Thank you for watching!
Welcome to the Science Exchange here in beautiful downtown Adelaide and tonight we've
had a discussion on the science behind the headlines of the Murray-Darling Water. If you
are what tuning in from home and you have a question please follow the conversation on
the Twitter hash tags, hash M-D-B plan or hash R-I-A-U-S. We look forward to hearing
from you wherever you are and of course ladies and gentlemen here in the audience you will
have the opportunity towards the end of the evening to ask your questions of our expert
panel. What are we talking about? How do you measure a river? How do you determine what's
important and what's not and how do you make everyone happy? Where does the science fit
in and how do we use it towards making better decisions while also making sure that the
river remains a valuable asset for Australia? Tonight we have an expert panel to discuss
the science behind the Murray-Darling River and the plan that has been put together for
it. Ladies and gentlemen my first speaker tonight, my first guest is director of the
Murray-Darling Freshwater Research Centre based in Woodonga, Victoria. Previously he
was officer in charge of the Mildura Laboratories for the Murray-Darling Research Centre before
becoming the director of the centre in 2002. Ladies and gentlemen would you please welcome
to the stage Dr Ben Gorn. Welcome. Let's go right back to basics Ben because it would
strike me that at the core of it the science behind managing a river is working out how
much water goes in and how you divide it up but it's more complicated than that isn't
it? Absolutely and that's why a few years ago the government had to commission CSRO
to undertake the sustainable yields project just to work out how much water was in the
system and what we might expect in terms of where that water was going to go and flow
under a variety of climate scenarios. So just knowing how much water there is on both surface
and groundwater is incredibly complicated and then working out how to divide that up
between the various uses is also incredibly complicated and part of the challenge with
that is that no matter what you do with water somewhere in the basin it will have cascading
effects on someone else or something else somewhere in the basin. So how do you actually
go about measuring the water? Is it a case of you just have a lot of rain gauges across
the basin and you add it all up? Well there's the Bureau of Meteorology has now been given
a lot of money to try and develop better environmental monitoring of water flows but essentially
there's both rainfall models which look at the amount of rainfall that falls on the land
and then runoff models that tell you how much of that water should make it into the streams
so that's one source of information but there's also a network of gauging stations in all
our rivers that report and many of them are accessible through the web to give you regular
discharge. Now some of them are a little bit old and not particularly accurate and some
of them fail when they're overtop by floods but that's that network of gauging stations
that provides the information about how much water there is. There's also an extensive
network of groundwater bores that tells people what's happening in groundwater, how salty
it is, whether the levels are going up and down. It must also be difficult in the boundaries
of the Murray Darling. From a hydrological sense they're kind of difficult to define.
You can maybe pick the ridge of mountains as being one particular boundary but when
you go down into the ground as you say you've got groundwater how far down do you go where
that water is actually part of the cycle and indeed how far up into the sky do you go and
measure and try and incorporate what water is going to be coming into the system that
might. Yes and then we make it more complicated by putting pipes and channels into cross boundaries
that weren't crossed before. So Melbourne and Victoria just constructed a pipeline to
ship water out of the basin, the snowy scheme shipped water into the basin. So yes there's
also other connections and then there's the wildlife and birds that responded a continental
scale so they don't really respect the basin as an ecological entity. They had to cross
the continent, the migratory birds had up to Japan and Korea. Yes there's connections
both from a water perspective and biological perspective with the continent and with the
globe. And not wishing to sort of jump too far ahead in the discussion at this point
but the question of making people happy is anybody happy with the plan you've come up?
I haven't met anyone who's been particularly happy and I don't think in this sort of exercise
it's realistic to expect anybody to be happy. This is about making trade-offs and so I think
it's inevitable that it doesn't matter what you end up with, that no one's going to be
entirely satisfied. So the art of compromise is not making everyone happy, it's having
a solution that everyone can live with. But it's also recognising that this is not about
developing a magic bullet or a magic answer around this. It's part of a process. We got
here 200 years ago, we tried to make the best of the landscape and the resources that are
available to us. We didn't really know what we were doing. We've now got a whole bunch
of unintended consequences and we're saying, okay, this isn't where we wanted to be, we
want to be somewhere else. But we're not going to get there with one piece of legislation
or with one turning of a tap. It's a process we're on and we're going to, you know, the
Basin Plan is an important part of that process but it's not the end of the story. We will
continue to improve our knowledge of the system, we'll see what the consequences of this reform
process are and then we'll review it and we'll come back and say, is this giving us a social
economic and environmental value? If it isn't, there'll be more reform. But, you know, it
is a complex system and you can't just tweak it, you know, there's no magic bullets, unfortunately.
