July 1, 2025 • 52 mins
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In today's episode, Margie Dickson, Environmental Project Manager at Healthy Land and Water, takes us on a journey through her experience leading an innovative project on the Caboolture River which re-establishes mangroves for long-term bank stabilisation and ecosystem resilience. This effort combines her engineering expertise with nature-based solutions, including the use of hardwood logs, strategic earthworks and mangrove revegetation to combat erosion. The project is not only addressing critical environmental risks like acid sulphate soils but also exploring how nature-based solutions can serve as alternatives to traditional 'hard' engineering approaches, increasing climate resilience and creating fish habitats.
Our favourite thing about this project, and Margie's approach, is the way she combines immediate engineering solutions with long-term ecological thinking — rather than building the concrete barriers of the past, the goal is to reinforce banks by creating stable angles, placing strategic barriers, and establishing mangrove communities that will eventually take over the protective role naturally. As Margie explains, "Vegetation is always the long-term strategy for keeping our rivers stable and keeping them healthy."
We also explore the fascinating world of mangroves - from their unusual root systems to their vital role as nurseries for fish and habitat for endangered species like the elusive water mouse. Margie shares how these remarkable plants propagate, sending floating "propagules" (not seeds!) up and down waterways, ready to take root and transform mudflats into thriving forests.
Margie is a civil and environmental engineer with a passion for protecting and regenerating Southeast Queensland’s waterways. She works on delivering on-ground projects that stabilise riverbanks, reduce sediment and nutrient runoff, and support healthier ecosystems and communities. Today, Margie shares the story of this fascinating project, the challenges of balancing engineering precision with ecological needs, and the importance of working with nature to protect our waterways.
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Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Margie Dickson (00:00):
I'm always looking at the area and thinking
, okay, where does the energy go, where's the energy coming from
and where's the energy going?
Because that's what erosion isessentially it's when you've got
a certain amount of energycoming down the river, in the
water and it's got to gosomewhere.
And erosion happens when thatbalance is off and there's more
(00:21):
energy than the bed and thebanks of the river can handle,
and so then the river justshoots into them.
Dr. Siwan Lovett (00:45):
Hello and welcome to Take Me to the River,
sharing stories and inspiringhope with extraordinary people
who care for our rivers.
I'm your host, Dr Siwan Lovett.
Today I'm joined by MargieDickson , Environmental Project
Manager at Healthy Land andWater.
Margie is a civil andenvironmental engineer with a
passion for protecting andregenerating southeast
Queensland's waterways.
(01:06):
She works on deliveringon-ground projects that
stabilise riverbanks, reducesediment and nutrient runoff and
support healthier ecosystemsand communities.
Margie is currently leading aninnovative project on the
Caboolture River whichre-establishes mangroves for
long-term bank stabilisation andecosystem resilience.
This effort combines herengineering expertise with
(01:30):
nature-based solutions,including the use of hardwood
logs and strategic earthworks tocombat erosion.
The project is not onlyaddressing critical
environmental risks like acidsulphate soils, but also
exploring how nature-basedsolutions can serve as
alternatives to traditional hardengineering approaches,
increasing climate resilienceand creating fish habitat.
(01:53):
Hi, Margie, it's wonderful tobe talking to you today and I
know we're going to be coveringa lot of topics, but what I
first wanted to start with was Iunderstand you have a civil
engineering degree.
How have you ended up inriparian restoration and
conservation?
What's that journey been?
Margie Dickson (02:11):
A little bit of luck and a lot about sort of
community and connections andthe networks you didn't know
were professional, I think.
So I spent my first four yearsout of uni with a civil
engineering consulting firm,which is where a lot of
engineering graduates go, and Iwas in a team that was actually
all about trying to getrecycling infrastructure built,
(02:32):
which is super important, and itwas a really good team.
But, oh my God, biginfrastructure is slow and I
don't think any of the bigprojects I worked on in my first
four years out of uni haveactually broken ground yet.
So yeah, I was just starting toget a little bit impatient and
I kind of thought maybe I'd liketo work on something a bit
smaller and kick some dirt andlook some people in the eyes and
(02:55):
see some things finished.
And I don't think if I'd justbeen looking around on the
internet I necessarily wouldhave picked this job or thought
I could do this job.
But it was actually my oldscout leader who reached out to
me and said hey, you know, thecompany I work for has a team
looking for good people.
I think you're good people.
You should give this a crack,and it was so important, I think
(03:20):
, to have that little nudge ofsomeone who knows you just
enough to give you a bit ofencouragement, a bit of a push.
And I, you know, because hepersonally asked me I read the
advert twice and I thought longenough to go okay, I don't do
that, I don't know some of thosethings yet, but wow, I would
really like to.
That sounds awesome.
Yeah, so I started this job verymuch on the basis that, well, I
(03:45):
started this job saying not,you know, I can do everything in
this list, hire me and I'll beup and running from day one.
It was a I learn fast.
If that's what you're lookingfor right now, maybe I'm the
person for your team.
And it's been so much learningin the last sort of two and a
half years at Healthy Land andWater.
So Healthy Land and Water isthe natural resource management
(04:07):
group for southeast Queensland,so we're involved in all sorts
of things in waterways, ingrazing, best practice, in
helping people in thehorticulture sector, wildlife,
coastal areas, but my teammainly works on restoring
waterways and so that's a mix of, you know, bank stabilisation,
(04:30):
things with earth movers and youknow a bit of an engineering
component.
But also vegetation is alwaysreally important and the
biodiversity side of things, andthat's really been something
that I've learned on the job,which has been excellent.
I've really enjoyed thatjourney so far.
Dr. Siwan Lovett (04:45):
That's just a great story.
It's interesting.
You know, I always say topeople that your networks are
gold, and there's so many peoplethat I've talked to who have
ended up in river management orworking with communities.
That was as a result of someonerecommending them, and I just
think we need to invest in whatI call social capital.
(05:07):
So that's the networks andrelationships, and actually last
week I was at a conferencewhere I gave a talk talking
about how powerful they are, soHealthy Land and Water.
Then you're now working in andyou're out on rivers.
How are you applying your civilengineering training to working
on rivers?
Margie Dickson (05:24):
Can I just have a comment before I answer that?
Yeah, I think I'd really agreeabout the networks, and
something that I tell peopleoften is it's not just the
networks that are kind of in theroom with the glass of bubbles,
wearing the nice networkingclothes and I think that was
what you saw and heard about andgot pushed towards a lot at
(05:47):
university but the networks thatare actually just in the rest
of your life and you know,bringing your whole self to you
know, whatever it is that you'reinterested in, it's still worth
putting time into those andsurprisingly often there are
intersections with you.
You know that journey throughyour professional life.
At least that's definitely beenmy experience over the years.
Dr. Siwan Lovett (06:10):
I love that reflection because I think
you're right.
Often at uni it's presented asyou need to network, you know
when you're in a meeting or youneed to go to this or that, but
in actual fact it's theday-to-day investment that you
make in relationships and takingup opportunities that really,
in your case, has come throughin terms of you know, a scout
(06:34):
leader, I mean, who knew that'sfantastic.
So over the last couple ofyears you've been having a
really intensive course on howrivers work and they move and
you know they cut new pathsthrough areas that sometimes
people don't want them to, or wetake away the vegetation, which
is sort of our naturalengineering.
What have you been reallynoticing about the rivers of
your region and what are some ofthe biggest issues that you're
(06:55):
facing in southeast Queensland?
Margie Dickson (06:57):
Well, I think, as you said, vegetation is
always the long term strategyfor keeping our rivers stable
and keeping them healthy.
But where that vegetation hasbeen lost or removed over the
years, it can be quite achallenge to get it back.
And that's kind of where theengineering component of river
restoration comes in.
It's never your long-termsolution.
(07:21):
You know, we're not trying toturn our rivers into a fixed
concrete structure, butsometimes you need some level of
engineering and design tocreate stability for long enough
for the vegetation to getestablished well enough that
it's then doing that job.
And yeah, learning to look atrivers, understand how they work
, to kind of think like a rivera little bit, has been a really
(07:44):
interesting journey.
And I mean the people whospecialize in that, they're the
geomorphologists.
But I get to spend a fair bitof time either walking the river
with those guys or looking atthe designs they've suggested
and talking that back and forth.
You know, does that make sense?
Can we build it?
And I guess the way somethingthat probably has come from my
(08:06):
civil engineering training andway of thinking is I very often
look at, you know, erosionissues that we're trying to
decide if we should do anything,if we can do anything, how to
fix them.
And I'm always looking at thearea and thinking, okay, where
does the energy go?
Where's the energy coming from?
Go where's the energy comingfrom and where's the energy
(08:27):
going?
Because that's what erosion isessentially it's when you've got
, you know, a certain amount ofenergy coming down the river, in
the water, and it's got to gosomewhere.
And there are lots of places itcan go.
It can pick up the rocks andthe gravel in the bottom of the
river and move them along for abit until it, you know, slows
down and drops them out, or itcan go into the bed and into the
(08:47):
banks.
And if the bed and the banks ofriver can handle that flow
because it's a rocky gorge orit's a really dense forest, then
that's fine, that's, that's agood way of taking energy out of
the water.
And erosion happens when, whenthat that balance is off and
there's more energy than the bedand the banks of the river can
handle, and so then the riverjust chews into them, and that's
(09:10):
essentially what erosion is.
And so then, when we're talkingabout solving it, we're going
okay, how can we get that backin balance?
And there's a few different.
You know parts of the equation,I guess, and you're looking at
what can I influence here, whichone can I change to get that
balance back?
