More than 100 properties have been red-stickered after days of torrential rain and slips in the Nelson-Tasman region last week, and some will have to be destroyed.
Nelson Tasman Civil Defence spokesman Chris Choat said it was likely this number would go up once inspectors made it to the most inaccessible areas.
"We've got houses on land that is moving, and so ... we have to tell people they're not allowed near their house for some time or they can go back on a restricted basis ...
"You've seen the pictures, there will have to be some demolitions.''
Teams of building inspectors, geotechnical engineers and welfare officers hoped to complete the second phase of inspections within the next three days.
They would try to allow affected residents some access to their homes in that period.
Mr Choat said the operation was now starting to move from the response to the recovery phase as the water began to subside.
"There are still places that are cut off and where people need food dropped in, but we are moving into the next phase, thinking about what we're going to do with the damaged roads, the infrastructure and displaced people.''
There had not been a great demand for emergency shelter, other than a few people staying at a Tasman marae, because most affected residents had stayed with friends, family or at motels.
Meanwhile, contractors are working to ensure water supplies are secure in the waterlogged area in time for the holiday season.
Slips have cut off the water supply to Pohara Valley in Golden Bay, while the main water pipeline to Nelson has been threatened by several slips.
Nelson Tasman Civil Defence controller Jim Frater said more than 300 slips were being monitored, particularly those in built-up areas, with some still moving.
"We're keeping an eye on the weather and towards the end of the week it looks like we could have some more bad weather, and while the land is in that position, there is still a potential for further slipping,'' he told Radio New Zealand today.
The Pohara Valley water supply had been almost completely wiped out, but was expected to be up and running again by Wednesday.
The No.1 priority was the Maitai Valley pipeline that services Nelson, which had suffered damage from several slips.
"It's particularly important because we've got a holiday season coming through and the last thing we want ... is to be water rationing.
"We have asked people to conserve water in the Richmond area because there has been a pump that has electrical problems, and that's affecting our ability to pump to other areas.''
If the Maitai pipeline did fail, water would be have to be pumped from Richmond.
Nelson Mayor Aldo Miccio told Radio New Zealand this morning the water situation was still precarious.
A weekend helicopter flight found there has been about eight slips under the Maitai pipeline.
"We've had engineers walk the entire length of the actual pipeline and there has been a couple of spots that are a threat if there are further slips, but the rest is stable and we are getting workers up there to stabilise weak spots.''
Mr Miccio said there were contingencies in place, with secondary dams stocked with water just in case the pipeline is broken.
Another 30 homes were evacuated from Grenville Terrace above Rocks Road in Nelson yesterday as the ground continues to move, days after the deluge.
About 100 residents remain cut off following a slip at Cable Bay. Supplies are being airlifted in, while Civil Defence hopes access can be opened up to the settlement within a week.
The state of emergency is in place until at least midnight Tuesday, although it is likely to be extended a further seven days.
