Heavy rain has closed Christchurch roads, while houses at Pleasant Point were evacuated when damage to a river stopbank posed a flooding risk.
The Avon River in flood in central Christchurch. Photo: RNZ / Nathan Mckinnon
Christchurch
The Avon River burst its banks in central Christchurch after heavy rain, forcing the closure of Oxford Terrace from Barbados Street to Willow Street.
A slip closed Dyers Pass Road beyond Summit Road.
Drivers are also being urged to take extra care on SH73 at Yaldhurst Road where there is significant flooding.
The city council is warning there could be debris on the roads.
On Banks Peninsula, Marine Drive in Diamond Harbour is also closed due to power lines being down.
Meanwhile more than 300 people are without power in Lyttelton, after extreme weather brought down power lines.
Electricity lines company, Orion, says the outage began just before 2.30am and is affecting homes in Diamond Harbour, Charteris Bay, Church Bay and Hornby.
Just before midday, 150 homes in Birdlings Flat and Little River also lost power.
Orion estimates power will be restored in the next few hours.
Photo: RNZ / Nate McKinnon
Pleasant Point
Timaru District Council declared a state of emergency for the Pleasant Point-Temuka ward because of a risk of flooding.
A damaged stopbank on the Opihi River through Pleasant Point was deemed a flooding risk. Photo: Supplied / Timaru District Council
About 15 people at Pleasant Point were evacuated with help from police and security was put in place, the council said.
Environment Canterbury river manager Leigh Griffiths said a stopbank at the south end of the Opihi River had been damaged following heavy rain.
Most left last night but one or two "needed a bit more encouragement" to leave, Griffiths said.
"Until we can assess that stop bank this morning and carry out necessary repairs it's possible they won't be allowed back, so the Timaru District Council made the decision to declare an emergency just to have additional powers for themselves and police."
Extensive scouring of the stopbank posed a flooding risk with potential to be a threat to life and property, the council said.
"We're getting engineers on site to see what temporary repairs could be undertaken" - Environment Canterbury river manager Leigh Griffiths
The river level was dropping, but as it fell the water could change direction and break through the gap in the stopbank, Griffiths said.
"It's not as I understand it a significant flood path but it obviously does affect some people in their homes."
About 10 people were evacuated from their Mill Road homes due of the risk of the floodbank failing.
Timaru Civil Defence controller Paul Cooper said all residents left voluntarily initially, but two changed their minds during the night.
He said a state of emergency for the entire ward was the only way to forcibly evacuate them.
Cooper said the raging river eroded two metres of the stopbank yesterday and there were real concerns for life and property.
Those evacuated will be out of their homes for up to five days.
Timaru deputy mayor Steve Willis said the state of emergency was to ensure residents didn't re-enter their properties unsafely, and that other people didn't breach the cordon.
It may be another day or two until the stopbank could be fully assessed, he said.
"Everyone's followed the directions given to them, but we had some concerns about people breaching the cordon and that also puts at risk our other emergency personnel and volunteers. So what we're trying to do at the moment is encourage people to stay away from the area just to make sure everyone's kept safe."
Stopbanks had taken a bit of a hammering with flooding over the past few years, Willis said.
Heavy rain and strong wind watches are in place for the region until this afternoon.
There had been erosion damage to stop banks on the Ashburton River as well, but it was not threatening any homes and the water level had dropped, Griffiths said.
Waitaki District
Essential supplies were dropped off in Lake Ōhau village in the Waitaki district overnight.
Some road access to Lake Ōhau village is expected to be restored tomorrow.
Flooding washed out a bridge near SH8 on Tuesday morning, trapping residents and holidaymakers.
Lights vehicles are expected to be able to get in and out of Lake Ōhau village from tomorrow.
Waitaki district mayor Gary Kircher said light vehicles would be allowed to use the bridge first, and the structure would be monitored before heavier loads were allowed.
A digger at the site of repairs to the Lake Ōhau road. Photo: Supplied / Waitaki District Council
Flood levels have dropped and the weather has improved, which the district council says is allowing contractors to make good progress on repair work.
Several other roads in the district remain closed due to flooding, washouts and landslides.