Dr. Siwan Lovett (09:30):
That's a really great description and I
think for people that don'tunderstand rivers, you know it
can be really frightening whenthey're flooding and it can be
really frightening when they seeerosion, but often our reaction
in terms of fixing it is tomove that water even faster away
from our area, whereas a lot ofthe sort of nature-based
(09:51):
solutions that we're looking atslow the water down.
Is that the sort of work thatyou've been doing?
And I understand you've got aproject on the Caboolture River
at the moment.
Can you tell us a bit moreabout that?
Margie Dickson (10:02):
Yeah, absolutely so.
Our project on the CabooltureRiver is nine sites that we've
been working through over abouttwo years.
They're all bank stabilisationof sections of the banks that
were kind of vertical erodingcliffs, and it's come about.
It's funded by the local waterutility because when that dirt
(10:25):
falls out of the side of theriver and into the water it's
got nutrients in it.
It's got nitrogen andphosphorus and the water utility
has regulations around thosenutrients in the river.
And fixing the bank erosion isone of the things that they can
do to help meet the obligationsthat they've got around keeping
the river healthy, to help meet,you know, the obligations that
(10:46):
they've got around keeping theriver healthy.
Most of our sites are down inthe lower part of the river.
So the estuary yeah, thatlandscape is a big flat
floodplain and you can see theriver meandering out through it.
You've got Melaleuca forests orpaddocks or housing
(11:07):
developments in some spots onthe flood plain and then the
river itself is fringed withmangroves and as you get closer
and closer to the bay, thosemangroves and salt marsh take up
more of the the land on eitherside of the river and even while
we're working there is thisbeautiful dense mangrove fringe
along the lot of the river, butthen in some spots that's been
lost and it just hasn't beenable to restore itself Every
(11:31):
year.
The other parts of the riverthat have lots of mangroves they
fruit and there's heaps ofpropagules floating around.
You'll see them sprout up theirfirst two little leaves as well
.
Dr. Siwan Lovett (11:41):
But you know, it's an urban area.
Margie Dickson (11:43):
We've got recreational fishing, we've got
boats going through and eventhat boat wash from fairly small
powered boats kind of is enoughto be a problem for the little
baby mangroves and it's enoughto nibble away at the.
The base of the vertical cliffis, which is what the banks have
now become in the spots thatwe're fixing, and so the so the
(12:05):
bottom of the bank gets nibbledaway and the top of the bank
falls in and then those littlebaby mangroves have gone and
they just don't have the time toget up and sort of be holding
the bank together and beprotecting the bank from that
wave energy.
If they got big they'd be doinga great job, like sections of
the river 100 metres further up.
But it's really hard for natureto re-establish on its own and
(12:29):
I guess that's where thisproject comes in.
So it has a first stage that issome pretty serious looking
construction.
We're reshaping the banks andthat is all about creating a
stable area for then theriparian vegetation to be able
to re-establish, and there'ssort of a flat protected section
at a good elevation formangroves and then a gentle
(12:51):
slope coming back up.
That's got different speciestransitioning from sort of more
salt-loving ones down at thebottom to your kind of overbank,
your eucalypts and othercoastal vegetation up above the
tide level.
Dr. Siwan Lovett (13:07):
It sounds amazing.
It must be a little hazardousat times, because Caboolture is
quite a big river, especiallyout, you know, when you're
getting down toward theestuarine areas.
What sort of people have yougot working with you?
Are you getting, you know,barges with machine on them, or
are you able to do most of itfrom the bank itself?
Margie Dickson (13:24):
Yeah, no.
So are you able to do most ofit from the bank itself?
Yeah, no.
So we're able to work from thetop of the bank and we're
working with an earth mover thatwe've been working with for a
long time.
They've been doing thisrestoration work with Healthy
Land and Water for much longerthan I have and, yeah, this is
their bread and butter.
It can be tricky, but it'ssomething that they've learned
(13:45):
and they know how to do.
Dr. Siwan Lovett (13:47):
So it's a fairly major intervention.
You know, I know for a lot ofour restoration projects you try
and minimise that level ofintervention, but it sounds like
with a cliff that that'svertical and I'm sure people can
think of cliffs that they'veseen you actually need to do
this reforming in a way.
What's the reaction been withlocal community?
(14:10):
Because I'm assuming that thiswork's being done on private
property.
Margie Dickson (14:13):
Most of this work is being done on private
property.
I think there's one site that'sowned by the council.
I'm actually not aware of anyparticular reaction or even
strong opinions from the localcommunity at this stage, other
than sort of one day whensomeone fishing in their tinny
stopped by to say, hey, what areyou doing here?
This looks a bit serious.
(14:35):
But when you're able to explainthat what you're doing is
joining up the gap in themangroves and the whole purpose
of it is to make the river alittle bit cleaner and make a
little bit more fish habitat inamong those mangroves when they
get up, I think people aregenerally pretty comfortable
with that.
Dr. Siwan Lovett (14:54):
Great and, from the perspective of the
private landowner, somelandowners are more difficult to
work with than others.
Is your sense that for theselandowners, they're seeing these
cliffs as problematic I mean,it is their land disappearing
and that they're comfortablewith the ongoing management of
those areas?
I'm assuming that they willneed to fence out their stock
(15:16):
from the area that you'rerevegetating.
Is that the case?
Margie Dickson (15:20):
Yeah, so it's true that when you're trying to
fix, you know, an issue of theriver taking land in a kind of
uncontrolled way, you do need todeliberately take some land out
of production for grazing, andso in this case, it's about
three times the height of thebank, plus a bit more for trees
on top of the bank.
(15:40):
And, yes, we're putting inpermanent fencing around that
and there's some ongoingmaintenance as part of the bank,
and, yes, we're putting inpermanent fencing around that
and there's some ongoingmaintenance as part of the
project as well.
Dr. Siwan Lovett (15:49):
So what would have caused those cliffs
originally?
Like you're putting vegetationback, is the assumption right
that it's been taking thevegetation away that's actually
caused the problem?
Margie Dickson (16:00):
So I think definitely sort of historically
taking away the vegetation isabsolutely part of what's caused
the issue in these spots.
They're also mostly on theoutside bend in rivers, so
that's a spot where the energyof the river moving past is
highest, and so perhaps that'seither why the issue started or
(16:24):
part of the reason why it hasn'tbeen able to heal itself over
time and again.
That's, I guess, why there is abit of a heavier engineering
component in these spots.
Dr. Siwan Lovett (16:35):
And so, in addition to the sort of grading
the bank, are you putting anystructures in?
I know that wood or groins aresometimes used.
Is that happening here as well?
Margie Dickson (16:45):
Yeah, so down on that flat area in the tidal
zone where we're trying torecreate the mangrove forest.
We definitely needed a littlebit more protection for those
baby mangroves as they'regetting up, so that they're able
to be sort of sheltered fromthe boat wash that's coming past
for three or five or six yearsuntil they're big enough to then
(17:08):
be really protecting themselves.
And so we've got an arrangementof hardwood logs pinned into
that flat section and those arebreaking up any boat wash.
That's sort of hitting the bankand it's creating, yeah,
stiller zones, sheltered zones.
Dr. Siwan Lovett (17:26):
And so that's really to protect them so that
they can re-establish.
I'm assuming that are youpicking up fruit from the
mangroves on either side ofthese areas, or are you actually
propagating mangroves that getby a supplier to pop them in?
Margie Dickson (17:39):
Yeah, so that's an interesting one.
On the first the sites thatwe've been through so far, we
have been deliberately placingmangrove propagules on the bench
.
We couldn't actually collectthem from the Caboolture River
because the Caboolture River,where we're working, is
classified as fish habitat A andall mangroves are protected
(18:01):
marine plants.
So it's actually quite heavilyregulated.
What you own aren't allowed todo, so we had to go and get them
from the next river south.
And then there's regulations on.
The regulations for collectingmangroves are different to the
ones for propagating them, so weweren't allowed to propagate
the seeds.
It meant it had to be a sort ofone day at a time strike
mission where you head down tothe pine river and you collect
(18:23):
your buckets full of propagulesand then you trundle back up to
the kubilcha river and you popthem in the ground on the same
day.
Um, which has been a it worked.
It's been a little bit of aninteresting logistical exercise,
but natural recruitment ofmangroves is far and away
bringing in more new little babyseedlings to these sites than
(18:45):
anything that we've planted.
And so for next year's sites,or perhaps the next round of a
similar project, we wouldprobably strongly suggest that
collecting and planting mangroveseeds isn't really necessary if
you've got established bits ofmangrove forest fairly nearby.
(19:05):
We sometimes talk about mangroveseeds.
If you talk to a botanist theywon't say that they actually
call them propagules, becausewhat mangroves make are, I guess
, a little bit more developedthan seeds.
They tend to be quite large,there's a lot of stored energy
in there, they float and they'rereally almost ready to grow.
So we have two main types ofmangroves on the river where
(19:30):
we're working, and one of themmakes propagules that are kind
of roundish, a bit like a reallybig thick 50-cent piece, and
then some of them makepropagules that are more like a
skinny version of your pinkyfinger perhaps, and they all
(19:51):
float.
And so the mangroves, yeah,come into a fruiting season all
together and you'll have thisbig mass fruiting event and lots
of these mangrove propagulessort of bobbing on the tide up
and down the river.
And if they happen to settle ina little spot that's, you know,
at the top of the tide and it'ssheltered enough that the
water's slowed down and themangrove propagules got stuck
(20:13):
perhaps it got stuck behind alog that we pinned on the bench
to help it out then it'll liethere for a bit and it'll pop
down roots into the mud and thatpropagule will crack open and
reveal those first two leaves,and so it turns from this little
floating life raft into a tree.
