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This update published 2nd August 2007
First published 24th January 2005

Recent Events

Introduction

Brief Program History

A Mandated but Unviable Solution?

Stonehaven Media Briefing

The title says it all

Increasingly worrying salinity?

The causes of salinity

Contempt for democracy?

Absence of scientific and analytical credibility

Alternatives to deep drains

New justification for the program - the Coorong

The Blame Game

Introduction

Well, it's official. Climate change is a reality, rainfall will continue to decline for another century, watertables have been falling naturally and dryland salinity contracting for well over a decade, and the case for South Australia's mandated taxpayer- and landholder-funded drain network in the Upper South East should have evaporated into thin air!

In fact, had State Government officials properly monitored the performance of their deep drain trial in 1998, and reviewed the effects on the environment of all previously dug South East drains (required by the program's "officially recognised environmental impact statement"), they probably would have concluded the same in the late 1990s.

The result is that their 14-year preoccupation with a crude, inappropriate, and expensive, solution to a naturally receding problem is causing, not curing, environmental damage in the region. Even more surprising, the mass of greenhouse gases emitted as a consequence of drainage (possibly well in excess of the equivalent of a million tonnes/year of carbon dioxide) far exceeds the mass of salt removed annually by the network!

In the language of project managers, the State Government appears to have become excessively output- focused (on highly visible project deliverables - drains), at the expense of long-term outcomes (eg sustainable agriculture and a healthy environment), which are more difficult to quantify, but are why the program was established in the 1990s.

Defying compelling and growing landholder and scientific opinion that advises to the contrary, the unstoppable drain juggernaut continues to blunder on, with the Government recently awarding a contract to Leed Engineering and Construction to dig the 30km Didicoolum drain extension, the next stage of the network. Leed, poised to start work immediately, was briefed by the Government to expect problems (from landholders?) on the way. The responsible Minister confidently claimed that she did not expect any, until it was pointed out to her that the program was probably illegal! The Minister called a halt to drain digging. A month later, digging has still not restarted.

So how does a State Government with a reputation for acting tough on law-breakers get around this type of problem? By the responsible Minister changing the law to make it legal using a procedure normally reserved for addressing and correcting "minor and inconsequential" matters! At the sweep of a pen, she compulsorily acquired thousands of hectares of land from landholders without any warning or compensation, removed any possibility of legal challenge, and bypassed a process that parliamentarians and legal experts advise should have been put to the State's Parliament and taken a minimum of four months to implement!

As a result of the Minister's actions, Leed was given the green light to start digging again. Landholders, protesting where digging was due to restart again, are demanding an independent inquiry into the program completed so far. A group of 130 protesting landholders had been waiting patiently, except the operators of Leed's excavators did not turn up. The Minister claimed on radio that digging would now possibly start a few days later, presumably in the hope that the protestors will go away? However, the protestors plan a long haul demonstration, and are heartened by offers of long-term practical and quick response support from hundreds of landholders from right across the region.

Read what has been reported in the press, and on TV and radio, about the Didicoolum drain, and more generally on the Upper South East program, by clicking on the links on the media reports webpage.

The program has been characterised for years by contradictions between State Government claims in support of the drainage program, in particular: on the causes, extent and management of dryland salinity and the performance of deep drains; and what landholders have observed on the ground and read in official literature. This resulted in concerns that the causes of, and solutions to, dryland salinity and flooding in the Upper South East have been seriously misunderstood or misrepresented. This website is a response to these concerns.

The website is informally peer-reviewed, and corrections and additions are based on readers' comments. It contains a review of dispersed (in many cases technical) information and reports, with the objectives of exposing and highlighting the contradictions in the Government's claims, and improving landholder understanding of the program.

Information has been provided by landholders, State and Commonwealth Government officers and scientists, and been derived from other official and scientific sources.

The website is subject to ongoing revisions, so please return later to see updates. Readers are also encouraged to continue sending information and corrections to the webmaster for inclusion in future updates.

Brief Program History

The objective of the Upper South East program, as it became known in the early 1990s, was to address a predicted growth in dryland salinity and flooding in the region caused by rising watertables. Deep drains (also known as groundwater drains, with depth generally greater than about 2m - see photographs above for examples) were to be the principal component of an integrated solution to the problems. By 1999, it should have been obvious to the Government that its dire predictions on rising watertables were grossly inaccurate.

The program's proposed solution in 1993 was a $36 million, 270km deep (up to 4m) drain network, which assessments at the time predicted would be high performing and low maintenance, but only just viable, mainly because of the high capital costs associated with its construction, and the low margins expected by landholders after implementing pasture renovation. Two-thirds of government and public submissions on the proposal expressed concerns with, or opposed, it, primarily because of the proposed depth of the drains.

A more detailed description of events in the period 1992 - 1995 can be found by clicking here.

In 1996, the drainage proposal became a $24 million, 450km deep (but presumably slightly shallower) drain network, and Stage 1, construction of a 52km trial drain, was approved. Records also show that watertables started a general falling trend in the region in the mid 1990s, and in 1998 CSIRO reported that dryland salinity had contracted, and covered an area 22% less than in 1992.

