Fresh water is being trucked to rural communities in the Canterbury region whose water supply has been contaminated by the heavy rainfall.
Water is being supplied to Akaroa, Takamatua and Duvauchelle after more than 66 millimetres fell in Canterbury since Sunday.
The Christchurch City Council says the heavy rain has caused stormwater to mix with clean stream water and is urging all Banks Peninsula residents to conserve water as supplies are running low.
There is flooding in a number of locations around Christchurch and one of the worst effected areas is the suburb of Mairehau.
Meanwhile, a school in Christchurch is closed on Monday due to flooding.
Christ the King Catholic School's foyer and library have been flooded and the grounds were under about 15 centimetres of water.
Principal Mike Bonisch said hopes the school's 340 pupils can return on Tuesday. Most parents were informed on Monday by the social networking site Facebook and email.