The Saga of the Lincoln Basins
THIS SUBMISSION WAS PRESENTED TO THE NATURAL RESOURCE COMMITTEE (NRC) PARLIAMENTARY INQUIRY INTO EYRE PENINSULA WATER SUPPLY UNDER PARLIAMENTARY PRIVILEGE BY THE EYRE PENINSULA WATER ACTION GROUP
There are four basins that together are included under the title “Lincoln Basins”.
Generally they are freshwater lens lying over seawater. With the removal of the upper layer fresh(er) water, the seawater-freshwater interface tends to rise. While some authorities might know in detail how far down the interface actually occurs, this information is generally not available to the community. The underlying concern by people who are concerned about the ecological sustainability of our basins is that the freshwater in the Lincoln Basins may be declining to the point where little remains, and the seawater is closer to the surface than we are being told. Any dramatic increase in saline water in any of these basins would make them unusable for decades.
What follows is a presentation of the information that EP Water Action Group has been able to accumulate about the basins from what is on the public record, along with the questions that arise from the data presented.
FROM THE PARLIAMENTARY INQUIRY
The graph shown below was presented by Ben Bruce, Director of Science, Monitoring and Information from the Department of Water to the Parliamentary Inquiry into water management on Eyre Peninsula on 4/5/2012.
Ben Bruce’s comment regarding this graph he presented was (page 4 of his submission):
“Moving on to the issue that people are concerned about in terms of the up-coning within the Lincoln Basin (try to suspend the green line; this is a diagram taken out of another paper), you will notice the red line, which shows the measure of salinity, and the blue line, which shows pumping effort. You can see that there is a very strong correlation between salinity level and pumping, and that’s simply because as you draw water out you draw the more saline water up. You will also notice that once the pumping stops it drops back down to about a background level. SA Water has certainly modified the way it uses this lens to accommodate that, so it is very closely managed in that regard.”
The ‘another paper’ Ben Bruce is referring to is called ‘Saltwater Intrusion into the Southern Eyre Peninsula’ (front cover of document is illustrated below) and the graph is found on page 32. The authors of the document are James Ward, Adrian Werner and Brenton Howe.
The first thing that an astute observer might notice is that the graphs only go from 1993 to 2003. Why is that, when there must be data extending from 2003 right up to the beginning of 2012?
The second observation is that Ben Bruce is using figures that are nearly 10 years and older – and no recent salinity readings are included.
This raises the question: how can Ben Bruce say to the Parliamentary Inquiry that “SA Water has modified the way it uses this lens to accommodate [the salinity up-coning], so it is very closely managed in that regard”?
It would appear that there is NO current data provided and SA Water will not release their individual pumping extraction rates.
Without more recent data to back up the claim by Ben Bruce then it is possible that we are being misled. We would like to see the corresponding data for the last 9-10 years presented to the Parliamentary Inquiry. We would like the Natural Resources Committee ask Ben Bruce for the evidence that SA Water has continued to modify their use of this lens, keeping in mind that there have been continual increases in salinity since 2003 and SA Water will not provide pumping extraction rates.
Yet another question arises: the document that includes this graph was published in 2009, and the figures for the graph were at least 6 years old then – why weren’t more up-to date figures used?
Another interesting point is the claim that the extraction rate is “approximate”. Why is that? Why can’t the exact volume of extraction be used?
It also states that the measured salinity is from Production Bore F. This leaves open the question: how are all the other Lincoln Basins Pumping Bores performing?
To gain more information one of the authors of the Report was contacted and we were told that SA Water had provided the data. They also hold the extraction rates. He went on:
“These are really interesting observations; it is rare to have dynamic data such as this. I have substantial research in the area of saltwater up-coning, but have always had trouble getting salinity data for pumping wells – I’m not sure why. We conducted a stack of lab experiments to get the images below, which were the first published accounts of these processes observed under controlled experimental conditions”
Below are the images provided by that author, which show the salt water as the purple colour. (the fresh water floats on saline water because the saline water is heavier).