A Progress Report produced in 1999 included information on the trial drain. Shortly after, the State Parliament's Public Works Committee approved Stage 2 of the program. Stage 2 involved the construction of three drains, but nowhere in the agency's submission, Hansard record of interviews with Government officers, or in the Committee's final report, was there a reference to Stage 1 being a trial, or indeed to the Progress Report produced a month earlier.

The transition to Stage 2 appears to have lacked any of the close scrutiny and rigour expected following what was supposed to have been a key trial that informed major decisions on subsequent stages of drain construction!

In 2000, a State salinity audit suspiciously reported that dryland salinity in the Upper South East covered the same area as in 1992, although the report acknowledged that watertables had "been falling throughout southern [South Australia] for the 2 - 3 years up until the year 2000". A year later, the Government released the South Australian Dryland Salinity Strategy! Landholders and Government officers will be disappointed that recommendations made in the strategy were not implemented in the Upper South East.

A more detailed description of events in this period can be found by clicking here.

In 2002, a number of scientific and analytical reviews were hastily conducted (probably in response to Commonwealth Government conditions of funding) in support of the final and largest stage (Stage 3) of drain construction. In 2003, the Public Works Committee approved an expanded $45 million, 665km deep drain network.

Experience and analyses showed that the drain network would be lower performing and attract higher maintenance and operating costs than originally predicted. The drainage project was shown to be unviable based on agricultural benefits. When environmental benefits were included, the project became just viable, but the analysis excluded environmental and economic costs that were unavailable for the hasty review. More information on events in the period 2002 - 2004 can be found by clicking here.

In response to growing adverse publicity on the program, CSIRO was invited in 2005 to write position papers that would ensure "a clear message is provided to all Upper South East landholders and to help address the misinterpretation of information". The reports have still not been made available to landholders! The reports were then followed by a number of adverse reports from a State Parliament committee, a Senate committee, and a Commonwealth audit. Click here to read summaries of some these reports.

In early 2007 the program grew again with the addition of a $14.2 million, 200km fresh water connector drains and floodways' network, which had the objective of addressing damage caused to wetlands by deep drains. The project change proposal submitted to the Commonwealth Department of the Environment and Water Resources claims that "part of the 61 gigalitres of surface water that is annually lost to sea" will be captured to "viably reinstate water volumes to [their] natural flow paths and recreate the wetland corridor between Bool Lagoon [in the south east of the region] and the Coorong [in the north west]".

The stated flow of 61 gigalitres/year in the project proposal existed 30 years ago. A study in 2006 using measured flow volumes since 1992 showed that an average of only 15 gigalitres/year would be available for diversion. An earlier study showed that on its 100km journey to the Coorong, surface flows will decline by as much as 75%, and more after the effects of global warning are considered.

Since the program was conceived in 1993, total program costs have more than tripled ($24 million to $82 million), the network has more than tripled in size (270km to over 850km), estimates of benefits have fallen, and as long-term environmental costs have become apparent, the program's viability will have plunged from barely viable to outrageously unviable.

Scope creep, budget blowouts, and schedule delays, have been allowed to occur without any serious attempt to rigorously review and update the assumptions and predictions that underpinned the program in 1993.

A Mandated but Unviable Solution?

Until 2002, an existing and still current Act (227kB PDF file) enabled construction of drains in the Upper South East using democratic principles (§39(2) of the Act). Then, in 2002, another Act (137kB PDF file) was created, which the responsible Minister at the time stated (click here for the Hansard transcript of the debate and search for 'Right. Okay') was only required to ensure the cooperation of just one named landholder in the region! The Minister, as did most other parliamentarians at the time, clearly believed that the network was needed, but that its form must be dictated by the Government.

The new Act was predicated on assumptions that dryland salinity would expand without deep drains, and that with them production of the land would double (search for 'will double' in the Hansard transcript). Both predictions should reasonably have been known to have been incorrect.

The current Upper South East program appears to have evolved out of a conflict between some bureaucrats and landholders over who should control drain digging in the region, without the responsible Government department questioning whether a regional project dominated by drains was even appropriate!

What a few bureaucrats and landholders believed in the early 1990s was an effective solution to the incorrectly predicted growing threat from dryland salinity and flooding in the region, fell well short of its predicted performance, and caused environmental damage.

Furthermore, CSIRO advice to pre-treat saline soils prior to drainage (2.3MB PDF file - refer to final paragraph of page ii for a summary) was not passed on to landholders, with the result that structural failure of drained soils is now being observed in the region (click here (154kB PDF file) and here (28kB DOC file)). These adverse effects were already being reported in official reports to the State Government in 2002, well before the current and largest stage of drain construction commenced.

Note the inconsistency in State Government advice on treating drained saline soils (4th last paragraph of the last link - treatment "usually recommended after soil salinity has been leached"), and that of CSIRO, inter-state and other international advice (some soils should not be drained, and others "will require pre-treatment")!

