Top of the catchment graziers recall two metres of rain the week before massive landslide as survivors reflect on a year following the big flood

At Tim and Anna Gilliland's property 1398mm fell the week prior before an astounding NSW record of 698mm in 12 hours which triggered a 12 hectare landslide that started in Mount Jerusalem National Park and spilled out onto their grazing flats.

"I said to Anna, I don't know which way to run," recalled Tim Gilliland, when they woke in the dark at 4:30am to the sound of snapping tree trunks and growling boulders they later confirmed were the size of buses.

The torrent of water from the sky fell away down the creek to menace Murwillumbah on the Tweed while just over their back boundary, the rain fell into Cooper Creek catchment which flows into the Wilsons River which drowned Lismore ... and on it went.

A rare fire in the National Park rainforest above their property during 2019 burned out tree stumps and roots, allowing rain to penetrate into subsoil. The land was like a colander.

"I can guarantee you 100 per cent that this would not have happened without that fire coming first," said Mr Gilliland.

With fences down and a new braided stream bed covering their flats the family scrambled to contain cattle and sift through the machinery shed. A mate with a D6 bulldozer was hired to push boulders out of the way and Mr Gilliland buried them with his excavator.

"Our flats are all red soil but the rock that came down was volcanic ash-stone," he said.

A second flood a fortnight later dumped about 300mm overnight, but the exact amount remains unknown as the rain gauges were broken.

"If anything that one did us a favour" said Mr Gilliland. "It showed us that Doon Doon creek wanted to go down its new course and no matter how much we tried to put it back we just had to go with it."

The rain washed the paddocks to a degree and deposited lighter silt that was easier to manage.

The dozer was in the paddocks until one month ago, with a flood grant covering its costs plus some of the fencing but there remains a long way to go.

The bulk of the clean-up project took six months and left the family exhausted but triumphant.

"The council was brilliant, the SES excellent," recalled Mrs Gilliland. "We have great neighbours. It really brought the community together. The experience was more uplifting than anything else. I actually feel a lot better for going through it. The farm was just getting to where we wanted but we will build back better."

Australia's leading scientific body, the CSIRO, has tapped into Lismore's community concerns about flood mitigation projects to come up with a list of short term priorities.

This report will form the basis of how initial funding of $50 million, out of a total pool of $150 million, will be spent across the North Coast region to implement shovel-ready projects.

Big tickets items for Lismore includes $22.5 million allocated to upgrade pump infrastructure including $2.6 million to install an electric pump station to replace the tractor-driven pump at one point along the levee wall.

The CSIRO will deliver a more comprehensive report late next year, and Federal Emergency Services Minister, Senator Murray Watt said this could include big infrastructure projects, like retention dams and levee walls.

Asked if these mitigation measures would stop a flood like February 2022, Mr Watt said: "I don't think you can guarantee that communities that live in areas that do flood will be entirely safe from every single possible flood."

- Cathy Adams

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