Hi Kiwipaul
In NSW a bit different in that the Owners Corporation receives one bill for the total water consumption, and individual owners are hit separately with a bill for a supply or connection charge. As Jimmy pointed out, the Owners Corporation expense is included in the levy notices by apportionment according to Unit entitlement. In NSW each unit owner could only be charged the same amount per unit if each unit had the same entitlement.
There are pluses and minuses to having individual meters to each unit. There is the cost of metering, and the need to read the meters on an ongoing basis, and the extra accounting involved. Then there is the question of unmetered supply to common areas, in our case with fairly extensive common grounds we would find residents less willing to water lawn areas if they were to be also footing the bill through their meters. And then if owners dispute their bills how to test and identify faulty meters.