In 2002, a survey of Upper South East landholders indicated that dryland salinity and flooding were less important land management issues than weeds, feral pests, soil fertility, and non-wetting soils! Wetlands were reported to have been adversely affected by deep drains, because fresh water runoff had diminished, and in some cases replaced with saline, polluted water. Landholders had reported excessive falls in their watertables and a reduction in the availability of fresh bore water for stock and irrigation. Native vegetation was reported to have been adversely affected, in some cases killed, by deep drainage, because of reduced runoff caused by excessive dewatering of soils.

Recommendations made in the 1993 Supplement to the draft environmental impact statement (1.4MB PDF file) and the 1995 Assessment Report (6.5MB PDF file) to thoroughly evaluate the performance, adverse impacts, and viability, of the proposed drain network during the early stages of construction appear to have been given only cursory consideration, or been ignored. The result is a drain network three times larger and more expensive than originally envisaged.

Click on the link to read more about the detrimental effects of drainage on flora, fauna, wetlands, soils, and groundwater.

The new Act went considerably further than the original. It enabled land for the drains to be compulsorily acquired without compensation, landholders to be levied (now $17 million) for their digging, and protected the Government from liability for its actions!

The Act enabled landholders to claim loss in land value as a result of the drains. The Minister at the time claimed that land compulsorily acquired (100m either side of proposed drain alignments) but not needed for the network would be returned after a "short while".

In 2006, an extension to the 2002 Act (23kB PDF file), to enable continued drain construction following numerous delays, was justified using CSIRO advice (click here and search for 'CSIRO') that 90% of the region, considered to be an unattainable target, needed to be covered with deep-rooted vegetation without recourse to drainage. CSIRO in fact advised that 50-90% of dunes and associated areas needed to be covered, which represents only 18-33% of the region! See below for more details.

The new Minister also boasted that no landholders had made claims for loss in land value as a result of the drains. To date, nearly three years after the northern deep drain network was completed (the first to be dug in the current stage of works), land compulsorily acquired for the network but not used, has still not been officially returned to landholders. Claims cannot be made until then.

On the 30km Didicoolum drain extension, a proposed component of the drain network, and which has been a source of considerable controversy and close media attention for more than a year, the Minister claimed that only one in 10 landholders on the route of the extension objected to its construction, but conceded that it would affect landholders more widely. This should have been obvious when a petition containing nearly 800 signatures to stop the drain's extension was tabled in the State's Parliament in November 2006!

A Ministerial submission on the drain extension prepared in 2005 dismissed three reports (all commissioned by the Government) that recommended against its construction, claiming that "there was inadequate assessment made of the observations and trends in watertables and the consequent dryland salinity risks that have been previously well documented in the [Upper South East]". The inference appears to have been that watertables were rising and dryland salinity was still expanding. A review of watertable levels in the Upper South East would have shown them to have been falling generally for a decade, and to have been similar to or lower (in some cases considerably lower) than when records began!

The submission also noted that "some landholders have been expecting a drain for 12 years and not providing one may have adverse political impacts" as a negative impact of not proceeding with drain construction.

A Government decision on whether a publicly-funded drain is, or is not, dug should never be based upon what landholder have been expecting, but on an assessment of its public benefits and value for money. Value for money is determined by comparing short- to long-term (State legislation and policy use the term whole-of-life) economic, environmental, social and equity considerations, ie benefits and costs, of all options or mix of options available.

The decision-making process is described in the State's Natural Resources and Management Act (639kB PDF file), State Procurement Act (147kB PDF file), and in associated policy documents (119kB PDF file). Value for money is not determined by selecting the cheapest contractor to dig a drain, as appears to have been done to date.

Faced with a collapse in scientific support for the program, Government officers have turned increasingly to a few landholders for unscientific and subjective testimonials. This has resulted in unrealistic expectations from landholders who are expecting to have drains dug, and is fuelling an unhealthy division in the community between those who want (but not necessarily need) deep drains, and those who challenge the Government's assertions.

Over the past two years, government grants have been awarded to identify solutions to the causes of soil structural failure occurring near deep drains. Regulators are being installed in deep drains to hold back water and prevent soils from drying out excessively, and the $14.2 million fresh water connectors and floodways component was added to compensate for damage caused by the partially completed deep drain network to the region's wetlands.

And irrigators paying levies to the program (justified because the Government claims they are contributing to rising watertables) have been warned that their water entitlements (for which they also pay a levy) will be cut by up to 75%, because their watertables are falling unsustainably!!!

Based on the experience of similar projects overseas, and adding to the $17 million that levy-paying landholders have already been slugged, operating and maintenance costs of the network are likely to exceed $3 million a year, or at least $1,500 a year for an average 1,000 ha Upper South East farm.

Stonehaven Media Briefing

The following comments are based on a report of the media briefing that appeared in Upper South East regional newspapers in March 2007.

The media briefing on the Upper South East program, given in March 2007 by the State Government at Stonehaven (Padthaway), was a transparent attempt to intimidate landholders and weaken their opposition to the proposed Didicoolum drain extension. Clearly frustrated Government officials tried to achieve this by publicly naming landholders who oppose the extension.

