The costs of Sunday night's flooding are expected to be significantly more than the $16.8 million total from the December 2011 floods, insurers say.
Torrential rain from 5pm on Sunday caused havoc in Richmond and Stoke, turning roads into rivers and flooding homes and businesses. The downpour dumped 104 millimetres of rain on central Richmond in an hour.
Many businesses, particularly in the Wakatu Estate, are closed, with owners now assessing the damage, and many residents are cleaning up the mud and debris in their homes.
The Nelson-Tasman Region Civil Defence and Emergency Management Group has now stood down, and each council will now deal with issues raised by the flood in their own districts.
Saxton Field and the fitness centre at the ASB Aquatic Centre suffered significant damage, and will be closed for at least a week. All sportsgrounds in Nelson and Tasman are closed, along with Rabbit Island, Easby Park Playground, and Dellside Reserve.
There is also a boil water notice for council reticulated and personal bores in Motueka, and people are advised not to to take shellfish or swim off Tahunanui Beach due to a sewage overflow from Bells Island.
In all, 10 families had visited the welfare centre seeking assistance, and that centre has been closed now as well. About 70 homes were evacuated.
Nelson City Council had received 700 requests for sandbags by yesterday afternoon.
Insurance Council of New Zealand chief executive Tim Grafton said the council estimated there had been between 1200-1500 claims so far.
All indication suggested the event would be larger in terms of costs than the December 2011 floods.
Insurance manager John Lucas said after speaking to insurance assessors, there was no doubt the flood would be more expensive than the 2011 event. Those floods produced an insured loss of $16.8 million.
"The [Sunday] event was short and sharp but it has created a lot more widespread damage," he said. He expected more claims to be lodged today and tomorrow.
Those without insurance are advised to contact the Ministry of Social Development in Stoke or Nelson.
Dr Smith said he had visited homes and businesses yesterday and estimated the insurance bill from the ones he had seen would have been getting close to $10 million.
He would be helping those families whose houses were hit in the flood.
Some families did not have insurance so they would also be under huge financial pressure, and he would be working with them to do what he could to help them.
The standard of the drainage systems in the badly-affected areas needed to be assessed, he said.
"While it was a weather bomb that hit the area some of those properties have been hit previously, and we probably need to invest in extra drainage so that doesn't happen again.
"We need to get the hydrologists and drainage engineers to check some of the worst affected suburbs, so that if there is insufficient infrastructure that we get in and fix it before these poor people get hit again."
Tasman mayor Richard Kempthorne said it was unlikely the council would bring forward any stormwater upgrades as a result of the flood.
"This does highlight the need for it, but we have yet to talk to business owners about their share of the cost and we are not going to do that until we have the figures in place."
The storm also highlighted stormwater "pinch" areas around Champion Rd, he said. Mr Kempthorne said he was comfortable with the council's stormwater planning around its long-term urban and business growth around Richmond.
Although more climate change-driven storms were predicted, Mr Kempthorne said it would be unaffordable to build a stormwater infrastructure system to cope with such rainfall. The key was being able to respond immediately, he said.
Landowners also needed to look at risks on their own land.
It was too early to put a figure on the cost to council infrastructure, but the council's roading or drainage networks had not been severely affected.
It was possible the council's disaster relief fund, which sat at $1.23 million at December, could be used for any repair work, he said.
But the council would not have access to the national Civil Defence disaster fund as no civil emergency was declared, he said. He also doubted the flooding would harm the local economy to any great extent.
- © Fairfax NZ News