Dr. Siwan Lovett (20:34):
Amazing.
So have you studied thestructure of mangroves?
I was just wondering about this, because when I see them, it's
like they don't have one stem.
You can see their roots, reallycan't you?
And then they grow up and it'sthey're like I liken them to
making little chambers, or likelittle chapels, almost where, um
(20:57):
, you know, little fish live anda whole range of other things
can can use them as a support.
Um, what have you learned aboutmangroves that you didn't know
before?
Obviously, you're now an experton propagules and I'll never
use the word seed again.
Margie Dickson (21:10):
Oh, I certainly wouldn't say I'm an expert.
I haven't studied mangroves,but I guess, as part of learning
on the job, suddenly I'm payingattention to them in a way that
I wasn't before.
Yeah, when I'm looking at thelandscape that I might be trying
to repair or I'm monitoring,you know our sites after
completion and the differentspecies of mangroves grow really
(21:31):
differently.
You know, one of the species inthis area does have those
unusual roots that you weredescribing, where, yeah, the one
single stem of the tree seemsto start a little bit in the air
and then we've got all thesekind of roots like some kind of
strange tripod reaching downinto the mud.
Others are much more like treeswith one stem coming out of the
(21:54):
ground, but then they'll besurrounded by this bed of little
hard pointy roots poking up outof the mud, and those are
called pneumatophores and theyhelp the mangrove to breathe.
Dr. Siwan Lovett (22:06):
Wow, that's great.
Thank you for explaining thatbecause, as you were saying, I
was thinking about thosesticking up.
They don't look like fun placesto walk through.
Have you been having a bit ofexperience in and amongst the
mangroves?
Margie Dickson (22:21):
Well, yeah, I also try not to walk on those
because they crunch under yourfeet and you feel a bit guilty
about, you know, repairingmangroves over here and stomping
on their, their roots oversomewhere else.
So, um, there's some spots onthe river where we can do the
monitoring by kayak, and ifyou've got a mature mangrove
forest that's already got a bigpneumatophore bed, you know the
(22:44):
best thing to do is not disturbit.
We're not generally needing toget in there, and so I'm mainly
walking on the the muddy bits ofback that don't have mangroves
and trying to figure out why, ortrying to figure out if our
site is helping to bring thoseback.
And then by the time it is anice, established, dense,
difficult to walk through forest.
(23:05):
We're pretty happy to leave italone to do its thing.
Dr. Siwan Lovett (23:08):
You've done your job, then.
What are some of the creaturesthat you've noticed in amongst
the mangroves, that you mightnot have been expecting to see?
Margie Dickson (23:17):
Ooh, we've seen a stingray in the Caboolture
River, which was a little bitunexpected, and a shark.
We have bull sharks in sort ofthe Brisbane River, the
Caboolture River.
Dr. Siwan Lovett (23:31):
We know they're there.
Margie Dickson (23:32):
But it did swim past just on the day that we
were about to kick off the site,you know, walking over, scoping
everything out, writing up thesafety induction, and went we
better put no swimming.
Hey, we'll just add that as asite rule.
Dr. Siwan Lovett (23:45):
And then the sharks went past.
Oh my goodness, that sounds abit scary.
What about in amongst thecanopy?
Are they really importantplaces for birds?
Margie Dickson (23:54):
Yes, mangrove forests are definitely really
important ecosystems on ourcoast.
It's often, you know, quitehard to observe the wildlife
that lives there because it'sreally hard to move through that
ecosystem.
It's not human friendly butit's excellent as a nursery for
the little fish.
It's a protected spot for themto to breed and to grow up.
(24:16):
It's really good for birds.
They're able to move throughthat landscape and then they're
looking for those little fish.
It's absolutely full of littlecrabs.
Um, and I learned recently thisis not on the Caboolture River,
but I learned recently thatwe've also got an endangered
water mouse that livesexclusively in mangrove forests
(24:36):
and builds little nests made outof sticks in among the
mangroves.
That's not one of my projects,but I work on another wetland up
the top of the Sunshine Coastand I was arriving there one day
to do my water qualitymonitoring and ran into someone
from the University of theSunshine Coast, all dressed up,
looking very practical.
I was like, oh, what are youoff to do?
(24:58):
I'm off to check my trap linesand my cameras to see if we can
find endangered water mice inthe conservation park next door.
And he thought he had foundthem, which was really exciting
because that's an area that isvery low-lying um parts.
Large parts of it havehistorically been cleared for
cane, but the sugar cane mill inthat area closed over a decade
(25:21):
ago and some of those cane areasyou know will be underwater
with sea level rise in mylifetime and so there kind of is
planning and work and thebeginnings of a transition, I
guess, for that area underway.
My work's part of that.
The Sunshine Coast Council'salso doing a lot of work in that
(25:43):
space.
For them they're looking atmangrove forests as carbon
offsets and that's why they'relooking for the endangered water
mice in the bits of forest thatare already there, because if
they're there it means that asthe new areas that are being
managed to transition to a newmangrove forest, that'll
actually be expanding thehabitat for these sort of
(26:06):
secretive little critters.
Dr. Siwan Lovett (26:08):
That's a wonderful story.
I didn't know that there was awater mouse, so we have our
rakali, which we really love,which you know we're often
called the water rat.
Margie Dickson (26:15):
but rakali seems to be.
I've just been to.
Dr. Siwan Lovett (26:17):
Rakali as well .
Yeah, yeah, oh, that's good.
Yeah, rakali does seem to becatching on.
I think it's really fantasticthat we're talking more about
the benefits of these areas,particularly.
You know you were mentioningabout sea level rise.
You know climate change is realand the thermal refugia that
areas like thick mangrovesprovide is going to be essential
(26:40):
, not just for critters but alsofor humans too, because it
actually creates a microclimate.
Have you done any work on that?
Has the Healthy Land and Waterlooked at that at all?
In terms of the climatevariability benefits of
mangroves?
I don't think we have.
Yeah, I was wondering with theoffsets, because we're looking
at trying to develop a tool forbeing able to assess sort of the
(27:04):
carbon sequestration benefitsof riparian areas.
We know that they're betterthan most areas because they've
also got the blue carbon and thegreen carbon.
Yeah, so we're also looking atthat.
Tell me a bit more about theother sort of work that you're
doing.
I know that you've got aninterest in acid sulphate soils.
How do they come about and whatsort of work are you doing in
(27:27):
that area?
Margie Dickson (27:29):
Well, the acid sulphate soil management was a
learning curve on the Caboolturejob, simply because it was
there and we had to make surethat we were managing them sort
of safely.
So what acid sulphate soils areis they're a legacy from the
distant past when the sea levelswere different and large parts
(27:49):
of our coast actually wereunderwater, and so they formed
in these hot, shallow seas.
And it's chemistry I am not achemist, but there's chemistry
locked up in those soils that ifthey're just buried, you know,
in layers under the ground, it'sfine, that's all good,
(28:10):
everything's stable, theenvironment on top's happily
ticking along.
But if you expose these soilsto air, they start reacting and
they generate really strong acidand that can then leak out into
groundwater or adjacentwaterways and quite dramatically
change the pH and make it quitehostile for all sorts of life.
(28:32):
So if there are acid sulphatesoils in the landscape where
you're working and they're mostcommon, yeah, along the coast,
sort of less than five metresbelow sea level you've got to be
really careful.
You've got to definitely checkbeforehand and if you think
you'll be disturbing acidsulfate soils, you definitely
(28:53):
need to have a plan so they areregulated um and some of the
sites on the Caboolture River,part of what we were excavating
had an acid sulfate soil risk.
Um, I think, to be honest, oneof the best outcomes that we've
had in terms of small designchanges during the project is we
(29:14):
were able to make some littleadjustments to where that flat
section for the mangroves wassitting, in terms of elevation,
to make sure we didn't disturbthe really nasty acid sulphate
soil, disturb the really nastyacid sulfate soil.
So on, you know, our first bigsite, the, the bank was about
(29:34):
three meters high, so you've gota little bit of top soil at the
top, and then you've got, youknow, ordinary, non-acidic, you
know paddock, and then belowthat there was some soil that
you know showed up as, yeah,this triggers the thresholds for
being acid sulfate, so you'regoing to need to manage it.
But in terms of treatingtreating acid sulfate, so you're
mixing it with something that'sgoing to neutralize that
(29:55):
acidity.
So in this case it wasagricultural lime, and so we had
our soil tests and they said,yeah, this stuff on top, like
it's a little bit, you'll needto mix it with six kilos of
agricultural lime per cubicmetre of dirt.
And then the soil tests go downa bit further and they go ooh.
And then there's this estuarinemud layer and in that layer if
(30:16):
you want to treat it, you'regoing to have to mix it with 100
kilos of agricultural lime percubic metre of dirt.
And that's a lot.
You know it's a lot of stuff tocut in.
It's a lot of stuff to cut in.
It's a lot of stuff to mixthrough it's.
You're just playing with muchnastier material and the option
should always be, you know,whether you're doing restoration
(30:37):
work, whether you're doing ahousing development, whether
you're doing infrastructure, ifyou've got acid sulfate soils,
you should be looking at themand going?
can I work around this?
Can I actually not expose thisto the air?
And so we looked at themangrove forests that we had
upstream and downstream of oursite and we went.
Well, you know our design isone line on the plan.
(31:00):
You know our flat bit for themangroves will be at 0.7 metres
above sea level.
That's where we'll put it.
But when we sort of looked inthe environment where we were
working, we went.
