Flooding forced the closure of the SH1 bridge over the Ashburton River on Sunday. Photo: Ashburton District Council
A bridge on State Highway 1 in Ashburton has reopened as heavy rain eases, but motorists are warned to take care with surface flooding on many roads.
The bridge over the Ashburton River in Canterbury had been closed overnight, reopening at 6am.
There has been widespread surface flooding across the Canterbury Plains, with some places getting a month's worth of rain in a day.
MetService meteorologist John Law said the heaviest downpours were in Banks Peninsula, with 240 millimetres of rain in the 48 hours to 6am, while in Ashburton, 120mm fell.
Boil water notices were issued for some parts of the region.
A specialist team rescued a man stuck on the roof of his car in a flooded ford in Canterbury on Sunday night.
Fire and Emergency was alerted about 10.30pm to a man who had been stuck on the roof for some time in the Hawkins River.
Fire crews from Darfield and Kirwee and a swift waters team from Christchurch were sent. The man was assessed by ambulance staff after he was rescued.
Ashburton Mayor Neil Brown said floodwater was flowing over the land, but the river level did not get as high as it did in major flooding in 2021.
Waka Kotahi said the bridge closure had been precautionary given the build-up of flood debris around the piers. The bridge was damaged in flooding in 2021.
"It was a very precautionary approach, I would accept that, it's not something we take lightly but the flows weren't subsiding as quickly as we had hoped in the afternoon," spokesperson Mark Pinner said.
Contractors were checking roads in the Ashburton district and the council warned there was still widespread surface flooding.
MetService orange heavy rain warnings had been in place for Canterbury and eastern Marlborough south of Ward through to 7am on Monday.
The worst of the rain was over by early morning, Law said.
Conserve water
Residents in Selwyn district will have to conserve drinking water for some time after the heavy weekend rain, mayor Sam Broughton said.
Some rural water supplies rely on taking water from rivers which have become muddy due to flooding, so the water cannot be used.
"We've got storage which will see us some of the way, and households on those supplies have their own storage on-farm or in their house too, so we're just asking people to conserve that."
Four people from Selwyn Huts were evacuated as a precautionary measure, he said, because that community would become isolated if the river burst its banks.
Elsewhere in the region, Tuahiwi residents living near the Cam River had been urged to stay with friends or family overnight because of rising waters, and at least eight families sought shelter at a Civil Defence Centre at the Riverside Church in Kaiapoi.
State Highway 79 between Fairlie and Geraldine was closed between the Gudex Road and Maxwell Road intersection because of flooding.