The part of Anzac Parade significantly flooded in June 2015 will be the first focus for Horizons Regional Council's flood resilience strategy.
The strategy will target the area where the flood led to resident displacement as well as damage to infrastructure and around 100 houses.
Horizons river management group manager Ramon Strong said it was time to make progress in adapting to an increased frequency of large floods as a result of climate change.
"We are starting with Anzac Parade as a significantly affected area, both because of the number of homes at risk and also as it's an important part of Whanganui," he said.
"It is lined with beautiful trees and is home to Kōwhai Park, a much-loved feature of the place."
Horizons has had previous conversations with the wider community regarding a broad approach to risk management for all parts of the city exposed to river flooding.
"It is critical we connect directly with homeowners and residents to understand their views and needs. We have to work in bite-sized chunks and so we will be engaging in other flood-prone, valued parts of Whanganui like Putiki and Taupo Quay later and look forward to inviting input to these projects when they commence."
The project will be led by Massey University's Professor Bruce Glavovic and Dr Martín García Cartagena, who are experts in natural hazards planning, flood risk reduction and community resilience building.
Strong said the appointment of these specialists was a good way of independently capturing resident, homeowner and community hopes and concerns about reducing flood risk and building resilience for the future.
He said Whanganui iwi and Whanganui District Council were partners in this process.
Between July and December 2020 there will be face-to-face interviews undertaken and opportunities for people to have their say in the formulation of the strategy.
"Residents and landowners along low-lying areas of Anzac Parade will be receiving letters in the next week or so inviting them to be part of the process," he said.
Whanganui mayor Hamish McDouall said he hoped the majority of Anzac Parade residents and landowners took the opportunity to take part in the project.
"This project will inform and influence the future of this area so I hope people are able to make time to share their views. Local experience and insight are vital," he said.