Police are working on plans to upgrade three police stations which presented earthquake risks, and have almost finished a fourth.
The plans to strengthen parts of Palmerston North central station, and possibly a total redevelopment of the Blenheim station, should be ready in a month or two.
Rangiora station was evacuated last year and will be strengthened.
Another station, at Great South Road in Ōtāhuhu, is most of the way through a refurbishment.
At Palmerston North, the police station was one of a dozen buildings where the city council investigated the seismic designs by engineering firm Kevin O'Connor and Associates.
Two-thirds had flaws and several have since been declared earthquake-prone.
A three-storey concrete extension to the police station in 2004 was complex and needed a detailed seismic assessment, a desktop audit by engineering company Beca to the council in early 2019, released to RNZ under the Official Information Act this week said.
That assessment "shows that in the event of a moderate earthquake, one key area of the building does not meet the required design strength", the police told RNZ in a statement.
However, it was stronger than the average office building in the first place, because it housed cells.
A strengthening design and business case development should be done soon, police said.
In Blenheim, a building above the cellblock has had to be demolished after a mid-2019 assessment found it was too weak.
"The remaining buildings and custodial facility [were] then deemed safe to occupy."
By July the police should have decided on major changes to the existing buildings or a complete new build.
At Rangiora, where the station has "poor seismic resilience", upgrades are being looked at.
Police will begin a three-year quake assessment programme of all major buildings in July.