The government is building a $300 million data centre to protect information that needs high security.
The centre in West Auckland is the only government-owned one among about a dozen big data centres being built here.
Work by 150 construction workers has been going on for three years at the Whenuapai Air Force base.
The government said it was revealing the project now in order "to be more upfront about national security challenges", as recommended by the royal commission of inquiry into the mosque attacks.
"Construction has progressed to the point it's now going to be visible and it's time to bring the public in," the Minister of Defence and Minister Responsible for the GCSB Andrew Little said in a statement.
It was for "protected government information" from a broad range of agencies, but "not vast amounts of private information about individuals".
Though a lot of public data was and would continue to be stored in privately owned data centres, there were "additional security risks with storing it in a private-vendor cloud", Little said.
Security was a bottom line at the new government centre, hence locating it within a military base with existing high physical security, Little said.
The data centre is expected to open in 2025.