Well, the main species here it'sactually able to grow and
thrive across a wider tidalrange than that, so it can
(31:21):
handle being wetter and it canhandle being less wet.
So for the one sort of, it wasjust the top end of our site
that was showing up theacesulfate risk.
We went I think we can raisethe bench so we just don't dig
as deep.
We don't dig up that reallynasty 100 kilos of lime per
cubic meter reactive acidic soiland we can be confident that
(31:45):
ecologically and functionallythe project's still going to
work.
And so we were able to makethat adjustment.
I think that was a much betteroutcome for the project and for
the environment than you know melearning to treat and manage
and test acid sulfate soils,which I've done for the lower
risk stuff.
Dr. Siwan Lovett (32:05):
I think so, definitely it, you know.
As you're talking about it,though, I'm thinking about the
enormity of this for alandholder who might not be
anticipating that they've gotacid sulphate soils.
I think our knowledge hasincreased so much more now You'd
kind of hope that landholderswould get soil samples done so
that they understand.
You know, what the implicationsare of liberating that material
(32:28):
.
Does it tend to be in sort of aclump, or is it sort of a quite
distinct line in terms of thelayers of soil as you go down?
Margie Dickson (32:39):
It's more like a layer because, like I say, it's
formed at the bottom of theseancient warm oceans.
So it's kind of like everywherethat was the bottom of the
seafloor will have thischemistry going on and sometimes
it can be quite visible in thesoil profile.
But you can't rely on visualidentification.
(33:03):
You should definitely get a test.
But the important thing is, ifyou're not digging them up, it's
actually not a problem.
So you can have theselandscapes and you can grow
crops on the top or you cangraze or you can, you know, have
a non-acidic ecosystem thereand that will tick along quite
happily and that's absolutelyfine.
You only run into issues ifyou're you know digging drainage
(33:31):
, ditches and changing thegroundwater level, or you know
doing big excavation work.
That's when you know this riskthat's been dormant actually
becomes a problem.
Dr. Siwan Lovett (33:44):
So these designs have gone in and you've
done this work.
You've had some big floods.
How are they holding up with?
Margie Dickson (33:50):
uh, with floods, oh, yeah, there was a a couple
of weeks in, uh, january 2024when I think everything I'd
worked on in my time at healthyland and water was underwater,
and that was.
I was sitting there a littlebit nervous.
They're going.
Oh my goodness, if it's all inmorton bay, I might need to have
a little cry and get anotherjob.
But no, it was okay.
It was okay.
Um we were really happy with howour first sites held up during
(34:15):
those january 2024 floods.
It was a it's an important test, um, I would definitely say.
At that point they'd beenplanted and some of the little
mangroves were up, but thevegetation wasn't doing the
heavy lifting.
It was still quite young and itwas the engineering component
of the project that did theheavy lifting in terms of how
(34:38):
those sites fared.
So reprofiling the bank andthen placing those big logs as
well was really important in, Iguess, helping to protect the
plants that were there.
It was also a flood that spilledout onto the floodplain, so it
was.
You know, our site was fullyunderwater and it was flowing
(34:59):
over the paddock on top andthat's actually a good thing in
terms of the amount of energythat the trees on the banks are
experiencing.
Again, coming back to this ideaof where does the energy go
when a flood does break out,into the floodplain, that lets
(35:20):
the energy spread out a lot andit does potentially less damage,
unless we've put importantinfrastructure like people's
homes, on that floodplain, andthen the damage is really
devastating for people.
Dr. Siwan Lovett (35:37):
Yeah, definitely.
And it never ceases to amaze me, actually, when people say I
can live on this floodplainbecause the last big flood was
100 years ago and it's a100-year flood risk and you're
sort of going, yeah, but thehundred-year flood could happen
tomorrow, like just becauseyou've started here, it's not a
hundred years from now.
(35:58):
How do you go about explainingyour sorts of work and the sort
of you know?
From what I'm hearing, it's acombination of engineering
solutions that we can do andthen nature-based solutions,
really, in that we're trying toset nature up to succeed.
How do you go about explainingyour work and why it's important
(36:18):
?
Margie Dickson (36:22):
That's a big question, isn't it?
I think it's a continuousconversation because these are
big ideas and they're trickyideas and there's always going
to be conflict between room forthe river and then room for
people.
So then, that understanding ofthis is where it floods.
(36:43):
This paddock goes underwater,that's okay, is generally a
little bit easier.
Dr. Siwan Lovett (36:49):
So, having done all this work on the
Caboolture, is it sort of a waitand see game now and you're
going back and monitoring,monitoring, what are the sites
looking like?
Are you taking photos and allthose sorts of things?
Margie Dickson (37:01):
yeah, absolutely , and that's one of the really
nice things, I guess, abouthaving done a project that, like
I said at the beginning, it'sunder a regulated framework,
it's paid for by the local waterutility.
It's part of kind of the wholesuite of things that they do to
meet their responsibilitiesaround the quality of the water
(37:22):
in the river, and so because ofthat, there's actually quite
long-term monitoring on thesesites.
Um, we'll be doing it sort offor five years and then probably
another five after that, and Ithink this whole job, one of the
things that's been excellentabout this whole job is the
ability to learn small things asyou go and then apply those.
(37:45):
So I sort of mentioned thatthere's nine sites that we've
been working on over two years.
So even in the constructionphase you go from site to site
to site and you can, you canbring learnings and sort of
improve things as you go, andit'll be the same in you know
that longer term understandinghow the sites develop and that
same water utility is atdifferent stages of developing
(38:07):
up similar projects on otherrivers up the coast, and so,
yeah, the observations of thesesites on the Caboolture River
having been built and maturingare then able to inform kind of
the design for the next rivers?
Dr. Siwan Lovett (38:22):
You know you were saying that example of,
initially you were, you know,going and almost foraging for
proper gills, but this timearound you're sort of saying
actually, no, just just letnature get on with it.
So it sounds like it's a it'scontinuing to go back.
For people living on theCaboolture River or people who
are interested, is there sort ofa site that they can go and
(38:42):
have a look at, either inreality as well as virtually
online, that they can keep up todate with what's happening?
Margie Dickson (38:49):
Yeah, absolutely so.
The first site that we did isat the end of a public park
called Heritage Park.
It's part of the North Harbourdevelopment in Burkengarry East,
but yeah, it is right on theedge of that public area.
I think a park run goes past iton Saturday mornings and it's
(39:10):
one that we did the earthworkson in the middle of last year,
and then the plants have beengrowing up and we've had two,
two really warm, wet summers, soall those trees on the top of
the bank are looking pretty lushyeah, fantastic, that's great.
Dr. Siwan Lovett (39:26):
I was always envious of the growth rates um,
in queensland because I had a.
At one stage I was managingdemonstration sites across the
country and the tasmanian oneswere very, very slow.
The veg was tiny and then I'dgo up to Innisfail and the trees
would just be, like you know,over my head and I'm just going.
Oh, this seems so unfair.
Margie Dickson (39:46):
Yeah, but then you have to do weed control
forever, because it's not justthe trees that grow, well, it's
everything.
That is a very good point.
Yeah, yes everything.
Dr. Siwan Lovett (40:04):
That is a very good point, yeah, yes, okay, do
you have um any advice forsomeone who's looking at going
into this area of work?
If it's an early career personlike yourself, what would, what
recommendations would you bemaking to them?
Margie Dickson (40:14):
I'd definitely be saying go for it.
I do love my job.
I really love the mix ofgetting out in the field and
then sort of being in the officeand planning the next projects.
There is so much that you canknow about rivers and the
ecosystems that go with them.
(40:35):
You need to be always learningand it's also okay not to know
everything.
There is so much there that itreally does take a lot of
different people bringing theirinput to be constantly improving
, kind of what we're doing atour sites, and I think that's
something to embrace rather thanbe intimidated by.
It's definitely something thatI love about my team.
(40:58):
You know we've, and my team andthe people we work with.
So we've got people who worked,you know, on the tools with
revegetation contractors,killing the weeds and planting
the plants, and then have comeacross to be planning those
projects.
We've got, you know, me and acouple of other people who had
an engineering background andthen have come into this space.
We've got people who studiedscience and ecology and then
have come into this space.
(41:18):
We've got people who studiedscience and ecology and then
have come to sort of put it onthe ground as part of the team.
And so, yeah, I think you heara lot in the corporate world
about diversity drivinginnovation and that being really
important, and sometimes itsounds a little bit buzzwordy,
but I look at my team and I lookat my projects and I look at
(41:42):
the other teams in other partsof the country also doing this
kind of work and I think youknow, in our river restoration
space it's so true and it's it'sreally genuinely happening at
that project and team level,because you can come into this
space from so many differentangles and have something to
contribute, so long as you'realso willing to learn.
Dr. Siwan Lovett (42:06):
I think that's a really great summation
because, I agree, I think it'sgot to be collaborative and the
strongest projects are ofteninterdisciplinary.
And I remember someone tellingme you know, oftentimes we have
this view that experts are sortof my way or the highway,
whereas I think it's more aboutsaying, well, I know something,
you might know something, soit's better together.
(42:28):
So it's just a.
It's a much more collaborativeway of going about doing this
work and I can see how you'vebrought in a whole range of
different elements there andit's really nice, because often
we think, oh, an engineer doesthis and a scientist does this,
but in actual fact we're allpeople and we just talk about
what we're doing.
So you know, that, that seems tobe the success here.
Margie Dickson (42:49):
That was something that I was surprised
to learn about.
You know my job as I starteddoing it in the construction
management space, like whatwe're doing on the kibbutz river
.