However, after years of inconsistent and contradictory reporting, the Government lacks the credibility and demonstrated judgement to be convincing in its arguments. A few examples that reinforce these points include:

The title says it all

The title of the media report - "Drainage targets met" - and first few paragraphs expose the Government’s real priorities. Milestones are measured in kilometres of drains dug, and not on the area of land rehabilitated or wetlands returned to good health.

The Government also claimed to the media that "250,000 tonnes of salt is being exported from the region each year". However, information in a publicly available document (3.5MB PDF file, refer to §2.3) shows that this statement is not true, at least for the network's discharge into the Coorong. In the period 2000 - 2006, annual salt exports in surface water flows averaged 125,000 tonnes (assuming average release volumes of 8.35 gigalitres a year and salinity of 15,000 mg/L).

Using data from another official, and probably more reliable, source, an average of 110,000 tonnes/year of salt was removed from the region in surface flows in calendar years 2005 and 2006, of which an average 99,500 tonnes/year flowed into the Coorong! The six-year average was 156,000tonnes/year.

While sounding impressive, these figures are less than half of the salt originating just from rain that falls on the region, and flows into the region in groundwater and surface water every year.

When the salt derived from annual rain is added to the remnant salt from thousands of years of earlier rain, to that remaining from when the Upper South East was under the sea a few thousand years ago, to that from natural weathering of rocks and material left after the sea retreated, and to the salt blown in by wind from the coast, even the grossly exaggerated figure of 250,000 tonnes a year becomes negligible, and is certainly not a figure to boast about.

Under natural (pre-European) conditions, salt was removed in the slow groundwater flow to the coast, and by surface water flows that ultimately discharged into the Coorong in the north of the region. These natural flow processes, when combined with the action of rainfall and evaporation, resulted in salts becoming concentrated low in the groundwater profile, with fresher groundwater on top.

Then, introduction of European agricultural practices, especially clearance of native vegetation from the dunes and ranges in the Upper South East, resulted in a major increase in the amount of rainfall reaching the watertable, which in turn pushed up saline groundwater close to the land surface on adjacent flats.

Water several metres below the land surface of poorly structured soils can rise to the surface by capillary action, and salts then become concentrated by evaporation. Insensitive European agricultural practices on the flats, in particular ploughing and over-grazing, resulted in the soil's health and structure suffering, which in turn exacerbated capillary rise, evaporation, and the build up of salts at the land surface.

Rapid surface drainage of poorly structured soils also prevents salts that have accumulated in sub-soils not being effectively leached back to the watertable. A vicious cycle of land degradation causing increasing dryland salinity, causing more land degradation, and so on, then starts, until the root causes of the problem are addressed.

Increasingly worrying salinity?

A Government officer commented on “increasingly worrying salinity”. This statement is inconsistent with what has been observed generally with Upper South East land and recorded in Government reports and data. Rising watertables, which the Government consistently claimed were the cause of dryland salinity, have generally not existed for over a decade. The Government's own records (click here for an overview, and here to see a map of watertable records for the period 1990-2003) show that watertables are now similar to or lower than when records began.

In 2002, only 8% of Upper South East landholders considered they had a salinity problem. Indeed, more landholders rated (in order) weeds, animal pests, soil fertility/nutrition, water repellent soils, and waterlogging as more important land management issues than soil salinity. Soil salinity was rated a land management issue by proportionally fewer Upper South East landholders than for the State as a whole. Click here for the survey report, and refer to pages 9 and 10. Ironically, weeds have been introduced to and spread around Upper South East properties, and other land management issues have become worse, as a result of drain construction!

So watch out South Australia - the case to drain the whole of the State is even stronger than for the Upper South East!

The causes of salinity

In a switch of logic, the Government now wants landholders to believe that lack of water, not a surplus as it previously argued, is contributing to salinity on the photographed “watercourse” appearing in the media report! The photograph was of a region know as the Bluff, and Cockatoo and Clay Lakes, just south of Padthaway. Here, the Morambro Creek flows onto the Marcollat flat, and is where a number of drains also discharge.

For those with Google Earth, go to 36° 46' S, 140° 33' E (type or copy 36 46' S, 140 33' E in the box at the top left of the Google Earth screen, and then click the spy glass immediately to the right). Zoom out or in until the Eye altitude indicator (bottom right of image) reads about 1km. Do this by moving your mouse so the cursor goes to the top right of the image, then click - or + on the vertical slider until the altitude is correct. Orientate the image with ESE at the top of the screen (do this by dragging the compass rose around until the east mark is just left of vertical). Tilt to view at an oblique angle (click the right box of the top right horizontal slider until the Eye altitude is about 260m), and you get a perfect match with the photograph - including a lot of suspiciously white (salt?) land surrounding the wet (blue) areas.

The colour of the vegetation and other features indicate that the Google photograph was taken in August or September 2001, which was a wet year, but salt is still evident!