The images show a pump suspended in the fresh water and illustrates from (a) to (f) on how the saline water (purple) is drawn up or upcoming up from excessive pumping. Removal of storage component of the fresh water above will cause the level of the purple area(saline water) also to rise.
The map below shows the location of the two bores (from Ben Bruce’s graph) in relation to the sea:
On the map above the salinity reading Lincoln Pumping Bore ‘F’ was 1,083 TDS (9/2/2010), SLE 037 was 29,774 TDS (4/12/2009) (tertiary bore) and observation bore SLE 068 7,046 TDS (14/12/2011) (which is located near the seawater interface) up nearly 4,500 TDS since first drilled (a massive salt intrusion).
This map also shows the approximate distance between the bores, and the current levels, current salinity and bore numbers all highlighted in yellow.
SLE-037 is defined as a tertiary bore, i.e. it measures water at the tertiary level and not at the quaternary level, which is closer to the surface. The readings indicate the salinity level is close to the salinity of seawater.
Below is the salinity graph of ‘Production Bore F’, which is the bore, referred to in the graph presented by Ben Bruce.
It shows just how many times SA Water has pumped out water above 1000 mg/L (TDS).
Any time this occurred after the introduction of the WAP (in the year 2000) is contrary to the conditions laid down in the WAP for extraction.
At the very least the EP NRM Board should have been notified and ongoing management discussed with them.
The graph also shows how many times the salinity was measured from 1960 until 2010 (the latest data on Ground Water Data website).
Note, that the lenses included in the Water Allocation Plan are mapped according to water salinities below 1000 TDS (the standard used for potable water and for water dependent ecosystems).
Why go to the trouble of having these lenses mapped for salinity <1000 TDS for the protection of the ecosystems etc. when SA Water and EPNRM totally ignore this and pump water way above the 1000 TDS?
What is the point at all of trying to protect these ecosystems?
Below is the same graph as above but showing the salinity in EC units (uS/cm)
Notice that from 1993 until 2003 (highlighted in red, see above graph) THERE ARE NO READINGS ABOVE 3000 uS/cm. This is contrary to the graph presented by Ben Bruce (covering the same period) that has 17 readings above 3000 uS/cm (see below).
From the graph above (the one presented by Ben Bruce) the ‘pumping rate’ and the ‘water level’ of Bore SLE-037 have been ‘removed’ leaving only the ‘salinity’ levels of Production Bore F.
All this raises the following questions:
Why has SA Water pumped water that is not only over 1000 TDS (~ 1810 EC (uS/cm) but also up to and above 7000 EC (uS/cm)? Is this not salt mobilisation?
They measured it at about 5000 uS/cm (approx. 3000 TDS) during December 2000 and continued pumping until the salt level was above 7000 mg/L in 2001, after the new Water Allocation Plan was officially signed off by the Minister.
Has SA Water ignored their general statuary duty of care referred to in the Acts?
The Water Allocation Plan for the Southern Basins Prescribed Wells Area states on page 17,18
13. Water shall not be allocated if the rate of underground water extraction will cause, or
will be likely to cause, the salinity of the water measured at the proposed point of
extraction to exceed the baseline salinity by more than 100 mg/L.
14 For the purposes of this Plan, “baseline salinity” means the existing salinity of the
underground water at the proposed point of extraction.
20. Water may be allocated to be taken from more than one point of extraction within the
same Quaternary Limestone lens where:
(a) variable conditions of the aquifer would render it impossible to extract water from
a particular point on a continuing basis;
(b) that the water to be taken from each point of extraction will not:
(v) adversely impact upon an ecosystem;
(vi) cause salt mobilisation;
The graph below shows the salinity levels of the same Production Bore F from Obswell for the same period 1993-2003 (please note the graph below only goes from 1998-2003) because there were no readings at all between 1993 and 1998.
