First Youth Affairs spokesperson Darroch Ball believes the $1b to be spent on more prison beds would not be necessary if the justice system stopped youth from going on to offend as adults.

'Half of all adult prisoners have previously been convicted as a youth. But the youth justice system is failing, so the government announced spending of $1 billion for another 1800 new beds in adult prisons.

'Instead of being the stopping point in a short life of crime the youth justice system is a breeding ground and conveyer belt for criminals.”

Darroch says the vast majority of youth offenders are 'just being re-cycled around the system”, getting warnings or diversion and continually reoffending.

'We need investment to correct and address our youth system instead of throwing billions at the problem when it's far too late.”