State Government water authorities have for eight years fabricated data they claimed was being collected at a river monitoring station that does not exist.
The revelation indicates the Government might be failing to deliver on commitments to release enough water to keep drought-stricken rivers flowing.
Water authorities are bound under the Water Act of 1989 to maintain river flow gauging stations at designated points.
But Government assurances have been undermined with an admission by Southern Rural Water it has been "calculating" river flow readings from a phantom gauging station near Sale.
West Gippsland Catchment Management Authority and Southern Rural Water have invented the readings taken at the last gauging station on the Thomson and Latrobe river system before it flows into the Gippsland lakes.
Gauging station number 226027 at Swing Bridge, five kilometres south of Sale, does not exist, despite $70,000 being set aside for its installation in 2000. Until last week, the authority was insisting the station was working to record the level of freshwater flowing to Lake Wellington in the internationally recognised Gippsland lakes and wetlands.
"There is monitoring there, it has been there a long time," said Southern Rural Water spokesman Craig Parker.
"It is a site that has historically been used as a compliance point but you might take up with the Department of Sustainability and Environment whether it will continue into the future. It is a partnership site where a number of agencies … co-ordinate the management. West Gippsland Catchment Management Authority employ a person (to take readings).
"I am as certain as I can be," Mr Parker said before later confirming the gauging station had never been installed.
The Sale Swing Bridge, built in 1883, spans the Latrobe River at its junction with the Thomson River. The Victorian Water Act 1989 requires authorities to collect data to ensure the passing flows meet bulk-water entitlements allocated for the environment.
Freshwater levels at Swing Bridge have been calculated based on readings taken kilometres upstream at the Kilmany South and Bundalaguah, minus entitlements for irrigation and industry.
Southern Rural Water later told The Sunday Age one of the reasons the Swing Bridge monitoring station had never been installed was that it was impossible to split fresh water from the salt water wedge of tidal flows that run beneath.
But former general manager of Lake Wellington Rivers Authority, Ross Scott, said the technology had been available for a decade.
"They just don't want that site," said Mr Scott. "Forty per cent of the time they are not meeting the flows guaranteed under the bulk entitlements at the gauging stations further upstream at Kilmany on the Latrobe and Bundalaguah on the Thomson and there are absolutely no controls on extractions, legal or illegal, between those stations and Swing Bridge."
Conservationists and environmental groups have long accused the Government and water authorities of failing to properly monitor and control the quantity and quality of water reaching the Gippsland lakes and wetlands.
Last year chairman of the Gippsland Lakes Taskforce Professor Barry Hart admitted at a public meeting that the authority had failed to adequately monitor the vulnerable wetlands' health.
Southern Rural Water insists it is properly monitoring levels by calculation, observation, metering and a system of local landowners dobbing in suspected water thieves.
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