Residents had to be evacuated from flooded properties on Anzac Pde. Photo / File
Residents had to be evacuated from flooded properties on Anzac Pde. Photo / File
As we enter a new decade, we take a look back at some of the biggest stories that hit the headlines in Whanganui over the past 10 years.
Whanganui's biggest natural disaster of the decade in June 2015 resulted in flooding destroying properties and infrastructure, and causing heartbreak for many.
After a wet April and May, the region's soils were already saturated when rain fell steadily across two days on June 19 and 20.
The rain began slowly but from 8pm on Friday, June 19, it was relentless. For the 26 hours until almost midnight on Sunday, about 100 millimetres of rain was dumped on Whanganui and the surrounding district - about 130 millimetres in a 36-hour period.
Low-lying properties, such as around Putiki, flooded first and people were evacuated from there. Then streams overflowed and hill country began slipping under the weight of water.
The Whanganui River peaked at Pipiriki at 15.7m at 9pm. Close to midnight its banks burst, failing to hold the 190 million cubic metres of water it had to deal with.
By Sunday morning the city was bathing in a warm winter sunshine but residents were waking to the damage. Flood waters had destroyed houses on the east of the river and inundated Taupo Quay with water and silt creeping up Victoria Ave.
The repair bill for the Whanganui River Rd ran into the millions. Photo / File
The extent of flooding came as a surprise to authorities, largely due to the amount of rain between monitoring gauges in town and up the river at Pipiriki. The amount of localised rain threw out flood prediction models because there was much more water moving a lot faster.
It wasn't until later on Saturday afternoon and early evening that an emergency meeting was held and it was decided people needed to evacuate from Anzac Pde. More than 100 households, and 200 people, were evacuated on the Saturday evening, with little notice and in the dark. The river topped the stop banks on Anzac Pde just before midnight, a few hours earlier than predicted. A state of emergency was declared, cordons were put up around the flooding and all bridges over the Whanganui River were closed.
State Highway 3 - north and south of the city - and State Highway 4 were closed, meaning the city was isolated until late on Sunday. Whanganui's neighbours, South Taranaki and Rangitīkei, were also affected by flooding, with more than 30 houses in Marton evacuated and the river settlements of Waitotara and Whangaehu inundated with water and rural roads badly damaged. There were thousands of slips across the district.
The community rallied to help those affected by the flood, the Red Cross set up an appeal fund, Whanganui mayor Annette Main established a mayoral relief fund and the Manawatu Whanganui Regional Disaster Fund was activated. A number of organisations collected food and teams of volunteers helped with the clean-up.
About half a metre of silt had to be removed from Kowhai Park after the flood water had cleared. Photo / File
A year on people remained out of their homes and roads and bridges were still in need of repair. In June 2016 the Whanganui District Council introduced a storm damage rate to help pay for repairs to its infrastructure.
In 2019, two years after starting the work, the NZ Transport Agency finally finished repairs to the pathway on Anzac Pde near the Whanganui City Bridge, an area badly damaged by the flood, but other slip repair work is yet to be completed.
The June 2015 flood was originally assessed as a one-in-85-year flood but that was quickly upgraded to a one-in-100-year event. However, it was later deemed to be a once-in-130-year event, with a 0.77 per cent chance of happening in any given year. The likelihood of that amount of rain falling in coastal Whanganui in 48 hours is one in 100, or a 1 per cent likelihood in any year.
Peak flow at the City Bridge was 5150cu m of water per second (cumecs), making it the second biggest flood recorded in the North Island, behind the Mohaka River in 1938.
