The devices, designed to prevent contamination of the town’s water supply, can cost up to $1500.

Then there’s a $75 council registration fee and $180 annual audit charge.

Critics of the policy say Council is throwing a blanket over the issue, rather than assessing individual risk.

One local, Gos Cory, is calling for more accountability and explanation.

“The major logical flaw in the regulations is there is no significance attached to the relationship between the two supplies,” he said.

“You really have to use your imagination to envisage how a bore used for irrigation could become connected to a town supply, overcome the existing back flow protection and overpower the inherent pressure of the town supply.”

The devices cost anywhere from $500 to $1500.

The Goulburn Post is aware of another local concerned about the price and Council’s ‘generalist’ policy.

Both men say it’s an impost on property owners without proper justification.

The council has been auditing bores and grey water systems in Goulburn and Marulan over the past three years.

The purpose was to inform owners of their responsibilities about water quality protection and backflow, water services manager Grant Moller previously said.

“Backflow is a condition where water can flow in the opposite direction from a property into Council’s town water supply,” he said.

“In order to prevent this contamination, backflow prevention devices must be installed for boundary containment on all water services connected to Council’s water supply systems.”

He maintained all properties connected to the town supplies had the potential to be a source of contamination should a backflow event occur.

Mr Cory and wife, Liz, installed a bore at their Clyde St property shortly after purchase. It was during the drought in 1999 and the town supply could not support irrigation of the extensive grounds. The separate system, with its own network of pipes, also reduced the expense of watering.

In addition, the couple has two onsite 25,000 litre tanks holding water from downpipes, driveway and roof runoff.

The bore can pump out 2500 litres per hour but is not in any way connected to the domestic supply, Mr Cory says.

He told the Post that by insisting on backflow devices, Council was applying the highest level of risk, that is the threat of human death, rather than assessing it realistically.

“There are far greater risks around that they are not mentioning,” Mr Cory said.

He cited rainwater tanks, subject to bird and animal droppings and lead roofing, pumps from dams or waterways, on-site septic systems with transfer pumps and swimming pools with automatic top up devices from the town supply.

He argued that if Council seriously thought there was a contamination risk from bore water used on his property, then it should identify the source. As it was, there was “no real attempt” to investigate how a bore being used solely for irrigation could become connected to the city’s supply.

Mr Cory has pursued the matter with senior Council staff without success. He has been unable to glean details of when the policy was placed on public exhibition, whether any submissions were received and whether in making the decision, councillors were told of the financial impact on ratepayers.

In the latest correspondence Council advised that if he didn’t install the device by November 3 he risked being disconnected from the town supply.

“If Council is prepared to do an individual assessment and vary its policy, then I think that would be a reasonable outcome,” Mr Cory said.