First stage of flood study begins

The first stage of the project, currently under way, is the investigation period where the team is gathering information.

Through the drop-in sessions, locals have been asked to provide images, maps, stories, flood line measurements, and knowledge from previous floods, specifically the 2011, 2022, and 2024 events.

North Central Catchment Management Authority manager floodplain Camille White was impressed by the knowledge that has been provided through the sessions, which will help shape their next steps.

“They’ve been so generous with the information they’ve shared,” she said.

“They’ve provided photos — someone had really good aerial photos — that information is critical to making sure we get some good flood modelling out of this.

“It all helps to make sure we’ve got the most accurate flood model we can get.”

Project manager John McCartney echoed Ms White’s sentiments.

“It’s been quite incredible, the information that’s coming out,” he said.

“Photographs of where the water was, seeing the water marks.

“Just the knowledge of where water went, the flood routes it followed ... I thought I knew a little bit about it.”

The team has also sought community suggestions on flood mitigation and emergency responses.

“We’ve also been asking the community ideas about future mitigation options,” Ms White said.

“We’ve had some really different ideas that I hadn’t thought of.

“Other things that we’ve been asking about is how we can improve flood warnings and flood messaging, really tapping into ‘what do they trust as their sources? What do they use?’.”

The second stage involves developing flood mapping technology, creating simulated flood events for community feedback, a process expected to take around eight months.

Residents will have an opportunity to comment on specific parts of the model through the software used.

“Our consultants use (the data collected) to run through and develop the flood model,” Ms White said.

“Then we’ll be coming out to the community again and basically check if they’ve got the modelling right from past events.”

Once the technology is finalised, it will be used to develop flood mitigation methods based on predicted water flow during future events.

“We get into what I call the exciting stage,” Ms White said.

“We can actually start looking at mitigation options to potentially reduce the risk.

“No options are off the table and nothing’s being dismissed.

“(Residents) have been really forthcoming and have had some really good ideas.”

Mr McCartney has been working with Campaspe Shire Council on flood mitigation in the region for many years, having the role of project manager for the 2018 Rochester Mitigation Study and in the 2023 Echuca Moama Flood Study.

“The previous study only went up to a certain level of flood, 2022 was much bigger than that,” he said.

“I think that’s why people were caught out because we didn’t have the knowledge of what happens beyond about a one-in-200-year, and it was bigger than that.”

There are three committees contributing to the study: the governance group made up of chief executives from local organisations, the project control group including consultants like Mr McCartney and Ms White, and a community reference committee.

The Flood Study Reference Committee is made up of community members representing a range of stakeholders.

Members are from the Rochester urban, rural and business communities, residents and property owners on the flood plain between Lake Eppalock and upstream from Echuca, as well as people with interest in Lake Eppalock and Campaspe River’s water resources.

“The community reference group is the really interesting one,” Ms White said.

“We put out expressions of interest for people to be involved.

“The role of that group is really (to be) a touchpoint for us.

“We have a community engagement plan, so they’re looking at, ‘are we engaging with the community in the right way?’.

“They’re not necessarily a decision-making group, but they certainly are about overseeing the project to see that it’s being delivered in a way so that the community is getting the outcomes they want.”

The team welcomes further information from the community including photos, data, measurements and stories, with submissions to be shared through a form on the Campaspe Shire Council website.

“If people feel like they have extra information, we’re still calling out,” Ms White said.

“Flood photos, especially aerial photography, any of that information is going to be super helpful.

“Rainfall figures of past events (is) really helpful information.

“It’s never unwelcome.”

Residents can also subscribe to the Rochester Flood Study webpage to receive updates on the project.