The Marcollat flat, which the Government proposes to drain with the Didicoolum drain extension, is one of several two to 10km wide flats aligned parallel to the coast about 50km to the west. During wet seasons when the soils are saturated, surface water flows in a westerly direction across the flats, and is then redirected in a north-westerly direction on the east side of dune ranges through remnant wetlands. The Marcollat watercourse is about 6 or 7 km to the west of Clay Lake, but would not have made such a dramatic photograph, as the Google Earth photographs show.

Astute readers of the media report will have noted a major inconsistency in the Government's statements. If both too much and too little water cause salinity, then perhaps there could be another more important mechanism contributing to the problem. The more important mechanism according to some CSIRO scientists is degraded soil health and structure, which, while acknowledged as a contributing process, was over-looked as a treatable cause when the drainage program was conceived.

Saline land rehabilitation based on improving soil health has dramatically reduced the incidence of dryland salinity in other states and overseas.

Salts exist in all soils of the world, and in trace amounts in rain. It is increased concentrations that stress flora and fauna. Salts exist in different forms, being mainly chlorides, bicarbonates, carbonates, and sulfates in the Upper South East. Sodium salts are the most soluble, and are commonly associated with salinity. Less soluble salts, such as calcium carbonate (as limestone), and the more soluble calcium sulfate (as gypsum), also exist in significant quantities in some parts of the region.

Paradoxically, saline conditions maintain a porous soil structure, but salts leached by rain following deep drainage result in soil structural breakdown, erosion, and infertile conditions. When saline soils are drained, sodium ions attached to soil particles cause soil particles to repel each other. The condition is known as sodicity, which primarily affects clay soils and those high in organic matter. Under saline conditions, or where the concentration of sodium ions attached to soil particles is low, individual soil particles attract and clump together to form larger aggregates.

For this reason, CSIRO and international advice is to pre-treat saline (potentially sodic) soils with soluble forms of calcium (typically from gypsum), when the soils are still porous, which is well before soil structural failure becomes evident. High concentrations of calcium applied at this stage ensure that the sodium ions are displaced from the soil particles, and are flushed by rain and surface water to the watertable where they can do less harm.

Salt accumulates in soils when the upward flow of water (through capillary action and absorption by plants) exceeds infiltration by rain and surface water. Salt from rain also accumulates in significant quantities just below the root zone of native vegetation, which can be well beyond the reach of capillary flow from a deep watertable. Removal of native vegetation then results in the accumulated salt being flushed to the groundwater, only to reappear later on lower ground where the land surface is within the capillary zone of the watertable.

This process probably contributed to a significant increase in land and groundwater salinity in the Upper South East after large-scale land clearance and loss of deep-rooted perennial pastures in the mid to late 1900s, and following a period of above average rainfall in the 1980s and early 1990s. However, this transient effect, followed by re-planting the land with deep-rooted perennial pastures, and a return to lower rainfall patterns in the mid 1990s, resulted in watertables falling and dryland salinity generally contracting.

Contempt for democracy?

The Government's apparent contempt for democratic principles (an officer justified the drainage program by claiming that it was a "one-in, all-in kind of thing") should be a concern to all South Australians. The same officer's description of the $82 million publicly-funded program as “just a long ditch that carries salt away (from the region)” was naïve in the extreme, and appears to demonstrate little concern for, or interest in, the collateral damage it is causing.

Another officer was reported to have described the controversial program as attracting “passionate and polarised community views”. He failed to admit that their origins were the Government’s grossly incorrect predictions in the early 1990s on the spread of dryland salinity and the benefits of deep drains, its dismissal of the concerns of many landholders and government agencies who challenged the then proposed 270km drain concept, and its ongoing failure to address inconsistencies between what it reports, and what is being observed in the region and reported in official literature.

Absence of scientific and analytical credibility

The Government's increasing reliance on landholder testimonials to promote the program would be more convincing if supported by credible science and scientific opinion. So where is the scientific support? Suspiciously, about 30 scientific and analytical reports produced since early 2002 have not been released to the public, unlike the copious reports produced before then on the Government's drainage program website.

These missing reports include background papers produced to support the current stage of drain network construction, and a number of CSIRO and other specialist reports on the impact of deep drains on the environment. CSIRO position papers produced at the request of the State Government in 2005 to counteract growing adverse publicity have also not been released to the public. Why not?

A non-exhaustive list of reports and papers produced for the program, but not released to the public or available on the program's website, are listed below:

In 2004, the Government reported (page 8 of 1.5MB PDF file) that salinity was resulting in "estimated annual production losses of $436 million", although this figure appears to have no basis in fact!

If the drain network when completed reverses these estimated losses, then the production benefit ("uplift" is the term used by a Government officer) will be at least $660,000/drain-km, or an average of $1million for every 1.5km of deep drain constructed. The proposed Didicoolum drain extension is 30km long, which should have generated an "uplift" of around $20 million to achieve an average benefit for this public investment. The predicted "uplift" of $1 million is considerably less, which does not remotely represent best value for money.