Okay, well let's bring another expert onto the stage, ladies and gentlemen, currently
emeritus professor at Monash University and member of the Murray Darling Authority. Yeah,
you can move along one if you like. No, no, that'll be good. Ladies and gentlemen, welcome
to the stage, Professor Barry Hart. Barry, you spent some time at CRC Freshwater Ecology
and so perhaps you could be the person who could explain to me what is meant by environmental
flow? What does a river look like when it has a good environmental flow? It looks like
it is at the moment. There's plenty of environmental flow going through most of the Murray Darling
basin at the moment. The big challenge that we've got is that, as Ben said, we've modified
the flows, particularly in the southern basin, which I think the majority of these people
are most interested in, we've really modified the small to medium sized floods. We can't
do much about the big ones and there's lots of flooding going on at the moment, but certainly
those medium to small to medium floods, they're the ones that the dams capture and they're
the ones that are very important. So they're the flows that would go into a wetland, a
floodplain, perhaps once every two years, once every four years. That sort of frequency
is taken out pretty much. But then, as you said, we've modified the rivers so extensively
that environments like River Redgum, for instance, which require regular heavy flooding in order
to, or rather irregular heavy flooding in order to germinate the seeds, they're not getting
what they need to perpetuate. Well, it depends on where you are. Certainly,
if we just focus the moment on the southern system, the area between Lake Hume, say, down
to about Swan Hill or maybe even a little bit further, that tends to get reasonable
flooding, reasonably regular flooding. And there's some modifications, of course, that
have been done to Barmer and Gunbar and a couple of the other areas that gets water
on to those floodplains. It's the area further down, so from around the Mildura area, down
into the Riverland, the South Australian Riverland, that really is being starved for
those large overbank flows. And with respect to environmental flows, the current plan,
I gather, came out with a number of 2,750 gigalitres as being appropriate for the environmental
flow. But wasn't the original estimate between 3,000 and 4,000 gigalitres, and why did it
change? Well, the original that came out in the guide was actually larger than that.
It was a fairly, I'll go back to the one in which the methodology we've used now, but
the original methodology was one where we really just looked at what was the end of
system flow from each of the catchments coming into the main stem and allocating a proportion
of that, which brought it from around about the 3,000, it's a little bit more than that,
to about 7,000 odd. We looked at the impact, a very reasonably cursory look at that stage,
at the impact of that on the communities and the irrigators and decided, and this is the
trade-off that was talked about before, there are a number of those, that 4,000 was really
as far as we could go there. Subsequently, we've done a heck of a lot more, much more
than Premier talked about science. The underpinning science that's behind what's out now is hugely
better than that fairly broad brush approach that was used originally, and that's a large
amount of modelling, a large amount of science that's going into the particular assets, the
particular areas that the flood plains, wetlands, the rivers themselves that we believe need
water, and we have to decide, it's all very well talking about an ecosystem, what do you
actually mean by that ecosystem? So it comes down to birds, it comes down to fish, it comes
down to the red gums, it comes down to a number of other components of those systems, which
go to then make up the overall biodiversity of the ecosystem.
But in its natural state, 100% of the water would have been environmental flow. So has
the evolution of the science behind the water management been a case of how much we can
take out for other purposes, or has it, it seems to me the way it's involved is actually
the inverse of that, that we've taken out whatever we've wanted for irrigation, for
industrial uses, whatever. And now we're saying, well, we've actually got to take something
back from those other uses. How do you quantify what those units are?
Well, I think there's no question that the scenario you just painted there is exactly
what's happened over the last 150 years, that the major focus has really been on consumptive
use. And we actually, and Ben can back this up, I'm sure, that we have really failed in
terms of really working through all of the science that we need. We've got a reasonably
large basis for science. I think it's a very good start to be able to put the basin plan
into context at this stage. But as a scientist, I would not say that we're in really, really
good shape. There are many aspects, particularly the relationships between flow and what does
it mean for components of the ecology. So we've still got a lot to learn there.
