Porirua residents and businesses are being warned to save water after a water main ruptured in the suburb of Whitby.
The Greater Wellington Regional Council and the Porirua City Council are trying to find the site of leak which is in an area where two water mains run next to each other.
It is estimated there is enough water to last about 12 hours a day.
The regional council's water supply general manager, Chris Laidlow, says Whitby, Pukerua Bay, Plimmerton, Paremata and Ascot Park will be affected and people must conserve water until the leak is fixed.
Repair teams will be working through the night to try and isolate the problem.
