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  • Media Articles 2008 - Lakes Need Water
    2008 Interesting articles about the water issues of the River Murray and the Murray Darling Basin The opinions expressed herein represent those of the authors Murray water demands from downstream Jennifer Marohasy 4 September 2008 Plan to save lakes buy 6 farms The Age 8 August 2008 Why worry about Albert and Alexandrina The Age 8 August 2008 Too much water under the bridge The Australian 8 August 2008 Garrett

    Original URL path: http://www.lakesneedwater.org/media/media-articles-2008 (2016-02-09)
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  • Keeping Murray Mouth open - Lakes Need Water
    the prominence of this environmental outcome for the Murray mouth there is very little explanation or technical details in the report to justify the benefits and costs of this increase in flows through the mouth If the proposed plan was really serious about environmental outcomes in this area then it should have incorporated the recommendations of a major study by environmentalists for the Murray Darling Basin Commission in the year 2000 called River Murray Barrages Environmental Flows an Evaluation of Environmental Flow Needs in the Lower Lakes and Coorong This report does not recommend more freshwater flows but states that the main factor driving environmental degradation in the Lower Lakes and the Coorong has been the construction of the artificial barrages which have reduced the size of the River Murray estuary to 11 of its natural size They state The primary change for the Lower River Murray since the construction of the barrages and the dramatic reduction in flows has been the loss of the vast estuarine system and the consequent loss of biodiversity and ecological resistance The ecosystems are at risk of degrading into a uniform condition having low diversity and interfering with the natural productive capacity of the region particularly from a fishery perspective They state that the value of commercial fish in the remnant estuary is equal to the value from the whole of the freshwater lakes which is nine times as large They recommend moving the barrages up to the real mouth of the Murray near Wellington so as to instigate a tidal prism which would be nine times larger than the present prism and would help to keep the mouth to the sea open As an interim measure they recommended increasing the size of the estuary by cutting a channel from Lake Albert to the Coorong and subjecting this lake to tidal changes All of these actions would lead to a much greater improvement in the environment of the Lower Lakes and the Coorong than keeping the sea mouth of the Murray open for 90 of the time It would also save most of the senseless waste of 7 000 GL of fresh water into the sea an amount which is of the same order of magnitude as the 10 873 GL of sustainable diversions recommended in the proposed plan One of the spurious reasons given for these planned flows to the sea is that it will flush salt from the system Low river flows between 2007 and 2010 show up the lack of logic in this argument as salt levels at the Mannum takeoff for Adelaide water did not rise above tolerable levels when no water went over the barrages in 4 years The reason for this is that there have been 18 salt interception schemes constructed along the Murray in the last 40 years with a capacity for removing 1 500 tonnes of salt per day and this has led to a continual improvement in salt levels in the lower reaches of the

    Original URL path: http://www.lakesneedwater.org/letters/keeping-murray-mouth-open (2016-02-09)
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  • Water Wasted - Lakes Need Water
    water so that it is the ocean water that evaporates There are two engineering mistakes made on the Murray River The first was the construction of the barrages at the bottom of the Lower Lakes to provide fresh water to abutting farms and communities The recent drought exposed this mistake The State Government originally proposed the correct scientific solution ie open the barrages and build the Wellington Weir However the State Government gave into ill informed community pressure and perpetuated the mistake by insisting there was only a fresh water solution to the Acid Sulphate Soil that was exposed in the lakes This was an out and out fabrication to con money out of the Federal Government to fund white elephants ie Clayton Currency Creek and Finnis River regulators for 26 million The other Engineering mistake was the putting of the pumping station for the Adelaide water supply below Lock 1 This meant that if the Lower Lakes were returned to an estuary by opening the barrages the water supply would be vulnerable to salt water intrusion up the river The original plan to install the Wellington Weir was a move in the right direction except for the location which should be at Newport and simply high enough to stop a high tide intruding upstream Ironically the Government did one positive thing It delivered mains water supply to all farms towns and communities which had become reliant on the lower lakes being fresh Therefore there was no reason why the Lower Lakes could not be opened to the ocean The addition of the water from the Lower Lakes to that from the Coorong would mean that the volume that would pass through the mouth twice a day at the change in tides would be sufficient to keep the mouth open