If I can just interject, you sort of mentioned natural, and no one's sort of talking about
getting back to natural. The basin plan is very clear about trying to protect and restore
the environmental values that we currently know that are described in the basin plan,
and that's largely around biodiversity. So preserving the diversity of species and preserving
the diversity of ecosystems within the basin. So that's a very different prospect to actually
restoring the whole system back to anything like natural. It's saying, what are the diversity
of ecosystems we've got? What are the diversity of plants and animals? How many of them do
we have to maintain for the next generation to be able to enjoy them or export them in
the same way, which is what sustainability is all about. So there's some really challenging
questions there in terms of science of how many regent parents do you need to minimise
the risk that they'll go extinct during some catastrophic time in the future. And it's
those sort of questions that science has really got to grapple with if we're going to achieve
that protect and restore objective. We've been using the term science a little
amorphously so far. It's a matter of the science, what the science says here. And describe
for me what that science is. Are we talking about raw data of rainfall tables? Are we
talking about studies of ecological systems? And are we talking about models of how they
operate? What is the science that we're talking about?
Look, all of those, all of those. There's no question at all about the two major components,
the hydrology that has been majorly changed, as I described before. And what does that
mean for the ecology of those water-dependent ecosystems? They're the two main ones. But
some of my colleagues on the authority would also argue that there is additional, I'm
pretty sure that's what the Water Act envisaged when they used the words best available science.
We've expanded that, if you like, to also include social sciences, which really weren't,
it wasn't envisaged very much, I don't believe, in the Water Act. And if you like, the economic
sciences.
How do you incorporate the social sciences?
How do you feel about the river of surveys, type things, right?
The ecological science.
No, the social sciences.
Well, look, that comes back, let me set the equation. The equation, I think, is very much
about returning more water to the environment. It's a relatively simple equation. At the
same time, minimize the social and economic impacts. Because as Ben says, there's no way
we're going to go back to natural. We've got a system that has lots and lots of components
in it, lots of communities, lots of irrigators, lots of production, et cetera, et cetera.
So that is the equation. More water for the environment. Now, then you come back to what's
a reasonable amount, how are you doing it, and what are the reasonable minimization
of the impacts. That's where the social science mainly comes in, social and economic, is in
terms of the impacts on communities and the irrigation community from readjusting the
existing system, which is out of balance.
All right. Speaking of out of balance, let's balance up the panel. My third guest tonight,
ladies and gentlemen, a member of the Wentworth Group of Concerned Scientists and previous
Chief Science Advisor to the Australian National Water Commission. Would you please welcome
the stage, Dr. Richard Davis. Richard, how do you think the conversation's been going
so far?
I think the issues you've been raising are exactly the issues that need to be talked
about and exposed. This last discussion of combining social science with the physical
and ecological science is really important because all that information's got to come
together before decision makers can make a decision on how to allocate the water to one
use or another. I think the hydrological, physical science is quite strong actually
in Australia and I think the Murray-Darling Basin Authority has pulled together most of
the information, a couple of missions perhaps, by and large most information in that area.
Ecological science, somewhat less so, we know less and it's much harder to predict. It's
a more uncertain area but when you get to the social science area I think that has been
neglected both in the collecting of information and then the bringing of it into making decisions
about the plan.
Now you're with the Wentworth Group of Concerned Scientists and their principal mission is
the welfare and the science behind the welfare of the Murray-Darling. You were originally
involved with the Murray-Darling Basin Plan but then you guys pulled out and you pulled
out because you didn't like the science. So again, what did that science look like and
what were your problems with it?
I think the primary issue for the Wentworth Group was not the science itself. As I said
a minute ago, the physical science in particular is quite strong in that area. It's the decisions
around the science and how it's going to be used that I think is our principal concern.
How so?
Okay, let me give you an example. There's a lot of uncertainty about what you will get
if you provide water back to the environment. Will these river incomes recover or not? Will
the fish breed or not? Will the birds breed? A lot of uncertainty in those sort of areas.
