Lake Wakatipu is not expected to flood Queenstown CBD over the next few days despite torrential rain.
Queenstown Lakes District Council is keeping a watching brief on lake levels. The level is expected to reach the first flood warning trigger point of 310.8 metres this afternoon (Wednesday).
Modelling carried out by Otago Regional Council (ORC) suggests the worst case scenario is lake levels reaching the second trigger, 311.3m, tomorrow afternoon.
That could see minimal flooding in low-lying reserve areas such as Queenstown beach, Frankton arm and St Omer Park.
But lake waters would need to rise by about another metre before CBD businesses are threatened. The 1999 flood level was 312.8m.
“Our second indicator level – 311.3m – is referred to as ‘possible flooding’, but that means nothing more than ponding in low-level reserve areas,” council communications boss Meaghan Miller says.
“It’s still a significant way off any issues in terms of threatening property or anything of that nature.
“It’s an awfully big lake and takes a lot of rain to fill it. That’s the unscientific response but fortunately we also have scientific modelling by Otago Regional Council.”
Glenorchy-Paradise Road from Dan’s Paddock was closed this afternoon due to washout. Routeburn Road is being inspected after a report of a wash out there also.
The MetService issued a severe weather warning earlier today, forecasting heavy rain for Otago, Fiordland, Southland and Westland, and northwest gales for other parts of the South Island.
The active front is moving over the South Island today with a very strong and moist northwesterly flow ahead of the front bringing the heavy rain.
Tomorrow is forecast for morning rains, clearing later, with fine weather on Friday.
“What would be a concern was a significant rain event which lasts two to three days,” Miller says.
“But MetService long term shows there’s this heavy rain event, and then some rain but not anything of real significance.
“And after a few days the lake starts to drain out.”
QLDC and ORC began its annual flood awareness campaign with walkabouts in November. It maintains a database of cell phone numbers for retailers in case of flooding.
Major floods in 1995 and 1999 caused significant damage to CBD businesses.
Sandbagging and other flood prevention measures are introduced on a case by case basis, Miller says.
“But we’re not even close to that level of response yet.”