"It could be cloudy or milky and once the problems are fixed it might take up to 24-hours for that cloudiness to disappear."
Dannevirke South and Huia Range Schools and Totara College have made the decision to close today , but Dannevirke High School and St Joseph's School will remain open.
Debbie Max, principal of Totara College, said her school had been told too late of the option to have a water tanker.
"That notice came after we'd informed everyone we were closing," she said.
The Tararua District Council would have a water tanker in place at the high school and students had been told to take water bottles to fill.
"All schools follow the appropriate processes themselves," Maxwell said.
Sheryl Berry the administrator at St Joseph's School, said they are "quite confident" they can manage the situation.
"We have taped off all our drinking fountains and children have been asked to bring their own bottled water tomorrow. We will also have spare water bottles for those who don't," she said. "Notices have also gone home to parents explaining the situation."
Maxwell said the council is working according to its water safety programme which is aligned to Ministry of Health requirements.
"This is not a E.coli outbreak. It's just that he quality of the water has been reduced and we have to manage any risk," he said. "The boil-water notice has been put in place as a precaution and water going through the treatment plant is being chlorine dosed."
Maxwell said council is hoping the problems will be sorted today.
Boil your water:
*Until notified, Dannevirke residents are advised to boil water before using it for drinking (including making of sachet juice/drinks), making ice, food preparation, brushing teeth and preparing infant/toddler formula.
* Electric jugs with a cut-off switch can be used as long as they are full – allow the water to come to the boil and wait for it to switch off (do not hold the switch down to increase the boiling time). Water can also be placed in a clean, metal pan and brought to a rolling boil for one minute. Boiled water should be covered and allowed to cool in the same container.