Ballina would be the big “winner” if flood mitigation measures proposed by the CSIRO in its final report into flooding in the Northern Rivers were implemented.

That’s what a packed public meeting at the Ballina Lighthouse & Lismore Surf Life Saving Club was told on Wednesday.

CSIRO hydrologist Dr Jai Vaze said modelling showed the upstream works would dramatically reduce flood impacts in Ballina.

“None of the actual changes are implemented in Ballina,” Dr Vaze explained.

“But because we can hold back that water, we reduce the level in the stream in Ballina, by about 0.72m, that is enough to save half of those houses and businesses from flooding.

“If a house had one metre of flooding in 2022, with these measures in place it would be dry.”

The proposed mitigation works are the culmination of several years of work by Australia’s national science agency, which examined a range of engineering options aimed at reducing flood levels across the Richmond River catchment.

The proposed package of works includes building detention basins across the Richmond River catchment, a Tuckean Swamp bypass and drainage works, an upgrade of the Baggotville barrage and a one-way pressure gate at Boundary Creek.

The gate would allow floodwater to escape while preventing tidal seawater from entering the system.

“When Baggotville barrage is operating like it is designed to, it will drain the water faster from the Tuckean Swamp,” Dr Vaze said.

“Another thing helping Ballina is the opening of Boundary Creek, it just makes the whole system much more efficient.”

Much of the discussion at Wednesday’s meeting focused on nature based solutions, where detention basins would be built and the impact on housing and the future impact of climate change on floods.

And that frustrated people like Empire Vale cane farmer Mick O’Connor.

 “I came to this meeting thinking it was a Ballina meeting and we we were going to be discussing things about Ballina,” he said.

“Lismore, Kyogle, Casino and Woodburn all got their meetings, but there was very little discussed about Ballina here.

“It is very easy to stack a meeting if you have got a particular view, you can get a busload of people and turn up at every meeting.”

He was generally supportive of the proposed CSIRO flood mitigation measures.

“I think the work they have done is probably the first independent scientific report we have seen,” he said.

“To me there are a few simple solutions. The Tuckombil canal is an easy fix. A spillway at Boudnary Creek or Salty Lagoon is another one that will help take a fair amount of pressure from Ballina and would help famers as well.”

A further $3 million has been allocated now to undertake a detailed feasibility study across the Richmond River catchment before any final investment decisions are made.

Work on that is expected to get underway in August.

Photo: CSIRO hydrologist Dr Jai Vaze addresses a public meeting in Ballina on the agency’s proposed flood mitigation measures. Also pictured is Empire Vale cane farmer Mick O’Connor.