I am essentially in aconstruction management role and
I've come to see my job as I amthe person who understands and
(43:11):
listens and knows enough aboutall the different specific
things that other people careabout.
So we, you know, we have aspecific person whose job is to
come in and care about erosionand sediment control, and
someone else you know, or adepartment or a regulator, who
cares about fish habitat, andthen we've got the revich guys
telling me what they can do andthey can't do and what's easy
and what's hard and same for theconstruction guys, and you've
(43:33):
got the project manager withtheir budgets and time frames.
All of these different anglesof you know very specific
perspectives that have specificrequirements and things they
care about, and inevitably thoseare not going to all line up
and it's my job to notice whenthey're not lining up and then
(43:54):
kind of broker the compromise.
Dr. Siwan Lovett (43:56):
That's lovely hearing you describe it and your
eyes light up as you're doingit.
So, yes, project management canbe very exciting folks.
So as we come to the end of ourtalk today, I want to ask you
whether you have a favouriteriver or body of water.
These are questions that we askeverybody on our show.
Margie Dickson (44:15):
Oh, can I give you two?
Dr. Siwan Lovett (44:17):
Okay.
Margie Dickson (44:23):
In South East Queensland.
I think a really special riverfor me is the Cullula River.
So it's right up the top ofSouth East Queensland and most
of it flows through this teatree country and then it winds
its way out through a series oflakes to the sea at Noosa.
But because it flows throughthat tea tree country it's red,
it's stained with the tanninsand when you kayak up it and you
(44:45):
look through the edge of theriver it's sort of yellowy where
it's shallow and then changesto this almost wine dark reddish
colour.
That's just bizarre andincredible.
And it's also drinkable.
You know it feels reallystrange.
You go on a kayak expeditionand you're drinking this river
but it doesn't look like whatyou would expect a river to be.
(45:09):
And if you're up really earlypaddling up that river it almost
looks black when it's reallydeep, like a black mirror, and
then your kayak is kind ofputting the first ripples on it
in the morning.
Dr. Siwan Lovett (45:23):
Well, that sounds amazing.
You need to send us a photo.
Okay, so that's that one.
Which is the other one?
Margie Dickson (45:31):
And another place that's really special to
me is Mount Barney Creek.
So it's down at the other endof southeast Queensland and you
know, here winter is our dryseason and then the rain comes
in summer, and so there'll bethis time often where it's
heated up, it's getting, youknow, almost too hot to be
(45:51):
bushwalking and to go out intothe playground.
That is sort of the naturalareas of southeast Queensland
For me.
You're looking for the waterand sometimes you're waiting for
the water to come because thelittle creeks are sort of dry or
a bit stagnant and not thatinviting.
And Mount Barney Creek is onethat sort of flows strong and
(46:14):
clear and cold through the wholeyear, and so it's one of the
first places that you can go toas kind of the season's
transitioning from the drywinter, warming up and still
waiting for the summer rain toarrive.
And it again flows through abig section of National Park
that we have.
So it's a place that you canwalk off track and you can, you
(46:37):
know, be part of this wild,rough country.
The creek itself is full of biggranite boulders that you kind
of rock hop along, and it sitsunder not quite the highest but
certainly the most imposingmountain in southeast Queensland
, so it makes you feel, I guess,small and a little bit
(46:59):
awe-inspired.
We're all about the awe.
Dr. Siwan Lovett (47:03):
Margie Awe is very important.
But, I think you should get ajob with Queensland Tourism,
because I now want to go to boththose places.
Don't come in summer.
Margie Dickson (47:15):
No, I'm not in summer, don't you worry it won't
be in summer.
Dr. Siwan Lovett (47:17):
It's the reason I live in Canberra.
Where do you feel mostconnected to country and to
nature?
It sounds like these places arepretty important, but they may
be somewhere else.
Where's that connection comethrough for you?
Margie Dickson (47:30):
For me it is about the off-track adventures,
so it's not so much one place,it's about having built a
picture in my head, I guess, ofthe wider landscape that is sort
of my playground and my place.
I was a scout for 20 years sowe went on a lot of sort of
(47:50):
local expeditions in that timeand, yeah, being able to move
through off-track country andsort of know where the water is
and have an expectation of whenit'll be there and looking at
the landscape changing as I walkthrough it is definitely
(48:12):
something that makes me feel,yeah, connected to this place
that I'm in and competent, Iguess, to to be there yeah, that
confidence to walk throughthose environments is actually
really important, because manypeople don't have that
confidence um, so I think it'sactually a really fantastic
(48:32):
attribute to have and it'ssomething that I feel strongly.
If I'm traveling like, I'm quiteaware that I, you know, I don't
know how an alpine environmentworks, I wouldn't know what to
expect the weather to do uh, Ireally enjoyed, uh, a long hike
up in the northern territory.
(48:53):
It's one of those kind of famousbookable ones called the jack
bulla, but we did it right atthe end of the season, when
you're allowed to go before theysay okay, that's it, you're
going to be fried to a littlecrisp chip, go away till next
year.
So it's about 40 degrees duringthe day, but you, just you have
to adapt yourself to thelandscape and so that walk each
(49:15):
day is pretty short.
So you get up really early, youdo your 7 or 8 or 10 Ks, you
get to your next camp by 10 amand all of the camps are by this
beautiful, amazing water and Iwas just amazed by how much
water was there even right atthe end of the dry season and
then you spend your whole dayliterally in the creek like a
(49:36):
little crocodile and it'sexcellent.
But it is such a differentpattern of the landscape and you
have to adapt yourself to that,and I think that's something
that I kind of look for andappreciate.
Dr. Siwan Lovett (49:53):
That's wonderful.
So what drives you to do whatyou do and what I hope you're
going to continue to do, becauseyou're obviously a?
I hope you're going to continueto do because you're obviously
a major asset for Healthy Landand Water.
I would suggest.
Margie Dickson (50:05):
I never really knew what I wanted to do as a
career.
I hated that question.
You know people ask you all thetime when you're at school, at
uni, and every time I thoughtI'd made a decision it turned
out there were still options.
But I kind of thought to myselfwell, if I don't know what I
want to do, I like at the veryleast I'd better make sure it's
(50:26):
something useful.
And this definitely feelsuseful.
You know I picked engineeringbecause it is a fundamentally
useful profession in that itexists to make decisions and
solve problems and answerquestions that you know someone
has brought to the table.
Um, and so I'm getting to dothat.
(50:49):
You know, for our rivers and forour landscape and for, you know
, some of our agriculturallandholders out there who don't
have a heck of a lot of othersupport.
You know they're a long wayfrom the urban areas and so it.
You know I am small, we are allsmall compared to the.
You know the forces of natureand the, the scale of what's
(51:15):
going on in our landscapes, butI guess, at the scale that I can
work, I think it's worth doing.
Dr. Siwan Lovett (51:23):
Fantastic.
Thank you.
I think that sentiment isshared by many of us.
I often think to myself youknow, a 100 year plan for a
river is a much more realistictime frame, so I can do my bit
and then pass it on to the nextperson, hopefully a little
better than it was before.
It's been such a pleasuretalking to you today, Margie.
(51:45):
Thank you so much for coming onthe show.
Thank you, it's been lovely tohave a chat with you.
Great.
Until next time, listeners.
Bye.
For now you can subscribe toTake Me to the River wherever
you get your podcasts.
Visit arrc.
au forward slash podcast tolearn more.
(52:07):
That's arrc.
au forward slash podcast.
We acknowledge and respectAboriginal and Torres Strait
Islander peoples as thetraditional and continuing
custodians of the country andthe rivers on which we live,
learn, love and play.
We respect and learn fromElders, past, present and
emerging, valuing theirknowledge, insights, cultures
(52:30):
and connections to the waterwayswe all love and care for.
I'm always looking at the area and thinking
, okay, where does the energy go, where's the energy coming from
and where's the energy going?
Because that's what erosion isessentially it's when you've got
a certain amount of energycoming down the river, in the
water and it's got to gosomewhere.
And erosion happens when thatbalance is off and there's more
(00:21):
energy than the bed and thebanks of the river can handle,
and so then the river justshoots into them.
Dr. Siwan Lovett (00:45):
Hello and welcome to Take Me to the River,
sharing stories and inspiringhope with extraordinary people
who care for our rivers.
I'm your host, Dr Siwan Lovett.
Today I'm joined by MargieDickson , Environmental Project
Manager at Healthy Land andWater.
Margie is a civil andenvironmental engineer with a
passion for protecting andregenerating southeast
Queensland's waterways.
(01:06):
She works on deliveringon-ground projects that
stabilise riverbanks, reducesediment and nutrient runoff and
support healthier ecosystemsand communities.
Margie is currently leading aninnovative project on the
Caboolture River whichre-establishes mangroves for
long-term bank stabilisation andecosystem resilience.
This effort combines herengineering expertise with
(01:30):
nature-based solutions,including the use of hardwood
logs and strategic earthworks tocombat erosion.
The project is not onlyaddressing critical
environmental risks like acidsulphate soils, but also
exploring how nature-basedsolutions can serve as
alternatives to traditional hardengineering approaches,
increasing climate resilienceand creating fish habitat.
(01:53):
Hi, Margie, it's wonderful tobe talking to you today and I
know we're going to be coveringa lot of topics, but what I
first wanted to start with was Iunderstand you have a civil
engineering degree.
How have you ended up inriparian restoration and
conservation?
What's that journey been?
Margie Dickson (02:11):
A little bit of luck and a lot about sort of
community and connections andthe networks you didn't know
were professional, I think.