    Original URL path: http://www.lakesneedwater.org/letters/water-wasted (2016-02-09)
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  • Lower Lakes and Sea Levels - Lakes Need Water
    region particularly from a fishery perspective SA Dept Water Resources for MDBC 2000 Barrage Gates Open January to May in 2011 Between January and May 2011 the majority of the gates of the Lower Lakes barrages were open to allow River Murray flood waters flow out to sea During this period flows over Lock 1 ranged from 50 GL d to 78 GL d in mid March before declining to 21 GL d at the end of May when the number of open gates was reduced from 402 to 47 then 25 to prevent further sea water intrusions The period whilst most of the gates were open was an ideal opportunity to observe the interaction between sea and river levels The results of recent water level observations from the Murray Mouth along the Goolwa Channel and into Lake Alexandrina are summarised in figure 1 below The readings were mainly taken from the automatic recorders installed during the drought Relationship between Lower Lake water levels tide and storm influences and seawater intrusion Figure 1 The plots A1 and A2 show River water levels from Murray Bridge to the Mouth at flows of 50 to 78 GL d over Lock 1 At lesser more normal flows the slope would be shallower and approaching mean sea level 0m AHD in the absence of the barrages Plot B shows that at normal maximum spring tides the flow of water was reversed and salinity recordings show sea water intrusion extended to just beyond the Hindmarsh Island Bridge Plot C occurred on May 22 when spring tides coincided with an intense low pressure system and storm winds to 40 knots This event caused saline intrusion up past Point Sturt and to Milang and Mulgundawa in Lake Alexandrina From May22 to July 31 there were 4 similar

    Original URL path: http://www.lakesneedwater.org/letters/lower-lakes-and-sea-levels (2016-02-09)
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  • Witholding the MDBA Report - Lakes Need Water
    Wentworth Group reports The Urgent Provision of Water to the Coorong and Lower Lakes Sept 2008 and Sustainable Diversion in the Murray Darling Basin June 2010 and seeing the current situation as of the 14th July 2010 where the total Basin s holding is 7550GL 33 3 you can see why the Murray Darling Basin Report hasn t been released Alan Holmes said on 891 ABC radio this morning 10

    Original URL path: http://www.lakesneedwater.org/letters/witholding-the-mdba-report (2016-02-09)
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  • Lake Alexandrina vs Goolwa Channel - Lakes Need Water
    could be accomplished by other means rather than deprive the Lake from much needed water Since the beginning of winter the water level in the Goolwa Channel has risen 0 3m to 0 2m AHD as a result of approx 180mm of local rainfall Now that the catchment is saturated there should be sufficient rainfall in the next 2 months average 90mm to raise water levels in the Channel above 0 3m AHD said to be by the proponent the minimum required height to allow the Barrage to be partially opened and achieve connectivity without deleterious effects If this is the case then all the objectives specified by the proponent will be met by local runoff only The salinity of water in the Goolwa Channel currently ranges from 18 000 to 21 000 EC units between Clayton and the Barrage to less than 5000 10km up the Finniss River Even if some limited mixing of sea and brackish Channel water were to occur in the vicinity of the Barrage there will still be more than sufficient diverse fresher water environments available further upstream Furthermore I consider that any decision to allocate water now that the MDBA report has been deferred

    Original URL path: http://www.lakesneedwater.org/letters/lake-alexandrina-vs-goolwa-channel (2016-02-09)
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  • Water levels below sealevel are unnatural - Lakes Need Water
    only natural state of this estuarine system they are apparently willing to accept these vast expanses of windblown sand the exposure of acid sulphate soils and the physical restructuring of historical shorelines as a preferred and more natural option than the creation of a living estuary To promote the vegetation of these exposed lake beds as a management solution when the strategy is clearly flawed and has demonstrably failed to remedy the problems of windblown erosion and deposition over large areas is a waste of public money and effort if a viable and much more environmentally friendly alternative is readily available To continue to refer to these projects as revegetation with all the reassuringly positive connotations that this term generates when used in the context of restoring a damaged environment to its natural state is grossly misleading in this context where these lakebeds have always been underwater and are now in this unprecedented exposed state only because of the barrages It would seem that freshwater only ideology is not inconsistent with terminology that misleads and misrepresents the facts There is no place for extremist environmental ideology in the planning and management of this crisis Action must be evidence based and

    Original URL path: http://www.lakesneedwater.org/letters/water-levels-below-sealevel-are-unnatural (2016-02-09)
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  • Questionable Comments - Lakes Need Water
    were 1000 parts per million there would be in excess of 1 000 tonnes of salt dissolved in it This current spike of water say 500 600GL on its way downstream into South Australia with the lower lakes in mind is likely to contain about 500 000 tonnes of salt when it reaches the lake and this amount of water won t be enough to fill Lake Alexandrina even to half capacity To deal with the crisis today river flow would have to be of sufficient volume to both fill the lakes with more than 1000 GL capacity at least 3 500 GL plus a similar volume again to enable flushing the contaminated system out to sea to have any chance of removing some of the salt The Government recognises Futures Paper that 3 500 GL are needed in the lakes to do this That amount of water is not available in the system and is not likely to be available in the foreseeable future with no allowances for growing in the food bowl upstream The salt from the current and expected flows will sit in the lakes only to concentrate with no escape and with protracted drought and next summer s evaporation salinity levels will become even more extreme There is no way to rid the salt from the lakes as they are To deliver much of South Australia s ration to the lakes where some suggest it is sorely needed is irresponsible The pending flows should be kept in the river channel as much as possible Currently these flows are being denied access to the backwaters and wetlands With a weir in place we can exhaust salt out of the river with every flow event into a tidal lake system and out to sea The reality of the

    Original URL path: http://www.lakesneedwater.org/letters/questionable-comments (2016-02-09)
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