The coastal highway between Paekakariki and Pukerua Bay was blocked by a 40 cubic metre slip at 7am this morning, forcing motorists on either side to turn back. The alternative route, the Paekakariki Hill road, is also closed because of debris on the road.
The northbound lane of the coastal highway opened intermittently from late morning.
"The tail of the slip was on one side of the road. We're going to move it to the other, which means we can get all the trucks that are parked up and backed up behind the slip through," Transport Agency spokesperson Mike Seabourne said.
More than 100mm of rain has fallen at Paraparaumu Airport, flooding local waterways and forcing the airport to close.
SH1 north of Paekakariki becomes an almost deserted highway due to rain and flooding pic.twitter.com/AbGmZ0zTy9— Gareth Thomas (@rnzMaorinews) May 13, 2015
Eighteen Kapiti Coast homes have been evacuated, mainly in Raumati where the Wharemauku stream has breached its banks, and the Kapiti District Council warns there could be more evacuations following tonight's rainfall.
The Kapiti District Council says the Waikanae River has exceeded its 10 year level after slips closed State Highway 1 and halted trains. It says it's concerned that the river will rise even higher with this evening's rain coinciding with a high tide.
The Wellington Free Ambulance said it was using four wheel drives to get paramedics to people stranded by the floodwaters in Kapiti.
It said it was fully equipped to deal with the emergencies on the Kapiti Coast and was working closely with the regional emergency management operations to stay up to date.
Floodwaters spilled into Glenn Wickert's Paraparaumu property.
"The water has dug out under the retaining wall and fence," he said. "It's washed the top layer of my lawn off, and has deposited large rocks, bricks and general debris further along my property."
Paraparaumu resident Shane O'Donnell said one of the streams looked like it was flowing faster than the Waikanae River. "It's very very fast and aggressive. I have never in 30 years seen it anything like this."
Eighty-year-old Paraparaumu resident Jill France said she was woken by the sound of the water, and the creek behind her house had turned her yard into a swimming pool.
"I haven't had this flooding around here for it must be 12 or 14 years - it's quite a long time," she said.
"I've got the creek running at the back (of the property) and that's really quite up as well. It's quite exciting."
Ms France said the water had gone into her basement.
A Fire Service spokesperson said it had responded to 15 calls regarding flooded houses in Paraparaumu and Raumati this morning.
Schools closed, evacuation centre set up
An evacuation centre had been set up at Paraparaumu's Community Centre, and the police were knocking on doors in the worst-hit areas to assess the damage.
Kapiti Coast Council spokesperson Anna Kenna said most of the people who had been evacuated were staying with friends and neighbours but a second evacuation centre was on standby in Raumati as more heavy rain was expected tonight.
People to stay off the roads and out of the floodwaters as they could be contaminated with sewage, she said.
Wellington Free Ambulance activating back-up plans while State Highway 1 was closed.
Head of operations Rob Ives said there was one ambulance and one urgent community care vehicle, and extra ambulances were being brought in. Paramedics who could treat people at home were operating from Paraparaumu.
The weather disruption affected schools in the area, with Paekakariki School, Raumati Beach School, Pukerua Bay School, and Paraparaumu closed. Kapiti College will supervise any students who turn up but will not be teaching due to lack of staff.
Tamara Savage was at Paraparaumu heading for Wellington early this morning and told Morning Report the conditions forced her off the road.
"I was driving through water deeper than my knees," she said.
"I've only got a little Suzuki Swift and I was actually aquaplaning, only doing about 10 [kilometres an hour].
"A huge slip come down off the hillside and it came right across into the northbound lane, but I managed to get past it by driving up on the footpath."
Radio New Zealand producer Chris Reid was on the highway north of Paekakariki, and said water was up to one metre deep and there are many slips on the hills.
"Many of the cars are giving up and trying to reverse back up an on-ramp ... to try and turn around and go back."