The Hutt Valley is the most densely populated flood plain in New Zealand and, had Cyclone Gabrielle reached it, much of it would have been underwater.
Now, construction is about to start on raising the Hutt River's stop banks to ensure they can withstand extreme rainfall events.
"The area we are standing in is the weakest leak in flood protection in the Hutt Valley," said Daran Ponter, chair of Greater Wellington Regional Council.
Te Awa Kairangi runs adjacent to Hutt City which sits along a flat plain, making it extremely vulnerable to flooding - such as back in 2016 when communities were evacuated as the river burst its banks.
"If a bad flood comes along, Lower Hutt CBD would be completely flooded, causing billions of dollars in damage and untold lives could be lost as well," said Chris Bishop, Hutt South MP.
The Hutt Valley narrowly avoided being slammed by Cyclone Gabrielle last year, which would've led to devastation similar to Hawke's Bay.
"This area is only [providing protection] for a 1-in-65-year event, so had Cyclone Gabrielle come through this part of the country, the valley would have been inundated," Ponter said.
"We would have had serious flooding here in Lower Hutt. It would've breached the stop banks making it devastating for our local communities," said Campbell Barry, Mayor of Lower Hutt.
That's why the local councils are bolstering the city's flood protection measures.
"We know with our changing climate they are going to become more regular, so we need to get on with these projects and that's what today's about," Barry said.
"The flood bank work will upgrade it to 1-in-440 years. That is a huge difference," Bishop told Newshub.
It's anticipated it will take about four years to fully complete, expected to protect about 3000 homes.
"It will help us sleep a little bit easier at night when we see those weather warnings," Barry said.
Construction will begin at the end of the month.
