Landslips blocking the coastal road to Kaikōura could take months to fix, and it is still unclear when the inland road will be open to the public.
The small town was cut off by last Monday's devastating 7.8 magnitude earthquake in the upper South Island.
View RNZ's full coverage of the earthquakes here.
Army convoys have begun daily supply trips on the inland road, with the first trucks making it through on Friday and a second group on Sunday, and there was limited access to the road for some residents today.
Parts of State Highway 1 north and south of Kaikōura remain completely blocked by slips.
The east coast railway line was also badly damaged, with the rails bent and twisted by the force of the earthquake, and tracks covered by landslips.
At a town meeting this afternoon, officials told a frustrated crowd that the inland road would not be open to the public before the end of the week.
Civil Defence controller Murray Sinclair said opening a ground route out of the town was a priority, and a permit system would be established once the inland road was given the all-clear.
Civil Defence was working out how many people wanted to leave Kaikōura, in the event emergency flights were needed, he said.
The New Zealand Transport Agency (NZTA) said it would be several months before SH1 between Christchurch and Picton was re-opened.
Spokesperson Mark Owen said a number of the slips on the road were as large or larger than the one that closed the Manawatu Gorge in 2011.
He said those slips were still too unstable for geotechnical engineers to go near at the moment to inspect.
"Those inspections will take time, and until those inspections have been carried out, it is too early to say what techniques will be employed to clear these slips, how long the work will take, or how much it is likely to cost."
Mayor Winston Gray said a free bus shuttle service would open tomorrow in the area, and he urged people to carpool because of a fuel shortage.
Evacuees make their way back
Locals who evacuated after last week's quake were being escorted along the inland road towards Kaikōura, but might not be able to get beyond Mt Lyford.
Civil Defence was allowing residents, road and power repair contractors in four-wheel-drives or heavy trucks to make the trip from Waiau. Farmers were also being allowed to deliver water and retrieve milk.
The army was escorting convoys of residents from Waiau at 10am and 2pm.
Civil Defence said access along the inland road would be restricted beyond Mt Lyford, because there were still significant hazards on the road.
Civil Defence spokesman Ken Taylor said geotechnical specialists were assessing the safety of the road this morning to see if residents could go beyond Mt Lyford.
"That assessment will be made by the NZTA people, once we get the information from the geotech specialists who are in the air at the moment."
Mr Taylor said large slips, collapsed culverts and unsafe bridges made the road hazardous and he had no idea when the road would fully re-open.
Authorities said no other civilian trips along the road would be allowed and all the plans were subject to good weather and no further hazards, such as landslides.
No towing vehicles would be allowed on the road.
At this stage, farmers in Kaikōura would not be able to get their milk out and would have to continue dumping it.
Schools stay shut for the week
Problems with sewerage and water, meanwhile, are keeping the town's schools and early childhood centres shut.
A spokesperson for the town's education services, Richard Cotter, said they would have to stay closed until they could be confident that they could provide a hygienic environment.
Mr Cotter said they would meet on Thursday, and should have a better idea about when they might open then.
Most of the organisations suffered little structural damage in Monday's earthquakes and the subsequent strong aftershocks, he said.
But they could not re-open until they had working toilets and fresh water.
"Hygiene is the real issue at the moment, along with some that don't have power at this point. So we can't open until we can be confident the hygiene of the schools is up, and also the key concern for us is the welfare of staff and students."
There are four schools in Kaikōura and two others near the town.
Kaikōura High School principal John Tait said concrete block cladding has to be taken off all its buildings, and replaced with ply.
The gym could not be used and some other buildings also suffered damage, he said.
Fire ban put in place
A total fire ban is now in place in Kaikōura. The area has been under an open season, where fire permits are not needed, and usually moves to a ban after Christmas, but a decision has been made to bring that forward due to the short supply of water and fire-fighters.
The ban covers South Marlborough to the Hundalees.
The principal rural fire officer for Marlborough and Kaikōura, Richard McNamara, said crews had been called out unnecessarily in the past week since the quake.
"We don't need nuisance rubbish fires, we don't need crews turning out to calls at night because somebody has seen a fire off in the distance, where it's just a burn pile burning down. The most valuable resource we have right now is our volunteer time and we need to keep it in check for the response to the quake."
But Mr McNamara said people needing open fire to cook food were exempt from the ban.
'Challenges' in getting supplies into town
Another convoy of six trucks loaded with groceries and fuel made it through yesterday - the second army convoy in 48 hours. It is taking the convoys about three hours to travel from Culverden to Kaikōura.
Colonel Glenn King said getting supplies to the town had been a big challenge.
"We've had to rely on our ships and our helicopters, and that's created some challenges. And once you've got them into Kaikōura, it's then a challenge for the emergency operations centre and staff here is getting them out to everyone who needs it."
Colonel King said the priority was to get food, water and equipment for power into Kaikōura as quickly as possible.
In the past week more than 500 soldiers, sailors, air crew and support staff have been involved in the recovery effort, along with 11 aircraft and four vessels.
The navy ship Canterbury is on standby in Lyttleton, in case it is needed again to resupply Kaikōura.
Joint Forces Commander Major General Tim Gall said the Canterbury needed to be rested in case it was needed for another emergency.
"We need to give the Canterbury and the helicopters a bit of rest and maintenance. We've got a significant chance of another aftershock, and it would be terrible not to have that stuff in the back pocket when we needed it."
Major General Gall said the international ships had left Kaikōura for Auckland to be part of the navy's 75th anniversary.