From looking at the table below, it was SA Water that measured and sent the data in to Obswell. They have obviously not sent in all the readings or are all the other readings just been fabricated? What is really happening here?
Below in the table it shows in yellow the dates when the salinity was measured and by whom, and seven readings from Pumping Bore F for those 10 years (1993-2003).
Highlighted in red below is the unit number and drillhole name. The drillhole name is “LBPBF” (highlighted in red) stands for Lincoln Basin Pumping Bore F. (This the production bore F) Notice on the graph above, which is from the new Groundwater Data website (which replaced the old Obswell), it has the unit number in the top left corner and is recognised as a SA Water town water supply (SA TWS), but it does not have Lincoln Basin Pumping Bore F in the ‘name’ section (the name “LBPBF” has been removed). Is this so the average person can not recognise which SA Water pumping bore is which?
On the graph below we have had the salinity readings for Production Bore F (from Obswell) superimposed by us (the blue line) on the graph of salinity readings (in red) of Production Bore F presented by Ben Bruce. They should be exactly the same – but they are NOT! Why not? One has about 73 salinity readings and the other 7 for the same period 1993-2003. If the Groundwater Data website is true and correct (with 7 readings) where did all the other figures come from and why have they not been recorded?
Not only is there a discrepancy in the amount of readings, most of the figures DO NOT MATCH. Perhaps more importantly the seventeen high salinity levels above 3000 (uS/cm) approx. 1,800 TDS (way above potable water levels) are NOT recorded on Obswell (for the period 1993-2003). WHY NOT?
Below is a comment from Ben Bruce recorded during his presentation to the Parliamentary Inquiry:
Ben Bruce also stated in a letter to a member of the community copy of letter available if required) that;
The Department of Environment, Water and Natural Resources (DEWNR) is committed to providing timely and useful groundwater information and has launched Groundwater Data, a one-stop-shop for well (drillhole, bore) information. The new online application is fast and easy-to-use, enabling users to find important information about groundwater across South Australia. It combines the former Obswell Internet and the Drillhole Enquiry System (DES) applications so that information can be easily found in one place.
So why is all the well data of the salinity readings of Production Bore F not available on the Groundwater Data website?
If Ben Bruce says they make all well data available to the public, why has SA Water not provided Obswell with all the other readings as well, – or was the pumping of 7,000+ EC (uS/cm) too embarrassing?
This raises an issue of grave concern: can we trust the data SA Water is providing, not only here but in relation to other water extractions on Eyre Peninsula?
IMPORTANT EPA MONITORING BORE NEAR TO THE SEA
We have also noticed SLE 068, a monitoring bore located near the sea (see previous map showing PROPER BAY SEAWATER), is in fact an ‘EPA’ observation bore.
Why have the EPA allowed extractions to continue despite knowing the salinity was at such extremely high levels in such an important observation bore?
The guidelines of the current water Allocation Plan state “Monitoring of underground water levels and salinity adjacent to the coast to determine the required
amount of through-flow to the ocean and to gain an increased understanding of the recharge processes.”
During that 12 year period of NO MONITORING the salinity increased from 2,750 TDS (29/5/1997) up to 12,011 TDS (26/5/2009).
Why was the monitoring of such an important bore not done for approximately 12 years? (see the graph below of SLE068).
THE NEEDS OF THE ECOSYSTEMS
The following statement below, from the “Southern Basins Prescribed Wells Water Allocation Plan” (page 3) in the section titled ‘Assessment of Needs of Dependent Ecosystem’ states quite clearly; one of the main objectives, the needs of the ecosystems, the maintaining of storage water etc.
Please note if the storage component of the Basins are maintained the Water Allocation Plan says it will buffer climate induced fluctuating recharge (in other words climate change or periods of low recharge).
The table (immediately below) titled ‘Summary of Assessed Needs of Ecosystems’ is from the Southern Basins Prescribed Wells Water Allocation Plan (page 7).