So I spent my first four yearsout of uni with a civil
engineering consulting firm,which is where a lot of
engineering graduates go, and Iwas in a team that was actually
all about trying to getrecycling infrastructure built,
(02:32):
which is super important, and itwas a really good team.
But, oh my God, biginfrastructure is slow and I
don't think any of the bigprojects I worked on in my first
four years out of uni haveactually broken ground yet.
So yeah, I was just starting toget a little bit impatient and
I kind of thought maybe I'd liketo work on something a bit
smaller and kick some dirt andlook some people in the eyes and
(02:55):
see some things finished.
And I don't think if I'd justbeen looking around on the
internet I necessarily wouldhave picked this job or thought
I could do this job.
But it was actually my oldscout leader who reached out to
me and said hey, you know, thecompany I work for has a team
looking for good people.
I think you're good people.
You should give this a crack,and it was so important, I think
(03:20):
, to have that little nudge ofsomeone who knows you just
enough to give you a bit ofencouragement, a bit of a push.
And I, you know, because hepersonally asked me I read the
advert twice and I thought longenough to go okay, I don't do
that, I don't know some of thosethings yet, but wow, I would
really like to.
That sounds awesome.
Yeah, so I started this job verymuch on the basis that, well, I
(03:45):
started this job saying not,you know, I can do everything in
this list, hire me and I'll beup and running from day one.
It was a I learn fast.
If that's what you're lookingfor right now, maybe I'm the
person for your team.
And it's been so much learningin the last sort of two and a
half years at Healthy Land andWater.
So Healthy Land and Water isthe natural resource management
(04:07):
group for southeast Queensland,so we're involved in all sorts
of things in waterways, ingrazing, best practice, in
helping people in thehorticulture sector, wildlife,
coastal areas, but my teammainly works on restoring
waterways and so that's a mix of, you know, bank stabilisation,
(04:30):
things with earth movers and youknow a bit of an engineering
component.
But also vegetation is alwaysreally important and the
biodiversity side of things, andthat's really been something
that I've learned on the job,which has been excellent.
I've really enjoyed thatjourney so far.
Dr. Siwan Lovett (04:45):
That's just a great story.
It's interesting.
You know, I always say topeople that your networks are
gold, and there's so many peoplethat I've talked to who have
ended up in river management orworking with communities.
That was as a result of someonerecommending them, and I just
think we need to invest in whatI call social capital.
(05:07):
So that's the networks andrelationships, and actually last
week I was at a conferencewhere I gave a talk talking
about how powerful they are, soHealthy Land and Water.
Then you're now working in andyou're out on rivers.
How are you applying your civilengineering training to working
on rivers?
Margie Dickson (05:24):
Can I just have a comment before I answer that?
Yeah, I think I'd really agreeabout the networks, and
something that I tell peopleoften is it's not just the
networks that are kind of in theroom with the glass of bubbles,
wearing the nice networkingclothes and I think that was
what you saw and heard about andgot pushed towards a lot at
(05:47):
university but the networks thatare actually just in the rest
of your life and you know,bringing your whole self to you
know, whatever it is that you'reinterested in, it's still worth
putting time into those andsurprisingly often there are
intersections with you.
You know that journey throughyour professional life.
At least that's definitely beenmy experience over the years.
Dr. Siwan Lovett (06:10):
I love that reflection because I think
you're right.
Often at uni it's presented asyou need to network, you know
when you're in a meeting or youneed to go to this or that, but
in actual fact it's theday-to-day investment that you
make in relationships and takingup opportunities that really,
in your case, has come throughin terms of you know, a scout
(06:34):
leader, I mean, who knew that'sfantastic.
So over the last couple ofyears you've been having a
really intensive course on howrivers work and they move and
you know they cut new pathsthrough areas that sometimes
people don't want them to, or wetake away the vegetation, which
is sort of our naturalengineering.
What have you been reallynoticing about the rivers of
your region and what are some ofthe biggest issues that you're
(06:55):
facing in southeast Queensland?
Margie Dickson (06:57):
Well, I think, as you said, vegetation is
always the long term strategyfor keeping our rivers stable
and keeping them healthy.
But where that vegetation hasbeen lost or removed over the
years, it can be quite achallenge to get it back.
And that's kind of where theengineering component of river
restoration comes in.
It's never your long-termsolution.
(07:21):
You know, we're not trying toturn our rivers into a fixed
concrete structure, butsometimes you need some level of
engineering and design tocreate stability for long enough
for the vegetation to getestablished well enough that
it's then doing that job.
And yeah, learning to look atrivers, understand how they work
, to kind of think like a rivera little bit, has been a really
(07:44):
interesting journey.
And I mean the people whospecialize in that, they're the
geomorphologists.
But I get to spend a fair bitof time either walking the river
with those guys or looking atthe designs they've suggested
and talking that back and forth.
You know, does that make sense?
Can we build it?
And I guess the way somethingthat probably has come from my
(08:06):
civil engineering training andway of thinking is I very often
look at, you know, erosionissues that we're trying to
decide if we should do anything,if we can do anything, how to
fix them.
And I'm always looking at thearea and thinking, okay, where
does the energy go?
Where's the energy coming from?
Go where's the energy comingfrom and where's the energy
(08:27):
going?
Because that's what erosion isessentially it's when you've got
, you know, a certain amount ofenergy coming down the river, in
the water, and it's got to gosomewhere.
And there are lots of places itcan go.
It can pick up the rocks andthe gravel in the bottom of the
river and move them along for abit until it, you know, slows
down and drops them out, or itcan go into the bed and into the
(08:47):
banks.
And if the bed and the banks ofriver can handle that flow
because it's a rocky gorge orit's a really dense forest, then
that's fine, that's, that's agood way of taking energy out of
the water.
And erosion happens when, whenthat that balance is off and
there's more energy than the bedand the banks of the river can
handle, and so then the riverjust chews into them, and that's
(09:10):
essentially what erosion is.
And so then, when we're talkingabout solving it, we're going
okay, how can we get that backin balance?
And there's a few different.
You know parts of the equation,I guess, and you're looking at
what can I influence here, whichone can I change to get that
balance back?
Dr. Siwan Lovett (09:30):
That's a really great description and I
think for people that don'tunderstand rivers, you know it
can be really frightening whenthey're flooding and it can be
really frightening when they seeerosion, but often our reaction
in terms of fixing it is tomove that water even faster away
from our area, whereas a lot ofthe sort of nature-based
(09:51):
solutions that we're looking atslow the water down.
Is that the sort of work thatyou've been doing?
And I understand you've got aproject on the Caboolture River
at the moment.
Can you tell us a bit moreabout that?
Margie Dickson (10:02):
Yeah, absolutely so.
Our project on the CabooltureRiver is nine sites that we've
been working through over abouttwo years.
They're all bank stabilisationof sections of the banks that
were kind of vertical erodingcliffs, and it's come about.
It's funded by the local waterutility because when that dirt
(10:25):
falls out of the side of theriver and into the water it's
got nutrients in it.
It's got nitrogen andphosphorus and the water utility
has regulations around thosenutrients in the river.
And fixing the bank erosion isone of the things that they can
do to help meet the obligationsthat they've got around keeping
the river healthy, to help meet,you know, the obligations that
(10:46):
they've got around keeping theriver healthy.
Most of our sites are down inthe lower part of the river.
So the estuary yeah, thatlandscape is a big flat
floodplain and you can see theriver meandering out through it.
You've got Melaleuca forests orpaddocks or housing
(11:07):
developments in some spots onthe flood plain and then the
river itself is fringed withmangroves and as you get closer
and closer to the bay, thosemangroves and salt marsh take up
more of the the land on eitherside of the river and even while
we're working there is thisbeautiful dense mangrove fringe
along the lot of the river, butthen in some spots that's been
lost and it just hasn't beenable to restore itself Every
(11:31):
year.
The other parts of the riverthat have lots of mangroves they
fruit and there's heaps ofpropagules floating around.
You'll see them sprout up theirfirst two little leaves as well
.
Dr. Siwan Lovett (11:41):
But you know, it's an urban area.
Margie Dickson (11:43):
We've got recreational fishing, we've got
boats going through and eventhat boat wash from fairly small
powered boats kind of is enoughto be a problem for the little
baby mangroves and it's enoughto nibble away at the.
The base of the vertical cliffis, which is what the banks have
now become in the spots thatwe're fixing, and so the so the
(12:05):
bottom of the bank gets nibbledaway and the top of the bank
falls in and then those littlebaby mangroves have gone and
they just don't have the time toget up and sort of be holding
the bank together and beprotecting the bank from that
wave energy.
If they got big they'd be doinga great job, like sections of
the river 100 metres further up.
But it's really hard for natureto re-establish on its own and
(12:29):
I guess that's where thisproject comes in.
So it has a first stage that issome pretty serious looking
construction.
We're reshaping the banks andthat is all about creating a
stable area for then theriparian vegetation to be able
to re-establish, and there'ssort of a flat protected section
at a good elevation formangroves and then a gentle
(12:51):
slope coming back up.
That's got different speciestransitioning from sort of more
salt-loving ones down at thebottom to your kind of overbank,
your eucalypts and othercoastal vegetation up above the
tide level.
Dr. Siwan Lovett (13:07):
It sounds amazing.
It must be a little hazardousat times, because Caboolture is
quite a big river, especiallyout, you know, when you're
getting down toward theestuarine areas.
What sort of people have yougot working with you?
Are you getting, you know,barges with machine on them, or
are you able to do most of itfrom the bank itself?
Margie Dickson (13:24):
Yeah, no.
So are you able to do most ofit from the bank itself?
Yeah, no.
