Specially trained staff from dairy co-operative Fonterra have joined the recovery effort in Christchurch city centre.
Fonterra national emergency response leader Kevin Lockley said 24 personnel were working in the city alongside regular teams.
Fonterra has 160 employees available in its emergency response team.
"[They] come from military, navy, fire service, ambulance service, search and rescue - we've got 'em all."
Fonterra has plans for emergency preparedness on each of its sites, emergency response and business continuity.
The company's Clandeboye plant team took care of the co-operative's local milk powder plant after the earthquake.
"We can take care of the initial response until we get back up from outside services, that's what it's all about."
Lockley's team had been on standby since day one and deployed last week.
"We're working under the Civil Defence umbrella ... we give them our skill level then they come back to us and said deploy the two teams of 12 on Tuesday ready to start."
Lockley's team did not undertake the duties of specialists who had arrived from overseas but had been checking buildings, rubble and escorting structural engineers.
"The overseas deployment and the local teams that are in here are just blown away that Fonterra has that capability," Lockley said.
The team had pitched its tents in a park. "We're self-sufficient, so we weren't reliant on the community for services, we come completely independent as a team to live, eat and look after ourselves."
The earthquake was the biggest event with which Fonterra's emergency response team had been involved, Lockley said.
"It's huge, it just looks like someone's dropped a bomb on the place. Hard to describe really, it's in pieces."