We draw your attention to the importance of maintaining the water quality (salinity) that is needed for these important ecosystems (note the various marked ecosystems in yellow) can only be sustained if the QUALITY OF THE WATER IS LESS THAN 1,000 mg/L (TDS).
On page 12 of the Water Allocation Plan under the section No. 4 on the ‘Capacity of the Resource’ it has a table of all the volumes of water available for extraction (including SA Water for public water supply) and states on page 14 “The listed volumes represent ONLY underground water resources with a salinity OF LESS THAN 1,000 mg/L (TDS).
How can SA Water possibly be allowed to extract water above 1,000mg/L (TDS) when the volume of water given them is specifically meant to be <1,000mg/L?
Finally in the section 5 Water Allocation Criteria (page 16) it states below
Please note the NUMBER ONE objective in water allocation criteria in the Water Allocation Plan is ‘SUSTAINABLE USE’ of the underground water resource.
SALT WATER INTRUSION!!!
Below is a quote from the Department of Mines (South Australia) document ‘Lincoln Basin Investigations Preliminary Report’
by R. G. Shepherd Geologist 18th August, 1959.
As long ago as 1959 it was considered important that regular monitoring of salinity be done to DETECT ANY MOVEMENT of saline waters: in this case he recommended QUARTERLY (3 MONTHLY) monitoring.
R. G. Shepherd also quoted “The direction of movement of groundwater is southerly in the area north of Sleaford Mere and westerly in the eastern portion of the basin. There are apparently several outlets (of water) although the only visible sign is THE SPRINGS near the head of Proper Bay.
Another quote from him states
The important emphasis to note here is that there MUST be NO appreciable rise in salinities due to movement of surrounding or underlying saline water.
Bear this is mind when you are looking at all salinity graphs of all the SA Water pumping bores in the Lincoln lenses, which are displayed later in this presentation.
This map segment immediately below was taken from ‘Understanding the Southern Basins Prescribed Wells Water Allocation Plan’ (page 7) and the black arrows show the direction of movement of underground water flows and the red arrow placed by us, indicates approximate location of SLE 068.
Also from the same document (page 8) in the section ‘Lincoln Basin’ it states, “DISCHARGE from these lenses is EVIDENT as SURFACE SPRINGS near Tulka springs.
Do these springs flow or even exist today and if they do, what are their current salinity readings?
These are part of the ecosystems identified in Water Allocation Plan (page 7), see table (Summary of Assessed Needs of Ecosystems) previously displayed in this presentation, as having water requirements of <1,000mg/L (TDS).
The monitoring section of same Plan (page 29) states; “The monitoring of points associated with significant ecosystems and underground water DISCHARGE POINTS, using environmental indicators and associated underground WATER LEVEL and QUALITY measurements.” It furthers states; “Monitoring of underground water levels and salinity adjacent to the coast to determine the required amount of through-flow to the ocean and to gain an increased understanding of the recharge processes.”
From the salinity levels at SLE068 there appears to be a massive salt intrusion in this area in complete contradiction to the requirements of the Water Allocation Plan and what occurs naturally.
Has over extraction and ignoring all the water dependent ecosystems requirements caused the natural discharge of the basin here to be reversed?
EPNRM AND PROHIBITION ON THE LINCOLN BASIN
The following question was asked to ANNIE LANE (CEO) EPNRM by a community member in January 2012 (the community member has a copy of these questions and answers if required).
“Why is there not a Prohibition on the Lincoln Basin so it ensures it complies with the NRM Act?”
Annie Lane failed to answer the question, so another request was made and the answer was;
“Sorry, did not realise you were seriously looking for answers. I will address your questions when I am back in the office next week.”
Finally a reply was received which stated this question will be discussed with the Department of Water Resources and the Board’s Water Resources Advisory Committee but the question remained unanswered and until this day no response or answer has ever been received.
EPNRM BOARD AND THE WELL-MANAGED WATER RESOURCES?