So given all that uncertainty and given the difficulty we've had for many, many years
now in trying to recover water back for the environment, once you give water away, it's
very, very hard to get it back. That's one of the fundamental lessons we know from the
Murray-Darling. Given the critical moment we're at now, where we've actually got money
available from the federal government, we've got a legislation and a plan that's been
put together, this is the moment to get it right because we're not going to have this
opportunity again for a very, very long time. That means that we've really got to err on
the side of giving, if necessary, too much water back because we can always return it
to the consumptive side if we have to. It's very hard to return it to the environmental
side. Now given those sorts of parameters that are around the decisions, we would hope
to see that the science that underlies the plan is being used in what I'd call a wise
way. But unfortunately, it doesn't appear to me to be as wise as it could be. For example,
the noise has pushed to try and reduce the amount of water that's been returned to the
environment. So we start at 7,000 gigalitres in some scenarios. We work our way down to
4,000 gigalitres. 3,000, we're now at 2,750 gigalitres. It's always in that direction to
try and be as negatively as possible about how much is returned at a time when I think
we need to return more because we can always give it back to consumption if we need to
later on. So that's a sort of surrounding issue that's of concern to us.
So you guys are on the other side of the fence?
I don't know about that, but can I just...
We're on the other side of the stage anyway.
We're next to it. Can I just take up Rich's point about getting it right now? I'd challenge
that. I don't think that's really feasible. And that's why we've extended, if you like,
the time between hopefully when the first basin plan will be accepted later this year
and 2019 when everything kicks in. Lots and lots of things will be kicking in. And we've
built what we hope will be an adaptive plan and that recognises that you don't get it
right first up. Goodness, what about the consumptive use? They've had 150 years supposedly to get
it right and there's still lots of things that can be done very differently there.
So I think it's really important that you can challenge whether in fact we're going
to be able to really roll out an adaptive process, but that's really what we're going
to be trying to do. And I think that's the way to do it. There are some challenges and
there are some risks, but this is a basin plan. I think the Premier was a little bit wrong
when he said the authority now has all of the authority to do this. It won't work without
a very close interaction with the States and with local groups.
That actually touches on a point that I wanted to bring up and that is the teeth of the Murray
Darling plan, if you like. I've heard a cynical presentation that because it's a federal initiative
trying to interact with the States that it's not so much got teeth as big in that the most
effective legislation base that they can operate from is the Ramsar Convention, which is about
migratory birds. It's an international convention that their signature is to. And so the biggest
leverage that the feds have got in the whole process is actions that can serve areas where
birds are breeding and therefore that's the biggest stick that can be wielded in trying
to get a plan through. Have I been talking to one too many cynics?
Well, I think that's a little bit cynical. There's no question that international treaties
– Ramsar and a few others by Diversity Treaty – they loom large in the Act. But there
is some teeth in the Act, not beaks, that allows the authority to do certain things
in various States. But I would say that if we ever had to use that, then something's
failed. So I think where things are going at the moment, there'll be the wrangles between
the States who have got legitimate concerns about their own patch, as it were, where we
have to try to breach that is to look at the system as a whole. And that's why we were
set up. It's a challenge in our federal system, but we'd be failing if we didn't
really challenge that very strongly. Richard, what would it take to get the
Wentworth Group back into the fold, as it were, to get them back into the whole process?
Can I take some notes here? You've got it all on film.
Oh, all right. What are your major objections that prevent you from going back into that
table? Well, I think what I raised before would be
certainly one of them, that if we could see that the MDBA and the Federal Government – and
in fact all of the governments – were willing to take a more, what would I say, risk-free
approach, so that instead of trying to give as little back as possible to the environment,
which I think is what is being the pressure, it's always coming down at the moment, they're
willing to be more generous about that, with the understanding that the adaptive approach
that Barry talked about would truly kick in, and there would be adaption. But when you're
pushing it down the whole time, I very much fear that when the review in 2015, for example,
and that's a moment for adaptation to occur, I would be very surprised. I've not seen
it in the past, where suddenly water was given back to the environment again. It's always
in that one direction. So as I say again, I think the moment is now, when we should
take a more generous approach to the water that the environment is going to need, because
that one-way direction can kick in through the adaption process later on if needed.