In 2003, the Government acknowledged in a submission (146kB PDF file) to the State parliament's Public Works Committee that the program could not be justified by the predicted benefits and costs for a hypothetical central "model" farm (see pages 9 and 10 of the submission). The so-called 1,000 ha "model" farm had been used in a post-drainage pasture improvement scenario in 1993 and 2002 to determine likely benefits and costs of drainage.

The program could only be justified by including environmental benefits, but the benefit-cost ratio of 1.38 presented to the committee did not include several caveats from the original 2002 report. The report clearly described the figure of 1.38 as being derived in a process that attributed environmental values that were "not realistic". Corrections for reduced drain effectiveness, environmental damage caused by deep drains, higher capital and maintenance costs, and for more realistic farm scenarios, would probably have resulted in a figure closer to 0.5!

Alternatives to deep drains

At the media briefing, a Government officer is reported to have threatened “there were only two clear choices: complete the (Didicoolum) drain or halt the entire scheme”. Is this another reflection of the Government's views on democracy?

A cheaper and more cost-effective option described by CSIRO in a position paper (57kB PDF file - final section extracted from report) produced for the Government in 2005 was to plant 50% (required to reduce dryland salinity) to 90% (required to revert to pre-saline conditions) of Upper South East dunes and associated areas with deep-rooted perennial vegetation, such as lucerne.

The areas represent respectively about 18% and 33% of the Upper South East program area, or 130,000 ha and 230,000 ha of land with elevation two metres or higher than surrounding flats. Click here (2.1MB PDF file) and refer to Table 1 for a breakdown of land categories in the Upper South East. Replanting this area with perennial vegetation would restore the water balance on the dunes, which CSIRO attributed to rising watertables and dryland salinity on the flats. In answers to questions provided by the State's Environment, Resources and Development Committee in 2005, Government officers acknowledged that an estimated 300,000ha of lucerne had already been planted!!

CSIRO modelling reported in the Government's 2003 National Action Plan Priority Project Proposal for the drainage program predicted that 70,000 ha planted with perennial vegetation would reduce the deep drain network's flows to the Coorong by 20 gigalitres a year. Maximum annual flows without revegetation were predicted to be 63 gigalitres. By simple linear extrapolation, around 200,000 ha planted would have reduced drain flows to zero - that is, no need for a deep drain network! Flows from two-thirds of the completed network (up to 10 gigalitres/year) are well short of predicted levels, so the revegetation required to revert to pre-saline conditions was probably considerably less than 230,000ha.

This advice was consistent with a Rural Solutions (2002) background paper (not released) on regional revegetation targets, and with a mid 1990s PPK paper on managing dryland salinity in the region (4.2MB PDF file). Another 2002 CSIRO background paper on vegetation status in the region (also not released) reported that 13% (considered to be a gross underestimate of total plantings, possibly by as much as five-fold!) of the region had already been planted with lucerne, just in funded programs.

A Government officer's summary (44kB PDF file) of the CSIRO advice appears to show that it was misunderstood. The summary concluded that 80 - 90% of the land surface of the Upper South East needed to be planted with perennial vegetation in order to control rising watertables and reverse dryland salinity, which "was considered to be an unattainable target".

The officer's interpretation was then used to justify the continued digging of the drain network by the responsible Minister in late 2006! She stated that "CSIRO land and ground water specialists who have modelled ground water processes in the new scheme have indicated that 90per cent—and I stress 90per cent—of the area in the region would need to be covered with deep-rooted vegetation, both native and pasture, to manage the recharge from annual rainfall effectively without recourse to drainage. This was considered to be an unattainable target, and it was therefore considered that a complementary engineering solution would be necessary to redress the imbalance, namely, a surface and ground water scheme to assist with discharging water and salt from the region."

CSIRO in fact advised that "during the initial period [of trying to achieve the perennial vegetation cover target], the use of engineering [ie deep drains] to protect valuable land or environmental areas may be considered"!

Click here and search for CSIRO to see the context in which the Minister's statement was made. The Minister's statement also contradicts State Government publicity (2.3MB PDF file) on the program, which claimed that 50% coverage in the region with lucerne was "an effective means of reducing groundwater recharge" in the 1970s. The Rural Solutions (2002) report also referred to "approximately 300,000ha [or about 44% of the region] of dryland lucerne" in the mid '70s "which most likely helped maintain the balance of the area's groundwater system".

The Minister referred to the environmental impact statement for the program, but failed to acknowledge a later Assessment Report (6.8MB PDF file), which, with earlier documents, formed the "officially recognised environmental impact statement". The Assessment Report identified deficiencies in earlier documents prepared for the program, and in particular identified the requirement for rigorous scientific review as the program progressed. It emphasised the need for a thorough evaluation of the performance of a trial drain.

The Government's review of the trial drain (Fairview drain) conducted in 1999 at best appears to have been superficial, and it is clear from reports produced in 2002, which were not made available to the public, (read paragraphs following Telfer) that trial results were never incorporated into any review of the benefits and costs of the program.

When the responsible Minister was informed in Parliament (click on link and scroll down about six headings to the one beginning UPPER SOUTH-EAST) that her interpretation of the CSIRO revegetation advice was incorrect, she ducked the issue and invoked the "REM defence".

