KEY POINTS:
The Government has finally admitted the Ngawha Prison in Northland is sinking into the ground.
The $137 million prison, which went almost $100 million over the estimated construction cost when first mooted, is now facing fix-it bills as it continues to subside into what locals claim is an old lake bed.
In 2004, when the prison was being built, the Department of Corrections insisted the jail was not sinking - contrary to what site workers were saying.
The Corrections Minister at the time, Paul Swain, said none of the structures built on the prison site had suffered from sinking, subsidence, shifting or cracking. "There are no expected future problems with site stability."
But department prison services manager William Whewell has now admitted the prison was subsiding then and still is.
He said the department investigated the cause of cracks that appeared in one building in 2005, finding they were due to uneven settlement.
They were repaired at "no significant cost".
Mr Whewell said no more cracks had appeared but the prison continued to settle slowly.
The settling was expected and planned remedial work would reinstate the building to its original alignment before there was significant damage.
The department was assessing remedial options but a start date had not been set. It would not say how much repairs were likely to cost.
"There is no impact on the safety and security of the site and the settlement is not of a magnitude that has any effect on the use of the building," Mr Whewell said.
The jail, which can hold up to 350 inmates, sits 500m above the Ngawha geothermal reservoir.
There is no direct connection between the prison and Ngawha Springs or other geothermal activity around Ngawha village, a kilometre away.
Shayron Beadle, of Ginns Ngawha Hot Springs, said the sinking came as no surprise.
She and her family had lived in the area for more than 50 years and had opposed the site for the prison.
"It was built on an old lake bed. The Government moved mountains to build the prison. They poured millions into a site that was unsuitable," she said.
"Ngawha is unusual. Springs pop up in completely unexpected places.
"It's an insane place to have built a prison."
- Northern Advocate