I think the real disagreement here is not around the science. The disagreement between
the Wentworth Group and the MDBA is really around the assignment of risk, and how much
risk we're prepared to apportion to the environmental assets that we're trying to protect versus
the social and economic assets. And I'll be free and admit that the science at the moment
is quite weak at articulating what the risks are for the environment. So if we do take
the adaptive approach, and if we say, well, we're going to screw the environment down
to this because we think it's the bare minimum, what are the risks around that? How likely
is it that it's going to be successful? Whereas from the social and economic side, and particularly
the economic side where people have very strong feelings about the risks that they're facing
in terms of loss of towns, loss of industry, loss of jobs, they're able to very clearly
articulate the risk. But it does seem that that risk gets acknowledged and taken into
account. Whereas because the science is very poor at saying, this is how much risk you
face taking that decision for the environment side, it tends to get overlooked. And it's
like you run through a process of, in order to describe the flow requirements for a red
gum forest, you tend to run to an average flood return interval. And then instead of
that just being a guide around which you need to have variation, it becomes the rule. And
so you say, well, we're going to have a flood every three years of this megalithus and that
will keep that red gum forest happy. That's not true, but we aren't good at telling,
you know, being part of the conversation about where are the risks in this equation and who
should bear them and should they be born equally between the various users of the system.
The chair of the Murray-Darling plan, Craig Knowles, said that you used to use an end-of-system
flow model and that that was too simplistic. What's he talking about and what have you
moved to?
Well, that's what I was trying to get to before, that in the guide, because of time constraints,
we did use an end-of-system flow. So it was basically going back to what the models say
it was like before development and apportioning a certain amount of that. And it became 60%
came to about the 3,080% of natural, came to the 7,000. So that's how simplistically
it did. Is that okay there? Can I just add to what Richard said before? I set up the
equation before that has another component that I should have mentioned. So we've got
the science, what's the environment need with all of the difficulties that Ben's just
talked about? What are the social and economic impacts? And that's got its own list of uncertainties
in there. But equally, we've got a set of constraints. This is a system, and you'll
see that all of that we've talked about is a healthy working river. That acknowledges
– well, actually we talked about a healthy working system, which is talking about a broader
system, socio-economic too. But if you look at that, we've got a series of constraints.
We are not permitted to have overbanked flows that flood private properties. We cannot put
an environmental flow down and flood Shepparton or Mojure. Mojure is pretty hard to do. It
went with. So they are constraints. They are real constraints in the system at the moment.
And that's part of what we would see as the process between 2012, 2015 and ongoing to
try to get a number of those constraints. There are physical constraints. There are
bridges you can't flood. There are properties you can't flood and townships you can't
flood. There's constraints about the actual reservoirs that we cannot let enough water
go out of them. There are constraints in terms of the rules that have been developed over
100 years of almost a total looking at consumptive users and not the environment. The way the
rivers are run pretty well totally for consumptive use. Then down south, irrigators need the
water in summer basically. The environment needs it in winter, spring.
Can I respond to that?
Yes, please.
This has been one of our concerns also, Barry, that these constraints really exist. There's
no question about that. You don't want to flood Shepparton. There are bridges that
go under. But remember, there's $10 billion that Commonwealth Government has put up to
help put this plan into place. Now, when you think about that, these constraints start
to look less serious. If you really wanted to, you can shift that bridge. You can raise
the bridge. You can do other things to let more water out of these dams. So some of these
constraints will always be difficult. I agree. You don't ever want to be flooding Shepparton
or some of the other towns.
I thought you were going to suggest you could teach the people of Shepparton to swim.
That's right. But there are other things that you can adjust. And there's a lot of money
on the table available to do this. So to see these constraints as being at the end of the
day what holds us down to 2,750 gigalitres is quite artificial, I think. And I'd be more
convinced of a plan that, as I say, took this optimistic view about getting water back to
the environment, knowing that we can return it later if, in fact, we gave too much back
for the benefits we're going to get, and overcome some of these constraints with the funds that
are available. And I'd be more optimistic about a plan that took that approach than
the plan we have and the attitude that we have at the moment.
With so much at risk in this debate, and there's so much heat rather than light at times, how
readily does the science get lost, and what can you do to defend the science behind the
Murray Darling plan?
You're looking to me. I think the science now is pretty much lost. Certainly we've been
going around the whole of the basin with public meetings and lots and lots of roundtable discussions.