REM (Resource & Environmental Management Pty Ltd) is an Adelaide-based "consulting company with extensive qualifications and experience in environmental engineering, hydro-geology, hydrology, environmental science and soil science", which the Government has used to advise on drain designs. A co-author and the peer reviewer of the REM report cannot be described as objective, unbiased or well informed advisers to the Government. Click here to find out why.

The REM report used in the Minister's "REM defence" admitted that there were doubts about the accuracy of the predictions, and recommended that more work be done, including validating drain models using data collected from the Fairview Drain! REM's objective was to investigate deep drain options that would achieve balanced agricultural and environmental outcomes. REM's brief DID NOT involve identifying an optimum solution (potentially involving a mix of shallow and deep drains, soil management, and revegetation) to achieve balanced outcomes.

Landholders who have worked hard to identify these solutions without resorting to expensive and damaging deep drains remain frustrated with the Government's drain obsession.

New justification for the program - the Coorong

Four years ago, an objective of the drainage program was to minimise flows into the Coorong to maintain its hyper-saline state (refer to the Government's 2003 National Action Plan Priority Project Proposal) in accordance with the Government's obligations under the international Ramsar agreement. References to these obligations were recently removed without explanation from the Government's drainage program webpage on the Coorong on 16 March 2007!

Now, according to the Government, the Coorong's survival depends on maximising flows, by diverting fresh water (claimed 20-50 gigalitres a year) to it from the Lower South East through a connector or floodways network in the Upper South East!

Assuming a surface area of around 175km2, the Coorong loses about 250 gigalitres of water a year just in evaporation, so potential annual drainage flows of 20-50 gigalitres, if they exist, will barely make a difference. Recent recorded Lower South East surface water flows are more like a tenth of the Government's claimed figures, and that is before it even starts its slow, meandering journey of over a 100km to the Coorong.

The likely impacts of polluted drain water (see for example the media reports webpage, and look for articles on Lake George) on the ecology of the Coorong, as well as other Upper South East wetlands, is just not worth the risk. An expert on the Coorong's ecology also does not believe it is worth the risk (click here to view the media article).

Heneker (2006) modelled surface water flows potentially available for diversion to Upper South East wetlands under different rainfall, runoff and diversion scenarios. The study used historical records of rainfall and known flows, which were corrected for reductions in runoff arising from reduced rainfall (caused by climate change) and the increasing effects of plantation forestry.

Heneker noted that a reduction in rainfall of 10% (experienced in centres in the Lower South East over the past 50 years, and a trend expected to continue until the end of this century) may result in reductions in surface water runoff by 30-40%. Reduction in runoff caused by plantation forestry (increasingly significant in recent years) is related directly to the percentage of catchment area planted. This is currently estimated to range from 3% (Mosquito Creek catchment) to up to 30% (Southern Bakers Range/Drain C catchment). Banking and contouring associated with plantation forestry is expected to further reduce runoff.

The average annual flows of Drain M, the major source of water being considered for diversion, was 61 gigalitres 30 years ago, 31 gigalitres 10 years ago, 5.3 gigalitres in 2005, and for the year ending 2006 probably less than 2 gigalitres, under the influence of a drying climate trend and the establishment of blue gum and pine plantation forestry.

Drain M was dug in 1964, linking Bool Lagoon in the east of the South East to Lake George on the coast in the west, effectively cutting off half of the catchment to the major Upper South East watercourses in the east (Marcollat and Bakers Range). The Fairview drain dug in 1998 in stage 1 of the Upper South East program then cut off the catchments for the West Avenue watercourse. The ultimate destination for water flowing along these watercourses would have been the Coorong.

While wetlands in the Upper South East might benefit from diverted surface flows, the trade-off will be an average 50% reduction in flows to Lake George. This is likely to attract significant community opposition, because of concerns that reduced Drain M flows have already caused the Lake's current poor health.

Use Google Earth to navigate and zoom to the centre of Lake George at about 37° 24' S, 139° 59'E (type or copy 37 24' S, 139 59' E). The most striking feature of the view is the unhealthy, dark green colour of the lake, compared with the clear water in the two coastal lakes to the north. The Drain M discharge point can be seen on the east side of the lake's southern most lagoon, and the drain's route traced back to its origin at Bool Lagoon in the east.

Based on data for the period 1992 to 2004, the estimated average surface water available for diversion to the Marcollat, Bakers Range and West Avenue watercourses would have averaged 15-20 gigalitres/year, and varied between 0 and 40-50 gigalitres/year. For future years with similar rainfall patterns, surface water flows would be less when corrections are made for declining rainfall and increased plantation forestry.

The Fairview drain, which is a proposed link in the connector to the West Avenue watercourse, is currently a groundwater drain of limited capacity (maximum design flow less than 200 megalitres/day), with recorded annual average flows of about 6 gigalitres/year and salt loads averaging 37,000 tonnes/year. Fresh water diverted along the Fairview drain to the West Avenue watercourse would need to be in excess of 12 gigalitres/year to reduce average water salinity to around 2,000 mg/L for the wetlands. Fresh water flowing down the Fairview drain is expected to cause major erosion of its sodic clay banks, and thus downstream turbidity is also likely to be an issue.

