A dam wall on Cubbie Station at Dirranbandi has collapsed, flooding paddocks and swamping hundreds of modules of picked cotton.
An aerial photo posted on Twitter on Monday night, which has since been taken down, appeared to show a sea of water, dotted with swamped yellow cotton modules.
The breach followed storm rain in the district at the weekend.
It is unclear if surrounding properties have been affected, with many carrying livestock and producing crops.
Macquarie Asset Management, whose fund owns Cubbie Ag, declined to comment on the incident, as has Balonne Shire Council.
Across the district, contacted farmers are not speaking at this stage.
Cubbie Station is the biggest of Cubbie Ag's three properties, comprising more than 80,000 hectares developed for irrigated production as well as irrigation support infrastructure, areas for dryland cropping, and areas for grazing purposes.
The smaller two, The Anchorage and Aspen, are near St George.
The station's enormous water storages stretch for almost 30km of the Culgoa River at the top of the Murray-Darling catchment, with Cubbie Ag's total irrigation entitlements approaching 500,000 megalitres - enough to fill Sydney Harbour.
The company says the property has been designed to harvest water from significant flood events and store irrigation water on-farm in "extremely efficient" water storage infrastructure.
It says the gravity diversion infrastructure "proves highly beneficial both environmentally and economically".
More than half the farm is susceptible to inundation in a one-in-10-year flood, while many smaller floods would inundate little more than the floodways that have been left between farming land.
Cubbie Ag says the property's irrigation infrastructure is protected by levees, and "all levees at Cubbie Station have been assessed and comply with the Lower Balonne Floodplain Management Plan", developed by the Lower Balonne Advisory Committee.
The committee, formed in the early 1990s, represents stakeholders, including graziers and irrigators on the floodplain with a goal to develop a plan that would assess development proposals under a voluntary code of best practice methodology.
In February, an agricultural fund managed by Macquarie took 100pc ownership of Cubbie, buying Chinese-led textile giant Shandong Ruyi's stake (51pc) in Cubbie Station, associated properties and cotton ginnery.
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