Firefighters had to mop up the mess after a sprinkler system went off at the mental health unit at Taranaki Base Hospital this morning.
The New Plymouth brigade received the called just after 8.30am, senior station officer Nick Burke said.
''The whole secure unit was under about an inch of water covering the floor,'' he said.
Firefighters used squeegees and then wet vacuum cleaners to clear up the mess.
Mr Burke said the brigade was at the scene for about an hour.
- Taranaki Daily News
Does more need to be done to protect NZ passports?