So we're able to work from thetop of the bank and we're
working with an earth mover thatwe've been working with for a
long time.
They've been doing thisrestoration work with Healthy
Land and Water for much longerthan I have and, yeah, this is
their bread and butter.
It can be tricky, but it'ssomething that they've learned
(13:45):
and they know how to do.
Dr. Siwan Lovett (13:47):
So it's a fairly major intervention.
You know, I know for a lot ofour restoration projects you try
and minimise that level ofintervention, but it sounds like
with a cliff that that'svertical and I'm sure people can
think of cliffs that they'veseen you actually need to do
this reforming in a way.
What's the reaction been withlocal community?
(14:10):
Because I'm assuming that thiswork's being done on private
property.
Margie Dickson (14:13):
Most of this work is being done on private
property.
I think there's one site that'sowned by the council.
I'm actually not aware of anyparticular reaction or even
strong opinions from the localcommunity at this stage, other
than sort of one day whensomeone fishing in their tinny
stopped by to say, hey, what areyou doing here?
This looks a bit serious.
(14:35):
But when you're able to explainthat what you're doing is
joining up the gap in themangroves and the whole purpose
of it is to make the river alittle bit cleaner and make a
little bit more fish habitat inamong those mangroves when they
get up, I think people aregenerally pretty comfortable
with that.
Dr. Siwan Lovett (14:54):
Great and, from the perspective of the
private landowner, somelandowners are more difficult to
work with than others.
Is your sense that for theselandowners, they're seeing these
cliffs as problematic I mean,it is their land disappearing
and that they're comfortablewith the ongoing management of
those areas?
I'm assuming that they willneed to fence out their stock
(15:16):
from the area that you'rerevegetating.
Is that the case?
Margie Dickson (15:20):
Yeah, so it's true that when you're trying to
fix, you know, an issue of theriver taking land in a kind of
uncontrolled way, you do need todeliberately take some land out
of production for grazing, andso in this case, it's about
three times the height of thebank, plus a bit more for trees
on top of the bank.
(15:40):
And, yes, we're putting inpermanent fencing around that
and there's some ongoingmaintenance as part of the bank,
and, yes, we're putting inpermanent fencing around that
and there's some ongoingmaintenance as part of the
project as well.
Dr. Siwan Lovett (15:49):
So what would have caused those cliffs
originally?
Like you're putting vegetationback, is the assumption right
that it's been taking thevegetation away that's actually
caused the problem?
Margie Dickson (16:00):
So I think definitely sort of historically
taking away the vegetation isabsolutely part of what's caused
the issue in these spots.
They're also mostly on theoutside bend in rivers, so
that's a spot where the energyof the river moving past is
highest, and so perhaps that'seither why the issue started or
(16:24):
part of the reason why it hasn'tbeen able to heal itself over
time and again.
That's, I guess, why there is abit of a heavier engineering
component in these spots.
Dr. Siwan Lovett (16:35):
And so, in addition to the sort of grading
the bank, are you putting anystructures in?
I know that wood or groins aresometimes used.
Is that happening here as well?
Margie Dickson (16:45):
Yeah, so down on that flat area in the tidal
zone where we're trying torecreate the mangrove forest.
We definitely needed a littlebit more protection for those
baby mangroves as they'regetting up, so that they're able
to be sort of sheltered fromthe boat wash that's coming past
for three or five or six yearsuntil they're big enough to then
(17:08):
be really protecting themselves.
And so we've got an arrangementof hardwood logs pinned into
that flat section and those arebreaking up any boat wash.
That's sort of hitting the bankand it's creating, yeah,
stiller zones, sheltered zones.
Dr. Siwan Lovett (17:26):
And so that's really to protect them so that
they can re-establish.
I'm assuming that are youpicking up fruit from the
mangroves on either side ofthese areas, or are you actually
propagating mangroves that getby a supplier to pop them in?
Margie Dickson (17:39):
Yeah, so that's an interesting one.
On the first the sites thatwe've been through so far, we
have been deliberately placingmangrove propagules on the bench
.
We couldn't actually collectthem from the Caboolture River
because the Caboolture River,where we're working, is
classified as fish habitat A andall mangroves are protected
(18:01):
marine plants.
So it's actually quite heavilyregulated.
What you own aren't allowed todo, so we had to go and get them
from the next river south.
And then there's regulations on.
The regulations for collectingmangroves are different to the
ones for propagating them, so weweren't allowed to propagate
the seeds.
It meant it had to be a sort ofone day at a time strike
mission where you head down tothe pine river and you collect
(18:23):
your buckets full of propagulesand then you trundle back up to
the kubilcha river and you popthem in the ground on the same
day.
Um, which has been a it worked.
It's been a little bit of aninteresting logistical exercise,
but natural recruitment ofmangroves is far and away
bringing in more new little babyseedlings to these sites than
(18:45):
anything that we've planted.
And so for next year's sites,or perhaps the next round of a
similar project, we wouldprobably strongly suggest that
collecting and planting mangroveseeds isn't really necessary if
you've got established bits ofmangrove forest fairly nearby.
(19:05):
We sometimes talk about mangroveseeds.
If you talk to a botanist theywon't say that they actually
call them propagules, becausewhat mangroves make are, I guess
, a little bit more developedthan seeds.
They tend to be quite large,there's a lot of stored energy
in there, they float and they'rereally almost ready to grow.
So we have two main types ofmangroves on the river where
(19:30):
we're working, and one of themmakes propagules that are kind
of roundish, a bit like a reallybig thick 50-cent piece, and
then some of them makepropagules that are more like a
skinny version of your pinkyfinger perhaps, and they all
(19:51):
float.
And so the mangroves, yeah,come into a fruiting season all
together and you'll have thisbig mass fruiting event and lots
of these mangrove propagulessort of bobbing on the tide up
and down the river.
And if they happen to settle ina little spot that's, you know,
at the top of the tide and it'ssheltered enough that the
water's slowed down and themangrove propagules got stuck
(20:13):
perhaps it got stuck behind alog that we pinned on the bench
to help it out then it'll liethere for a bit and it'll pop
down roots into the mud and thatpropagule will crack open and
reveal those first two leaves,and so it turns from this little
floating life raft into a tree.
Dr. Siwan Lovett (20:34):
Amazing.
So have you studied thestructure of mangroves?
I was just wondering about this, because when I see them, it's
like they don't have one stem.
You can see their roots, reallycan't you?
And then they grow up and it'sthey're like I liken them to
making little chambers, or likelittle chapels, almost where, um
(20:57):
, you know, little fish live anda whole range of other things
can can use them as a support.
Um, what have you learned aboutmangroves that you didn't know
before?
Obviously, you're now an experton propagules and I'll never
use the word seed again.
Margie Dickson (21:10):
Oh, I certainly wouldn't say I'm an expert.
I haven't studied mangroves,but I guess, as part of learning
on the job, suddenly I'm payingattention to them in a way that
I wasn't before.
Yeah, when I'm looking at thelandscape that I might be trying
to repair or I'm monitoring,you know our sites after
completion and the differentspecies of mangroves grow really
(21:31):
differently.
You know, one of the species inthis area does have those
unusual roots that you weredescribing, where, yeah, the one
single stem of the tree seemsto start a little bit in the air
and then we've got all thesekind of roots like some kind of
strange tripod reaching downinto the mud.
Others are much more like treeswith one stem coming out of the
(21:54):
ground, but then they'll besurrounded by this bed of little
hard pointy roots poking up outof the mud, and those are
called pneumatophores and theyhelp the mangrove to breathe.
Dr. Siwan Lovett (22:06):
Wow, that's great.
Thank you for explaining thatbecause, as you were saying, I
was thinking about thosesticking up.
They don't look like fun placesto walk through.
Have you been having a bit ofexperience in and amongst the
mangroves?
Margie Dickson (22:21):
Well, yeah, I also try not to walk on those
because they crunch under yourfeet and you feel a bit guilty
about, you know, repairingmangroves over here and stomping
on their, their roots oversomewhere else.
So, um, there's some spots onthe river where we can do the
monitoring by kayak, and ifyou've got a mature mangrove
forest that's already got a bigpneumatophore bed, you know the
(22:44):
best thing to do is not disturbit.
We're not generally needing toget in there, and so I'm mainly
walking on the the muddy bits ofback that don't have mangroves
and trying to figure out why, ortrying to figure out if our
site is helping to bring thoseback.
And then by the time it is anice, established, dense,
difficult to walk through forest.
(23:05):
We're pretty happy to leave italone to do its thing.
Dr. Siwan Lovett (23:08):
You've done your job, then.
What are some of the creaturesthat you've noticed in amongst
the mangroves, that you mightnot have been expecting to see?
Margie Dickson (23:17):
Ooh, we've seen a stingray in the Caboolture
River, which was a little bitunexpected, and a shark.
We have bull sharks in sort ofthe Brisbane River, the
Caboolture River.
Dr. Siwan Lovett (23:31):
We know they're there.
Margie Dickson (23:32):
But it did swim past just on the day that we
were about to kick off the site,you know, walking over, scoping
everything out, writing up thesafety induction, and went we
better put no swimming.
Hey, we'll just add that as asite rule.
Dr. Siwan Lovett (23:45):
And then the sharks went past.
Oh my goodness, that sounds abit scary.
What about in amongst thecanopy?
Are they really importantplaces for birds?
Margie Dickson (23:54):
Yes, mangrove forests are definitely really
important ecosystems on ourcoast.
It's often, you know, quitehard to observe the wildlife
that lives there because it'sreally hard to move through that
ecosystem.
It's not human friendly butit's excellent as a nursery for
the little fish.
