Welfare teams will go door-to-door in the most quake-affected areas on Tuesday, a day after the magnitude-7.5 shake that was felt around the country.
At the top of the South Island, the town of Ward was hit hard. A number of buildings have been badly damaged and roads into the coastal area have been destroyed.
Residents are also having to contend with regular aftershocks, centred in nearby Seddon.
Red Cross spokesperson Chris Stuart says many people in Ward and towns like it will run out of food this morning.
"The first team who have gone into Ward will come back and brief us on what the actual needs are, [as] communication has been a bit of an issue," she says.
"We have actually sent up quite a lot of water [and] we've got enough food supplies for the people. We will then be assessing what their ongoing needs are."
The Red Cross is appealing for any donations to help provide aid.
And they're not the only ones helping out - with a group of young tradies from Blenheim is offering a helping hand to quake-affected residents in the South Island as well.
Tyler Fifield says after the tremors hit, he and his friends decided to find people to help.
"We've got skills and gear and everything we needed, so we jut chucked a heap of stuff in the back of the truck and just headed down and mucked in wherever we could to get their house liveable again," he says.
Mr Fifield says he's well aware of how much needs to be done.
"It'll take years for people to get everything back together," he said.
"Many of the buildings we're called in on are potentially over 100 years old, and there's been generations of families live in these houses that are just wiped out in one hit."
Anyone impacted by the quakes and in need of maintenance work can contact Mr Fifield and his friends on their Facebook page.
Newshub.