Water pumps are running throughout Christchurch, after heavy rain and a king tide caused flooding this morning throughout the city.
The city council deployed the pumps yesterday in areas including flood-prone Flockton and Southshore, ahead of the expected bad weather.
Parts of the city, particularly along the Heathcote River, regularly flood during heavy rain.
Christchurch City Council spokesperson Tim Joyce said all of the pumps were turned on about 3am today as the heavy rain began and were keeping most of the flood water at bay.
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However, Mr Joyce said some areas were still flooding, including parts of the Heathcote River, Southshore, and Main South Road.
On Maces Road, a pump was "struggling" to keep up with the volume of water.
"Down in the lower reaches of the Avon and Heathcote [rivers] there is flooding along some of the roads, as we usually experience," he said.
MetService expected about 36mm of rain to fall in the city today.
Mr Joyce said the council had received many calls this morning from affected residents, and council staff were out unblocking drains and keeping an eye on water levels.
He said the rain was expected to ease later today, and people needed to stay put and wait it out.
"Don't travel if you don't have to and keep off the flooded roads."
He did not think the flooding would get worse, and did not expect water to reach homes.
"The tide is going out and the water will recede."
The wild weather had also closed State Highway One north and south of Kaikoura, with an inland route on State Highway 70, the only open road into the seaside town.
Rain welcomed in dry spots
Meanwhile, other South Island districts have welcomed the rain.
Hurunui Mayor Winton Dalley said between 15mm and 40mm of rain had fallen in the district today, topping up water supplies and giving firefighters a break.
Mr Dalley said the district had been very dry, with a few fire "scares", but today's rain would help dampen down dry land.
"There has been a few fires already, so this change of temperature and moisture will be very welcome," he said.
At the start of summer, parts of Hurunui were under water restrictions, with authorities especially worried about Hanmer Springs' water supply.
Mr Dalley said even though water levels were never critically low, today's rain would take some stress off supplies during the busy holiday period.
The Transport Agency are warning South Island motorists to be careful.