And many, many issues come up. But the primary ones are about communities. The impact on
communities. That's the thing that's really, really high in that.
Coming back to what Richard says, there's a number of issues that the Murray Darling
are not trying to cop out here. The Water Act allows us to do certain things and not
to do other things. The $9 billion that Richard talks about is not in our grubby little hands.
It's in the Department of Environment's hands.
I didn't say that in New Zealand. And it's being challenged. In a number of ways. There's
been some changes. The local communities, I'd say, are pretty much against the buyback
process and the government have modified that slightly. They would rather most of the money
going into infrastructure. But it's irrigation infrastructure, not some of the other infrastructure
that Richard's identifying. I think all of those have to be on the table.
Our biggest problem is not that we don't recognise those situations, is how do we put it into
a statutory legislative act. Richard, can you sell the science of why an
environmental flow is important to an irrigator? I can see that most of them would think that's
just water going down the river that I could be using on my crops.
Absolutely not. I mean, I can show you around 50 irrigators around the middle of an irrigator
who are absolute fans of environmental flows. It's part of a program with the Murray Wetlands
Working Group and Wetland Care in South Australia as well also did things like this where they
used irrigation infrastructure to deliver environmental water into black box depressions.
The farmers who were part of this program thought it was fantastic. They were just so
happy to see their wetlands come back to life. When it started off, there was a lot of community
resistance but by the time it had been running for a few years, the community was coming
around to the idea that this could deliver benefits to them on their farm and they were
major supporters. Is that a one-off or is there a growing
awareness of the importance of environmental flows and if so, then why is it such a difficult
question? I mean, I'd agree with Ben. I think irrigators
are not homogeneous and not homogeneously against this at all and this has been your
experience obviously Barry too. The program that Ben was talking about is on private lands
so these are wetlands that irrigators have on their property and they can see for themselves
out there in front window the benefit. When the birds come, the trees start to grow again,
they can immediately see the benefits and that's why they're so strongly supportive of the
use of water for these environmental outcomes. When you get to the other environmental and
the larger environmental assets, the big wetlands, the Hatter Lakes, the Chawilla Wetlands, these
sorts of areas that you don't necessarily look at out of your front window, you need
to make clear to whole communities now the local benefits to the tourism industry as
well as to the local recreation of people who can go to those areas. If you can do that,
then I think you can definitely sell it and we know that. You can definitely sell it.
The problem has been, what Ben alluded to before, showing that this much water will
lead to this outcome, that you will see those trees or you will see those birds, that's
always a bit difficult because that's the part of the science, the ecological science
that is probably the weakest I suspect of all the scientific information here.
But it's also a vexed issue because it is so complicated. In some cases you're arguing
about people's values. So some people just, they don't care about the environment, you
know, the irrigators are not homogenous, people in cities are not homogenous, but they just
don't, you know, the environment for them is a separate entity and there is no relationship
between their well-being and their quality of life and the environment. Now, I think
scientists should be doing a better job of actually articulating what that relationship
is to make it clearer that we believe that there is a fundamental relationship between
the quality of the environment and the quality of life. But then there are other arguments
there about, you know, is the quality of the science adequate? There's arguments about
the application of that science and how you make decisions and in the end there's going
to be decisions about the trade-off and as I was saying before nobody's going to be entirely
happy with that trade-off. But it has struck me that, you know, there is a very loud voice
coming from the irrigation industry opposing the basin planet least elements of it. But
the second biggest industry in the basin is tourism. And have we heard a voice from the
tourism industry saying, you know, if you don't have a healthy environment, we don't
have an industry? You haven't. And I know that the reason for that is that the tourism
industry is so disparate. You know, you've got some people promoting canoeing, you've
got other people promoting vineyards, you know, it's a disparate industry and therefore
it's hard for them to find a single voice. But they're just as much a part of the picture
as the irrigators and just as much a part of the picture as the environment.
Ladies and gentlemen, a lot to contemplate. We're going to take a 10-minute break and
when we come back, we'll be hearing from the media how they've been dealing with Murray-Darling
water issues and what they have learned from the discussion of the science tonight. But
before we have our little 10-minute break, ladies and gentlemen, let's get a big round
of applause, please, for Ben, Barry and Richard.
