Smoky bandit said:
Well when you put it like that you can see why they may want to regulate large agricultural farms and their water use..
But for the average joe blow like me it's only used for washing machinery and watering a very small amount of livestock..It has saved me alot of money over the years especially when theres been no rain for long periods.
It is all relative. On the scoria cones around here, average Joe Blows come to blows over other Joe Bloes destroying their flow from further up-slope. There are so many variables - big company cropping, family sheep farming on a hundred thousand hectares, growing berries on scoria cones and potatoes downslope. It was not a value judgement, it was an explanation of why it is done that many people are unaware of. Obviously the average small farm bore is not the main concern, but there is an attempt to get as complete a database as possible - bores are one of the best "samples" that scientists can have to understand flow that they cannot see - there are other methods, electrical etc, which help fill in the flow between such bores.
Probably another thing that most people don't realise is that surface water and groundwater are continuous - pump too much water from bores and the rivers stop flowing. For a long time the government pushed the idea that Murray Basin salinity was caused by deforestation of the highlands - now known to be nonsense (the water in aquifers around Ouyen for example has taken 15,000 years to get there from the highlands and forestry was not an important industry in those days). It is an issue however on controlling salinity on the scale of your farm or along the side of a range of hills. The primary cause in areas like the Murray Basin is underground water at less than 30 m depth that has a salinity seven times that of sea water - in the 1970s we had very high rainfall that raised the water table by up to seven metres and it is only still slowly dropping - the salt from the water below was brought up into the grass roots as a result - flattish pans that used to give good wheat yields are now salt pans......this also impacts on the Murray, the sudden increase in its salinity near Red Cliffs is related to discharge of saline water from this aquifer at that point. We have modified drainage around Lake Corangamite in wet-as-buggery southern Victoria near Colac, and discharge there has caused it to have water much saltier than sea water (they also used to have a bit of a nitrate problem) - we can even see that from satellites.
The government is not only interested in the flow (and your consumption) from bores, but monitors variations in things like salinity, nitrates (eg from your pea crop), sulphates over time, to get advance warning of upcoming deterioration in the aquifer.