The following question was asked in February 2013 by a member of the community to the EPNRM,
“How is it that the Board does not (or cannot) comment when a member of the department publicly claims “that I think what the evidence is showing is that at this stage (water) is being well managed” when in fact Polda has been drawn down to the extent that it is unusable for 4 years, has been closed for another 2 years, and could be closed for longer, Uley East Basin is diminishing, and the Lincoln Basins are in a perilous condition?”
The following answer was received from Heather Baldock, Presiding Member (EPNRM).
“The Board believes that the groundwater resources are being managed within the guidance of the current Water Allocation Plan (WAP). Furthermore, the Board believes that management of the Eyre Peninsula’s PWAs continues to be proactive and responsible”. She continued to say “there is no evidence to support your claim that the Uley east and Lincoln basins are diminishing or in a perilous condition”. She then stated in part of her answer, “The report does acknowledge that the Lincoln Basins in the 2011 report did indicate a low risk, as there is an adverse trend in groundwater salinity (e.g. increases in salinity levels). This is being monitored.”
EP water Action Group have noticed that no recent salinity readings are on the Ground Water Data website for the Lincoln Basins since December 2011(almost 18 months ago) and the latest readings on the website for the SA Water pumping bores in the Lincoln Basins were in February 2012 (over 12 months ago).
In fact no salinity readings for the Lincoln Basins have been placed on the website since the Parliamentary inquiry commenced in May 2012. Coincidence?
How can the EPNRM Board say” this is being monitored” and when there has been no monitoring of the observation bores for nearly 18 months? The Southern Basins Prescribed Wells Water Allocation Plan states (on page 27) in the section on monitoring requirements “This section of the plan outlines a system providing for the regular monitoring of the capacity of the prescribed water resource to meet the demands for water on a continuing basis.”
The Plan also states (page 27) “Monitoring underground water salinity fluctuations, with strategic wells monitored on a MONTHLY basis.”
“Monitoring underground water salinity levels at the end of December and June of a water-use year.”
How can Heather Baldock, the presiding Member of the EPNRM state “The Board believes that the groundwater resources are being managed within the guidance of the current Water Allocation Plan.”
Why have the monitoring requirements not been followed?
Are we, the community, being misled?
IS A LICENSEE ALLOWED TO PUMP WATER OVER 1,000 mg/L?
A member of the community asked these questions below in August 2012 and the reply came back from Ben Bruce, the Director of Monitoring (copies of the questions and answers are also available).
“I know in the ‘criteria for allocation’ it does not specifically mention about environmental needs (except recharge water and more than one point of extraction)
but it is addressed in other sections of the Musgrave WAP.
Are the needs (environmental) of groundwater dependent ecosystems taken into account when giving out allocations to licensees?
For example if any licensee which is pumping water has their salinity increase above 1,000mg/L would that licensee still be given an allocation considering that the needs of some of the groundwater dependent ecosystems water requirements in the Musgrave WAP are <1,000mg/l?
In other words is there a maximum level of salinity a licensee is allowed to pump above 1,000mg/L when the groundwater dependent ecosystems require <1,000mg/L?”
Ben Bruce’s replied saying;
“You have questioned whether there is a maximum level of salinity a licensee is allowed to pump above 1,000mg/L when the groundwater dependent ecosystems require <1,000mg/L. There is no provision in the Musgrave Prescribed WAP preventing licensees extracting water above 1,000mg/L.”
If this is the case Ben Bruce, what is the point of identifying and mapping lenses of <1,000mg/L?
What Ben Bruce failed to state, that there is a duty of care to maintain these basins <1,000mg/l to comply with the WAP and the environmental requirements.
In part 7 of the document ‘Understanding the Southern Basins Prescribed Wells Area’ and in particular section 7.1 ‘Breach of license’ it states
“ALL WATER USERS, including for stock and domestic, have a responsibility to manage and use the water resources sustainably and efficiently. This is to protect the ENVIRONMENTAL, social and economic needs and benefits that EXISTING and FUTURE USERS receive from the water resources. It is in EVERYONE’S INTEREST to COMPLY with the WATER ALLOCATION PLAN’S POLICIES”.
