The West Coast town of Haast was cut off in the aftermath of Cyclone Fehi leaving 700 people stuck in the township and 115 motorists stuck near Fox Glacier.
The large-scale wreckage from severe weather included the destruction of a house and church in Haast, while further south a bridge had collapsed in Gore.
Bruce Bay Marae had been evacuated and the evacuees were now also in Haast.
Westland District Mayor Bruce Smith said there had been a massive slip, almost 100 metres wide, at Douglas Bluff blocking access to Haast from the south.
There was also severe damage to the access road to Fox Glacier, he said.
"There are 700 tourists all in Haast wanting to go south or north and they can't go either way."
Mr Smith said they were relying on a limited supply of power.
"Our emergency response team has worked brilliantly."
The people stuck in Haast had all been provided with beds and food, he said.
"The hospitality in South Western is unbelievable."
All of SH6 from Ross through to Haast Pass was closed.
The stretch between Fox Glacier and Franz Joseph would remain closed overnight as a 30-tonne digger was needed to clear the slip at Omoeroa.
Our Lady of the River church, located about 38km from Fox Glacier on Haast Highway, was completely destroyed by wild winds and flooding.
A man who lives nearby, who did not want to be named, said the small church looked as though the wind had "picked it up" and "chucked it on the ground again".
He said not long after the church collapsed Jacobs River (Makawhio River), which was located nearby, burst its banks causing water to go right through what remained of the building.
A boil water notice was in place for Arahura while all areas were on conserve water notice due to network vulnerabilities.
In Hokitika 700 consumers were without power as several transmission pole structures suffered significant damage.
Buller Civil Defence had issued a warning today advising parents to keep children away from playgrounds near flood water due to contamination, especially in Carters Beach and Granity.
The state of emergency in Dunedin was lifted at 8.30am today and the Emergency Operations Centre will close this afternoon.
Dunedin City Council teams had visited about 11 properties to assist with flooding issues.
Radius Fulton rest home in Caversham would require significant repairs and the residents had been relocated.
The Mayoral Relief Fund had been relaunched today to help any residents badly affected by yesterday's flooding.
Most roads had been reopened but Ruskin Terrace and Edwin St were closed due to sewage contamination and Hoopers Inlet and Papanui Inlet were closed due to surface flooding.
Fire and Emergency NZ had more than 228 weather-related calls across the country yesterday, 210 of which were in the South Island.