Future, Cay, the main issue with irrigation water is that it is grossly under-priced, encouraging excessive and inefficient use. Users of course recognised this, and the value of water rights has become built into property prices, making it difficult to unwind. Although the COAG water reform agreement about a decade ago provided that all new water supply should be priced at the full cost of provision (which is dominated by the capital cost) and that pricing for "old" water should be more cost-reflective, there has been only lip-service to this in Queensland and probably elsewhere. Assessments of the viability of the Paradise Dam, for example, were based on user surveys indicating supply at existing prices, which I calculated were on average in Queensland 23% of the cost of supply - not even enough to cover marginal costs and maintenance. (Even then, there was no prospect of the dam being viable.) Earlier discussions on the Dawson Dam were based on prices which were viable for farmers, but far below the expected cost of supply. Environmental degradation will continue so long as under-pricing continues.

“Graziers like water, and the cheaper it is, the better. Environmentalists thrive on crises - no environmental problems, no crusades.”

What a terrible way to start. No pretences of being unbiased, just straight into knocking the stuffing out of environmentalists. Wonderful.

Surely a comparable statement to “Graziers like water, and the cheaper it is, the better” would have been something like; ‘Environmentalist like a healthy environment that gets the water it needs to remain healthy’.

Needless to say, most environmentalists loathe being involved in any sort of confrontation or hassle. So mush so, that only a very small portion of people who share concerns about any particular environmental issue actually become involved in it in any significant manner.

“Their photographs suggest the cattle would be having a significant impact on ground flora and fauna and water quality. But the data necessary to understand this impact is not being collected.”

Well at least there is a passing though here, but nothing more.

There is merit in environmentalists forming an alliance with graziers if it means more water for the environment. But intensive grazing has its own set of very significant ecologically degrading factors. It is certainly a crying shame that these factors don’t appear to be monitored on private land, or even in the reserves apparently.

While large and diverse bird populations can coexist with cattle, grazing changes the balance between different grass and herbaceous species with the elimination of some, leads to the thickening up of woody species in conjunction with reduced fire, and often facilitates the introduction of weeds. Related faunal changes are often very significant.

So it is a real trade-off for environmentalists to secure half-decent water supplies for environmental reasons, if it means that the same water is being used for grazing or agricultural purposes.

Jennifer,
How do references to bird breeding events post 1986, without an indication of the volume of water in each of the 1990, 1998 and 2000 events or of the antecedent conditions in the Marshes before receiving the floods in those years; make my statement relating to pre Burrendong Dam conditions ridiculous?
Future

Future,
You made the statement that:
"Prior to the construction of Burrendong Dam millions of birds bred every year."
This suggests that prior to the construction of the dam, inland Australia was not a land of drought and floods? That there was always water?
It is my understanding that waterbirds 'disappeared' during dry times, and there were plenty of those before the dam was built. I understand there were about 15 major flood events in the 50 years between 1900 and 1950.

Future you have made two major errors. Firstly your assumption that millions of birds bred in the Macquarie Marshes every year before the Burrendong Dam was built is quite wrong. The period 1900 to 1949 was quite dry with some long drought periods, and records are clear that when the Marshes were dry the waterbirds went elsewhere.
Secondly your assumption that water that flows into the dam is water that should be flowing into the Marshes is also wrong. Under natural conditions the Marshes got about one third of the flow in the river. The other two thirds went to a variety of distributary creeks and small wetlands, and the river channel itself which is hundreds of kilometers long.
Ludwig asks how can we get the best outcome for the environment here? As Jennifer points out grazing and levees and channels built in the Marshes are having a much greater impact on it than its water allocation.

Brolga,
Those distributary creeks and smaller wetlands were originally all part of the Macquarie wetlands system and birds bred in all those places.
50% of Australia's wetland systems have now been destroyed. There are very few 'other' places for water birds to go to.
According to Department of Natural Resources - the years 2001 to 2004 have been the driest 3-year period on record for Marshes inflows while 2002/03 was the driest 12-month period on record for the Marsh inflows.
Although there have been lots of dry times that are natural to the Australian climate, it is my understanding that a core area of the Marshes remained wet because it naturally received a variety of low, medium and high flow events in the system.
Future