Checkpoints
Geotechnical engineers advised Kaikoura Civil Defence that given the size of the dam and the weather forecast there was a risk it could breach.
Sinclair said they were hoping the water would gradually build up, go over the top and slowly cut its way through without a sudden surge spilling over the top.
But they could not be certain it would not burst so public safety was paramount and homes in the potential flood path evacuated.
Residents have been told to be prepared to be gone for at least 10 days while Civil Defence monitors the dam.
Evacuated Goose Bay Campground owner John Mahony briefly returned to his deserted property today to feed his pets.
He said the weather was starting to turn but at this stage the creek at the centre of yesterday's scare was running clear and at normal levels.
Mahony, who described the evacuation as a "pain in the neck", said heavy rain was needed to fix the problem.
"The powers that be need to send around three inches in a couple of hours and it would sort out the slip," he said.
He said many living in the holiday settlement were aggrieved at the sudden evacuation.
"A lot of us live 100m up the hill from the creek, and we're a bit pissed off we can't stay but hey, we'll go."
"But you've got to do what you've got to do, when you've got to go you've got to go," said Mahony.
"Basically we were told that we have to go because this thing might burst."
He said they've been given no definite timeframe for when they will be able to return home.
"They don't know, they've got no idea really. It could be a couple of days, could be a couple of weeks, whenever.
"We're just sitting around a bit and answering the phone because that's going flat out, and packing up a bit."
Mahony said he would stay with mates nearby.
"We're just going 500m around the corner to a friend's place, so we're not going far. And there's a few people who are going to camp at the harbour a few kilometres up the coast."
Goose Bay bach owner Cushla Twist, speaking from her home in Christchurch, said she was annoyed that the evacuation of the seaside community had been publicised because looters might now be attracted there with the knowledge the houses were empty.
"We've asked for a 24-hour manned roadblock coming into Goose Bay."
Civil Defence's Charlotte O'Sullivan said evacuees would be staying with friends and family, or given accommodation.
"We have heard that everyone was understanding of it. Bad weather is coming and it could breach so and it's in their best interests to evacuate. They all understood."
"The geotechnical engineers will keeping an eye on the size of the dam and the forecast, and then just basing it on the risk factor."
O'Sullivan said Civil Defence welfare teams would stay in touch with evacuees, as more information came to light.
There have now been more than 5000 quakes since last Monday's massive 7.8 quake.
GeoNet says there had been 5120 aftershocks with 153 tremors in the past 12 hours.