LATEST SALINITY READINGS FROM THE SA WATER PUMPING BORES IN THE LINCOLN BASINS
The EP Water Action Group has downloaded the series of graphs below (from Groundwater Data) of the latest salinity readings of the fifteen SA Water pumping bores in the Lincoln Basin (see map below). The pumping bores are identified as brown numbers e.g. LBPBA (Lincoln Basin Pumping Bore “A”).
LINCOLN BASIN “A” LENS
The map above is close up section of Lincoln “A” Lens illustrating the location of the pumping bores.
In the series of graphs below we have identified in blue of the name of the pumping bore (e.g. LINCOLN PUMPING BORE ‘A’)
Also the particular lens has been identified in blue e.g. ”A” LENS.
On the graph there is a horizontal blue line drawn by us to illustrate the 1000 TDS (mg/L) salinity level, which identifies the parameter of each lens.
It can be clearly seen that most current readings are above this level, so those graphs that have salinity readings above 1,000 mg/L (TDS)
we have classified them as “NON-POTABLE WATER”. That is also written in blue.
The latest salinity reading for this pumping bore was nearly 1,200 mg/L (TDS) in 2012 and has an increasing trend over time.
This is the first of 2 bores, which are actually having a salinity reading of <1,000 mg/L but only just.
Please note the salinity increase since the commencement of the current Water Allocation Plan in 2001. Last salinity reading was nearly 1,300 mg/L (TDS) in 2012.
This bore is the second pumping bore below 1,000mg/L (TDS).
The latest salinity reading is nearly 1,350 mg/L (TDS).
This pumping bore has witnessed a massive increase in salinity up to currently nearly 1,600 mg/L (TDS).
LINCOLN BASIN “B” LENS
This is the bore Ben Bruce referred to in his Parliamentary submission.
This pumping bore has exceeded 1,750 mg/L (TDS) (Ben’s graph shows it far higher) at one stage during the time of the Current Allocation Plan. It did drop below 1,000mg/L (TDS) soon after, only to rise again.
Is this entire highly saline water ending up in people’s gardens and drinking water supplies?
Please note very little monitoring done on this bore with the last reading (2000) before the commencement of the current Water Allocation Plan.
Another pumping bore with one salinity reading of around 2, 000 mg/L (TDS) and is currently above 1,000mg/L (TDS).
This pumping bore is being over extracted causing salt mobilisation witnessed by the spikes on the graph.
LINCOLN BASIN “C” LENS
The latest readings are nearly 1,200 mg/L (TDS) and it appears that the salinity levels are permanently above 1,000mg/L (TDS).
How much of Lincoln “C” lens is left below 1,000mg/L?
This pumping bore appears to be around 1,100 mg/L (TDS). The increase is of concern seeing it is identified in the lens area of <1,000 mg/L (TDS).
Once again a pumping bore with many salinity readings above 1,000mg/L (TDS).
The pumping of this bore should be turned off until salinity readings stabilise below 1,000mg/L (TDS). Latest reading is over 1,300 mg/L (TDS).
The document on ‘Understanding the Southern Basins Water Allocation Plan’ Section 2.3 Underground Water Level and Quality Trends (page 21) states;
“The Lincoln Basin is the resource MOST susceptible to INCREASED SALINISATION when OVER EXTRACTION induces underground water mixing with the adjacent seawater.”
It also states (on page 29) in section 4.4; “The allocation of underground water will be taken ONLY from the recharge component of the resource, NOT from water held
in storage, in order TO PROTECT the integrity of the aquifer”.
Whilst few of these graphs are close to 1,000 TDS or under, many of the graphs not only exceed, but also stay above for some considerable time.
This is apparently contrary to the intent or policies of the current Water Allocation Plan.
It appears that no one has drawn attention of this issue to the EPNRM Board and if they have nothing has been done.