Years of erosion mitigation washed away

Kenilworth landholder Kathryn Clarke-Bevan said metres of fencing and thousands of newly planted trees that were part re-vegetation efforts, were completely washed away following a rain event, that left a seven to eight metre 'sheer cliff face' where the river bank edge had previously been.

She and her family moved to the area from Chinchilla in 2016, after purchasing a century year old dairy where they now run a cattle stud, Glenroy Speckle Park.

Their 80 acre property incorporates a stretch that runs along the the Mary River.

Government funded pile fields were installed on their property in 2019 to mitigate erosion on the river bank.

"We are virtually on a 90 degree angle, and there was a lot of erosion," she said.

"In the last weather event, because it rained over such a long period of time, the land became waterlogged and washed some of that re-vegetation away.

"We are in the process of getting the MRCCC to come out and see what more we can do."

She said they get support if there is funding available but do in-kind maintenance, including fencing and planting trees.

"There have been about 40,000 trees planted but we would have lost a couple of thousand with the most recent weather event," she said.

"Calistemons have long deep roots and we hoped that would be enough, but it gets so waterlogged because of the sand, the land slumps and gets washed away.

"It is quite gut wrenching when you put so much time and effort into it and ecosystems start to come back."

In order to preserve the river bank the family fenced 25 metres back from the waters edge, which prevented the cattle form accessing the land.

"We put troughs in so the cattle can still remain on that site because it is better country down there," she said.

"I went to move the cows after the last weather event and the whole bank, fence and all, was gone. It's just a sheer cliff now."

She said they are waiting for the report from the MRCCC, to see if they might be able to put stronger measures in place as there was little point in re-vegetating again.

"It honestly comes down to funding, so we will have to see what is available," she said.

"I'll just have to wait in line. I am sure there are people in the same position...I know they have two large projects they are looking at, so it depends on when funding comes through.

"It held out for a few years but at the end of the day mother nature will do her thing."

The Mary River empties into the Great Sandy Strait at Rivers Head, south of Hervey Bay.

The 2050 Water Quality Improvement Plan identified the Mary catchment in the top five contributors of pollution in in the Great Barrier Reef.

A four-year Mary River Recovery Project between Burnett Mary Regional Group and MRCCC was implemented to prevent thousands of tonnes of sediment flowing into the Great Barrier Reef.

The project had been underway since July 2020 and is now two and a half months from completion.

MRCCC operations manager Brad Wedlock said they had achieved the goal of the project, which was to reduce 26,000 tonnes of end-of-catchment pollutant from entering the Mary catchment, but there was still a lot more work to be done.

"Eleven sites were chosen for remediation in the four year period up stream in the Kenilworth reach and down stream around Tiaro, north of Gympie," he said.

"Back in 2019 we used LiDAR (light detection and ranging) and looked at the sites experiencing the most erosion along the Mary River.

"This was from a period from 2009 to 2018, so the data had the 2011 floods and we could see how fast these things were moving and the quantity of sediment."

Mr Wedlock said in the Kenilworth reach all the sites they'd remediated went through the 2022 floods, had trapped sediment and hadn't eroded but now they were observing two to three metre high pressures along the river due to consistent bouts of rain.

"It's creating problems in places where we haven't done stabilisation work," he said.

The consistent rain meant the Mary River level hadn't dropped since January, and the MRCCC hadn't had a chance to collect data from the most recent erosion sites.

Mr Wedlcock said the MRCCC are in the co-design phase of a seven year project, with the federal government, through the reef just program, which will incorporate landholders who have had recent erosion on their properties in the Kenilworth reach.

"The first phase is due at the end of this month or early May, so we have been working with the federal government and different parties in these catchments, putting together a proposal for the next seven years," he said.

"We have acknowledged the problems that we have got in the Kenilworth reach, we just don't have any recent data...we can't go back to LiDAR and validate how much loss there has been.

"So we are writing it into the narrative that we have to investigate certain sites in the reach that continue to lose land and are on a trajectory now.

"The seven year project is scheduled to start in the new financial year."