Tuesday, October 12, 2010

Murray /Darlings True Enviroment defies the experts.

I once referred to the Murray/Darling system prior;to recent human interventions  as Australia's biggest STORM WATER DRAIN .As such it flooded to the ocean shifting its estuaries and discharge position by Kilometers depending on how long it was between heavy rainfall events. In between  it dried into often salty pools or long sandy stretches.At the time of European discovery its temporary estuary was that stretch of water named Lakes Alexandrina or Albert  and as Sturt discovered, that estuary was fast filling with sand and the river contemplating a new discharge point when a suitable flood eventuated.

In flood times the River Gums and other flora got a drink and the associated fauna took advantage of that.So intermittent was this event that even the Marsupials evolved to a situation of delayed pregnancy carrying partly developed foetus for very extended periods until food arrived.The Aboriginal population was also sparse and itinerant.

The Berri hotel features a photograph of the 1914 local Primary School picnic IN THE RIVER BED with only a small puddle in sight.Sturt's first encounter with the Darling was one of a chain of extremely saline pools .

This is the true environmental picture of the Murray- flood or dry. The Adelaide region that we know today grew no lawns, gardens or enjoyed  reticulated water supply and sewerage. Its residents had no quarrels with its nor eastern neighbors if the water flow did not reach their territory nor did they complain nor seek compensation in beads or trinkets if those whose territories being subject to excessive rainfall sent them a flood.If the flood produced excessive vegetation they set it on fire before in could become destructive thus ensuring also the longevity of the established trees from over population and the destructive wild fires which nature used  otherwise to correct such neglect.

The intervention of European settlement changed all that by installing dams and weirs and then the ultimate insult to the Rivers independence. The South Australian Barrage system .Worse they produced politicians whose views of the  ENVIRONMENT had nothing whatsoever to do with mmaintaining a river system based on historic evidence but everything to do with the demands of their voting consumers and more particularly in latter years a prosperous self serving educated elite financially independent of the reformed river system who use that status to defy the evidence of history in pursuit of community funded research grants based on altering an environmental situation of its own making.

So before some one gets the impression I am about to advocate the complete closure of the irrigation industry let me say I support it completely I am just browned off with those who defy the environmental history in the name of the environment.For instance considering the rivers stop go practices of the past what benefit is now achieved by allocating stored water to " ENVIRONMENTAL FLOW" other than of course to ensure the citizens of Adelaide get a ration of water that did not precipitate in that territory nor was it regularly available to evaporate in Lake Albert or Lake Alexandrina.Now that the taxpayers have funded a water conservation infrastructure why let a drop of that water flow to the sea or support a primarily recreational economic activity equally comfortable with sea water as evidenced in WA by the Dawsville Cut which allowed the sea into the Southern Estuary of WAs Murray River near Mandurah Thus delivering recreational,economic and significant environmental correction of a man made problem

WE have changed the environmental structures of the Murray / Darling and no one is going to remove the offending infrastructure from which we all benefit and if sufficient water is in the system why not grow things we can eat or clothe ourselves as compared to red gums whom the environmental lobby and the politicians who value their voting preferences have denied us the right to harvest for sustainable use instead of  allowing nature to burn them down periodically.

.The available water is then not over allocated to irrigation its rate of consumption can be controlled periodically  to respond to inflow and available storage If you want to water the flood plains to the historical average then achieve this by infrastructure such as temporarily raising some Weirs or pumping .Costly but cheap compared to the economic mayhem proposed by the current cutbacks to entitlements and certainly more environmentally effective than flowing that water down to the lawns of Adelaide or to evaporate in the Murray estuary so as to support recreational boating and fishing quite adaptable to salt water .

Let me also put the case for annual crops like Rice and animal grazing which can much more easily respond to the historic vagaries of river flow and therefore provide the balance with perennials for which reserves must be maintained.

To summarise   Directing stored water to flow to the sea is counterproductive both environmentally and economically.Such an initiative does not engender the intermittent flooding inherent in the environmental structure  of the river system and who wants to return to floods and a dry river cycle anyway?

This initiative will not maintain a permanent opening to the sea and the politically motivated dredging should be abandoned and the funding allocated to a permanent channel to connect the Coorong to the sea.

Finally those who prosecute their case on the emotive dogma of " ENVIRONMENTAL FLOW "should provide the empirical evidence of the achievement of a return of the historic environment of the River that this will achieve or is it a fact that the economic destruction of the irrigation industry by a thousand cuts is necessary to return the river to its past?

An additional Weir at or near Wellington is probably also a good idea


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