The dam that provides about half of Whangarei's water supply is now less than half full.
The Whau Valley dam level has been dropping by 1% every couple of days as drought conditions force Whangarei District Council to ease its river intake.
It is now just under the 50% level, despite some showers in recent days.
Water restrictions came into force in Whangarei on Thursday evening, with bans on hose use and commercial car washing, until further notice.