Severe floods cut off road and telecommunication networks around Te Anau, and "off the scale" weather conditions forced the evacuation of 120 trampers from the Milford Track yesterday.
Southland District Mayor Frana Cardno said the rain was the worst she had experienced since moving to the town more than four decades ago, with the Upukerora and Whitestone Rivers turned into "raging torrents".
Mrs Cardno said flooding prevented her from attending a meeting in Invercargill, and contact with her council was made impossible when all lines of telecommunication went down shortly after 1.30pm.
Damage to the Whitestone River bridge on State Highway 94 resulted in cabling being washed away, cutting off landline, cellphone and email links to the town.
Witness Nigel King, of Te Anau, told One News there was an "almighty bang" when the bridge carrying the fibre optic cable was destroyed by the torrent.
About 2000 Te Anau residents were able to make landline calls within the Te Anau exchange area, including local emergency services, but were unable to make or receive calls to numbers outside of the exchange area.
Landline services were restored last night.
Department of Conservation (Doc) programme manager Ross Kerr said heavy rain since Friday had caused major flooding, washing out at least one bridge and compromising other structures.
Milford Track trampers had spent two nights inside huts but food began to run low yesterday, so an evacuation operation was launched.
Trampers were flown by helicopter and taken to the head of Lake Te Anau where two Real Journey boats transported them to Te Anau Downs.
Mr Kerr said the monitoring data coming in electronically for the Clinton and Arthur Rivers on the Milford Track, and Cleddau River in Milford Sound was "off the scale".
Doc recorded 739mm of rain having fallen in the three days until 8am yesterday at Dumpling Hut on the Milford Track.
Queenstown weather recorder David Crow said 67.6mm of rain fell in the 24 hours to 9am yesterday, the heaviest daily downpour in the resort since September 2002.
He said Lake Wakatipu was at 310.76m yesterday, just "knocking on" its first flood warning level of 310.8m.
Toni Glover, of Glenorchy's Kinloch Lodge, said 105.1mm of rain fell in 24 hours to 9am yesterday.
The Dart River was at 1300cumecs, its highest level since 1996, she said.
The Paradise Rd was also closed.
Eleven lodge guests were escorted out in a convoy via roads which had surface flooding.
Environment Southland spokeswoman Michele Poole said swaths of farmland in the Te Anau Basin were already underwater, with extensive damage to fences and other infrastructure.
Environment Southland and Civil Defence staff were on duty through the night to monitor river levels.