Potential flows reaching the Coorong were not estimated by Heneker,but will be considerably less than those entering the Upper South East, as water is lost filling intermediate wetlands, lost to groundwater recharge, and is taken up vegetation. Furthermore, the water's journey of up to 160km from Bool Lagoon through some of the most pristine Upper South East wetlands to the Coorong, will result in enormous losses to evaporation. Total losses in the wetting and drying cycles of various wetlands were estimated to be of the order of 20 gigalitres/year (DWLBC (2002)).

Modelling of the impact of the greenhouse effect reported in Table 3.3 Part 3 of NRC (1993) (4.8MB PDF file) predicted a "considerable reduction in surface water flows", with losses in flows into the Coorong being up to 75%.

Whenever high surface flows arising from high rainfall are available from the Lower South East, the Coorong is unlikely to need them because high rainfall will also result in increased River Murray and deep drain network flows.

On balance, the connector and floodways' concept appears to have merit, primarily because of benefits to Upper South East wetlands that lie between the Coorong and the Lower South East. However, the Government's intention to link the connectors and floodways' concept directly to the construction of deep drains on neighbouring flats attracts high risks for the wetlands. If the connectors and floodways fail to deliver flows of sufficient quality (based on past experience of the Government's predictions, a highly likely event), deep drains on neighbouring flats will result in the remaining Upper South East wetlands being deprived of their only source of fresh water.

The connector's proposal has the appearances of a desperate attempt by the Government to create a new justification for a deep drain network that should never have been allowed to proceed in its current form. The Government's claim that the survival of the Coorong depends on the proposal is nothing short of deceitful, emotional blackmail of landholders who oppose construction of the deep drain network.

The Blame Game

The blame game started in 2005 when concerned officers of the State's Department for Environment and Heritage publicly contradicted the Government's official position on the drain network, and highlighted the environmental damage that drains were causing. Click here (210kB PDF file) for a Hansard transcript of their concerns, and here (1.3MB PDF file) for a copy of their presentation.

In the same year, a State Government officer claimed that CSIRO's report on damage to soils (2.3MB PDF file) caused by deep drainage was too difficult to understand, so its advice (first reported in the mid 1900s) that saline soils proposed for drainage needed to be pre-treated was not passed on to landholders. Landholders are now observing soil structural failure as a result of not pre-treating their soils. The pre-treatment cost (or cost of post-drainage repair) was not included in the economic analyses for the program.

The same officer also wrote that inappropriate measurements of aquifer properties made by the State Government in 1992 was the reason why newly constructed drains were under-performing. The Fairview trial drain under-performed by 80%. Some northern catchment drains constructed in 2004 were over-designed by a factor of up to 10X, according to one program officer.

At a public meeting in 2005, Government officers contradicted each other over whether watertables were falling or rising, when official records clearly showed they had been falling for a decade in the region.

Consistently, the public and parliamentarians are told by the Government that the drainage program addresses 15-year old community concerns over the threats from dryland salinity and flooding, but they say nothing of the fact that the concerns were whipped up by its grossly incorrect predictions on the expansion of dryland salinity, and the exaggerated benefits of deep drains.

Concerns expressed in two-thirds of the region's landholder submissions (a third opposed the network) on the 1993 proposed 270km drain network, reports in 2002 that the deep drain network was causing environmental damage and was probably uneconomic, and that proportionally fewer Upper South East landholders than for the State as a whole rated dryland salinity a problem or an issue, have also never been mentioned.

More recently, some landholders and Government officers blamed Federal Government-promoted plantation forestry in the Lower South East for reducing surface water flows to the Upper South East's wetlands. And the forestry industry hit out at the State Government, and more recently the South Australian Farmers Federation, claiming they wanted to wipe out bluegum plantations in the South East.

The Government is also not acknowledging blame for the adverse effects of 150 years of State-sponsored and -mandated drain construction, that diverted water away from the Upper South East's wetlands and the Coorong directly out to sea. This includes the 1998 Government's construction (funded by mandated landholder levies, and State and Federal taxpayer's money) of the 55km Fairview drain, which diverted water away from some of the nation's most pristine wetlands.

Nor any words said about decades-old Government-mandated clearance of native vegetation from the region, which led to rising, saline watertables in the 1980s, and to structural breakdown of soils that were drained.

Government officers have referred to past practices causing the land to become "highly modified" (a euphemism for "highly degraded"), which they use to justify modifying (or degrading) it even more. They say nothing of the fact that the State Government sponsored, and in many cases mandated, the practices that led to the degradation of the Upper South East's land and wetlands, and which they are intent on repeating again.

Possibly even more significant, no comment has been made on the region's long-term decline in annual rainfall (over a 100mm in 50 years in the central South East), on CSIRO's predictions that the decline is likely to continue until at least the end of this century, or on the enormous effect this will have on watertable levels, and on surface water flows for the region's dying wetlands.