Lyttelton Port was one of many Canterbury companies counting the cost of the earthquake last night.
The port received major damage, said chief executive Peter Davie.
The epicentre of the magnitude-6.3 earthquake was near Lyttelton at a depth of around 5km, according to reports.
"[The damage] is bigger than last time, but what the recovery programme is we don't know yet," said Davie, who was making the first walkaround of the facility when the Business Herald contacted him last night.
He said none of the staff had been injured and it was not clear how long the port would be closed.
"At this stage we'll say 24 hours ... and we'll go from there."
Last September's earthquake caused a lot of damage to the port, which moved 9.8 million tonnes of cargo in the year to June 30, 2010.
Skellerup acting chief executive David Mair said the Christchurch-based farming equipment manufacturer would have to airfreight its exports if the port remained closed for long.
"My primary focus at the moment is simply making sure our staff are okay."
He said none of the Skellerup staff had been seriously injured.
Fletcher Building was yesterday assessing the damage to its operations.
Although the company won the main contract to manage the recovery operation from the September quake and stood to gain financially from last year's disaster, yesterday it said its businesses in the city had been damaged severely at some bases.
Lion Nathan corporate affairs director Neil Hinton said late yesterday he was unclear about the situation in the firm's Christchurch brewery.
"We're certainly in the area where there is some damage but we're just not sure what the extent is," Hinton said. "Nobody is injured and everyone on the site is okay ... the guys that were at work are being sent home to look after their families."
He said the brewery would be shut down for at least two days.
"The last thing we're thinking about right now is brewing."
Sanitarium general manager Pierre van Heerden said the cereal maker's Christchurch manufacturing facility had mostly escaped damage, and its staff were uninjured.
The Sanitarium plant in Papanui Rd was being used as a triage centre and van Heerden understood people in the area had been hurt in the quake.
Sanitarium had shut its Christchurch facility down yesterday afternoon and given its staff of around 60 the rest of the week off, van Heerden said.
"There are a number of our staff who are going out to assist with the relief efforts and assist others in need."
Progressive Enterprises said that all Countdown supermarkets in Christchurch were closed last night, while online shopping operations had also been suspended.
Foodstuffs - which operates Pak 'N Save, New World and Four Square stores - said that it had not received any reports ofdeaths or injuries in its Christchurch operations.
"A number of our supermarkets are open where people can obtain water and essential items," said Foodstuffs managing director Steve Anderson.
- Additional reporting: Owen Hembry, Anne Gibson