The Government is scrapping National's mega-prison plan for Waikato's Waikeria prison and instead building a new unit featuring a purpose-built mental health facility.
The first sod for the construction of the new-high security unit will be turned in August, with hopes offenders will begin to be locked up by early 2022.
In making the announcement this afternoon, Corrections Minister Kelvin Davis says National's mega prison would simply be a breeding ground turning low-level criminals into more hardened offenders.
But National says it's a cop-out by the Government and puts the public in danger as there will not be enough beds to house serious criminals. The party had 1500 new beds scheduled for its prison.
They will instead have to be freed and put back on the streets.
Davis said building a mega prison was "just not the right thing to do" and "just lazy politics".
"American-style mega prisons are crime-breeding factories. They swallow up young offenders and spit out hardened criminals, sometimes a fully patched gang member. They do not keep communities safe."
Corrections CEO Ray Smith said about 50 per cent of the new beds would be double bunking.
He also confirmed that psychiatric staff will be permanently on site in the new mental health facility.
Davis said smaller prisons were more effective in "providing real rehabilitation" as they allowed prisoners to be closer to family, staff morale was higher and were safer as they "were able to better monitor prisoner wellbeing".
Davis said the Government is aware of the bulging prison network so have approved the construction of 976 more beds at five different prisons around the country to help relieve the pressure.
"Decades of rushed policy and reactive decisions have gotten us to this point today. First off we need to find a way to deal with the numbers of people currently coming through the prison gates.
"We need to add beds to the system to relieve some of the immediate capacity pressures over the next 12 months. That is why we have already approved the construction of 976 rapid builds."
When questioned as to why it's smaller prison would cost nearly the same amount as National's proposed mega prison, Davis said a lot of the cost was the infrastructure itself, including setting up of stormwater and sewerage.
Davis said new programmes, including removing administrative barriers preventing the release of those who are eligible for bail, were on track to save a further 150 beds, freeing up $15 million in costs.
He defended the Government's choice of a smaller prison, stating they wanted to focus on reducing the prison popularion to try reign in forecasted prison-number blowouts.
When told he's likely to get criticised for his choice, he replied "I have been criticised for a lot of things".
Opposition Leader Simon Bridges said the Government was going to make it harder for police and the courts to send criminals to prison and allow serious offenders to get out sooner – all because the Government is trying to save money by not building a new, much-needed prison.
"Recent conservative estimates put the forecast prison population at 12,500 by 2026 – around 2000 more than now – and that doesn't include the 900 more beds the Government has been told it will need as a result of having more police on the streets.
"That means New Zealand will be hundreds of prison beds short of what's needed.
"The Government's pledge to cut prison numbers by a third is reckless."
National's Corrections spokesman David Bennett said by not having that capacity it put New Zealand residents at risk because there were going to be a lot of serious criminals that were going to have to be let out of prison.
"So whether it's a small or a big prison isn't the defining factor ... it's whether you've got capacity in the system. And they won't have capacity now."
He said although a specific mental health unit was a good idea, it would only skim the surface on the huge number of prisoners who were affected by mental-health issues.
"A vast majority of prisoners have mental-health issues and so just picking out 100 of them that are the more severe cases doesn't actually provide the rehabilitation we need for a vast majority of prisoners."