It's a protected spot for themto to breed and to grow up.
(24:16):
It's really good for birds.
They're able to move throughthat landscape and then they're
looking for those little fish.
It's absolutely full of littlecrabs.
Um, and I learned recently thisis not on the Caboolture River,
but I learned recently thatwe've also got an endangered
water mouse that livesexclusively in mangrove forests
(24:36):
and builds little nests made outof sticks in among the
mangroves.
That's not one of my projects,but I work on another wetland up
the top of the Sunshine Coastand I was arriving there one day
to do my water qualitymonitoring and ran into someone
from the University of theSunshine Coast, all dressed up,
looking very practical.
I was like, oh, what are youoff to do?
(24:58):
I'm off to check my trap linesand my cameras to see if we can
find endangered water mice inthe conservation park next door.
And he thought he had foundthem, which was really exciting
because that's an area that isvery low-lying um parts.
Large parts of it havehistorically been cleared for
cane, but the sugar cane mill inthat area closed over a decade
(25:21):
ago and some of those cane areasyou know will be underwater
with sea level rise in mylifetime and so there kind of is
planning and work and thebeginnings of a transition, I
guess, for that area underway.
My work's part of that.
The Sunshine Coast Council'salso doing a lot of work in that
(25:43):
space.
For them they're looking atmangrove forests as carbon
offsets and that's why they'relooking for the endangered water
mice in the bits of forest thatare already there, because if
they're there it means that asthe new areas that are being
managed to transition to a newmangrove forest, that'll
actually be expanding thehabitat for these sort of
(26:06):
secretive little critters.
Dr. Siwan Lovett (26:08):
That's a wonderful story.
I didn't know that there was awater mouse, so we have our
rakali, which we really love,which you know we're often
called the water rat.
Margie Dickson (26:15):
but rakali seems to be.
I've just been to.
Dr. Siwan Lovett (26:17):
Rakali as well .
Yeah, yeah, oh, that's good.
Yeah, rakali does seem to becatching on.
I think it's really fantasticthat we're talking more about
the benefits of these areas,particularly.
You know you were mentioningabout sea level rise.
You know climate change is realand the thermal refugia that
areas like thick mangrovesprovide is going to be essential
(26:40):
, not just for critters but alsofor humans too, because it
actually creates a microclimate.
Have you done any work on that?
Has the Healthy Land and Waterlooked at that at all?
In terms of the climatevariability benefits of
mangroves?
I don't think we have.
Yeah, I was wondering with theoffsets, because we're looking
at trying to develop a tool forbeing able to assess sort of the
(27:04):
carbon sequestration benefitsof riparian areas.
We know that they're betterthan most areas because they've
also got the blue carbon and thegreen carbon.
Yeah, so we're also looking atthat.
Tell me a bit more about theother sort of work that you're
doing.
I know that you've got aninterest in acid sulphate soils.
How do they come about and whatsort of work are you doing in
(27:27):
that area?
Margie Dickson (27:29):
Well, the acid sulphate soil management was a
learning curve on the Caboolturejob, simply because it was
there and we had to make surethat we were managing them sort
of safely.
So what acid sulphate soils areis they're a legacy from the
distant past when the sea levelswere different and large parts
(27:49):
of our coast actually wereunderwater, and so they formed
in these hot, shallow seas.
And it's chemistry I am not achemist, but there's chemistry
locked up in those soils that ifthey're just buried, you know,
in layers under the ground, it'sfine, that's all good,
(28:10):
everything's stable, theenvironment on top's happily
ticking along.
But if you expose these soilsto air, they start reacting and
they generate really strong acidand that can then leak out into
groundwater or adjacentwaterways and quite dramatically
change the pH and make it quitehostile for all sorts of life.
(28:32):
So if there are acid sulphatesoils in the landscape where
you're working and they're mostcommon, yeah, along the coast,
sort of less than five metresbelow sea level you've got to be
really careful.
You've got to definitely checkbeforehand and if you think
you'll be disturbing acidsulfate soils, you definitely
(28:53):
need to have a plan so they areregulated um and some of the
sites on the Caboolture River,part of what we were excavating
had an acid sulfate soil risk.
Um, I think, to be honest, oneof the best outcomes that we've
had in terms of small designchanges during the project is we
(29:14):
were able to make some littleadjustments to where that flat
section for the mangroves wassitting, in terms of elevation,
to make sure we didn't disturbthe really nasty acid sulphate
soil, disturb the really nastyacid sulfate soil.
So on, you know, our first bigsite, the, the bank was about
(29:34):
three meters high, so you've gota little bit of top soil at the
top, and then you've got, youknow, ordinary, non-acidic, you
know paddock, and then belowthat there was some soil that
you know showed up as, yeah,this triggers the thresholds for
being acid sulfate, so you'regoing to need to manage it.
But in terms of treatingtreating acid sulfate, so you're
mixing it with something that'sgoing to neutralize that
(29:55):
acidity.
So in this case it wasagricultural lime, and so we had
our soil tests and they said,yeah, this stuff on top, like
it's a little bit, you'll needto mix it with six kilos of
agricultural lime per cubicmetre of dirt.
And then the soil tests go downa bit further and they go ooh.
And then there's this estuarinemud layer and in that layer if
(30:16):
you want to treat it, you'regoing to have to mix it with 100
kilos of agricultural lime percubic metre of dirt.
And that's a lot.
You know it's a lot of stuff tocut in.
It's a lot of stuff to cut in.
It's a lot of stuff to mixthrough it's.
You're just playing with muchnastier material and the option
should always be, you know,whether you're doing restoration
(30:37):
work, whether you're doing ahousing development, whether
you're doing infrastructure, ifyou've got acid sulfate soils,
you should be looking at themand going?
can I work around this?
Can I actually not expose thisto the air?
And so we looked at themangrove forests that we had
upstream and downstream of oursite and we went.
Well, you know our design isone line on the plan.
(31:00):
You know our flat bit for themangroves will be at 0.7 metres
above sea level.
That's where we'll put it.
But when we sort of looked inthe environment where we were
working, we went.
Well, the main species here it'sactually able to grow and
thrive across a wider tidalrange than that, so it can
(31:21):
handle being wetter and it canhandle being less wet.
So for the one sort of, it wasjust the top end of our site
that was showing up theacesulfate risk.
We went I think we can raisethe bench so we just don't dig
as deep.
We don't dig up that reallynasty 100 kilos of lime per
cubic meter reactive acidic soiland we can be confident that
(31:45):
ecologically and functionallythe project's still going to
work.
And so we were able to makethat adjustment.
I think that was a much betteroutcome for the project and for
the environment than you know melearning to treat and manage
and test acid sulfate soils,which I've done for the lower
risk stuff.
Dr. Siwan Lovett (32:05):
I think so, definitely it, you know.
As you're talking about it,though, I'm thinking about the
enormity of this for alandholder who might not be
anticipating that they've gotacid sulphate soils.
I think our knowledge hasincreased so much more now You'd
kind of hope that landholderswould get soil samples done so
that they understand.
You know, what the implicationsare of liberating that material
(32:28):
.
Does it tend to be in sort of aclump, or is it sort of a quite
distinct line in terms of thelayers of soil as you go down?
Margie Dickson (32:39):
It's more like a layer because, like I say, it's
formed at the bottom of theseancient warm oceans.
So it's kind of like everywherethat was the bottom of the
seafloor will have thischemistry going on and sometimes
it can be quite visible in thesoil profile.
But you can't rely on visualidentification.
(33:03):
You should definitely get a test.
But the important thing is, ifyou're not digging them up, it's
actually not a problem.
So you can have theselandscapes and you can grow
crops on the top or you cangraze or you can, you know, have
a non-acidic ecosystem thereand that will tick along quite
happily and that's absolutelyfine.
You only run into issues ifyou're you know digging drainage
(33:31):
, ditches and changing thegroundwater level, or you know
doing big excavation work.
That's when you know this riskthat's been dormant actually
becomes a problem.
Dr. Siwan Lovett (33:44):
So these designs have gone in and you've
done this work.
You've had some big floods.
How are they holding up with?
Margie Dickson (33:50):
uh, with floods, oh, yeah, there was a a couple
of weeks in, uh, january 2024when I think everything I'd
worked on in my time at healthyland and water was underwater,
and that was.
I was sitting there a littlebit nervous.
They're going.
Oh my goodness, if it's all inmorton bay, I might need to have
a little cry and get anotherjob.
But no, it was okay.
It was okay.
Um we were really happy with howour first sites held up during
(34:15):
those january 2024 floods.
It was a it's an important test, um, I would definitely say.
At that point they'd beenplanted and some of the little
mangroves were up, but thevegetation wasn't doing the
heavy lifting.
It was still quite young and itwas the engineering component
of the project that did theheavy lifting in terms of how
(34:38):
those sites fared.
So reprofiling the bank andthen placing those big logs as
well was really important in, Iguess, helping to protect the
plants that were there.
It was also a flood that spilledout onto the floodplain, so it
was.
You know, our site was fullyunderwater and it was flowing
(34:59):
over the paddock on top andthat's actually a good thing in
terms of the amount of energythat the trees on the banks are
experiencing.
Again, coming back to this ideaof where does the energy go
when a flood does break out,into the floodplain, that lets
(35:20):
the energy spread out a lot andit does potentially less damage,
unless we've put importantinfrastructure like people's
homes, on that floodplain, andthen the damage is really
devastating for people.
Dr. Siwan Lovett (35:37):
Yeah, definitely.
And it never ceases to amaze me, actually, when people say I
can live on this floodplainbecause the last big flood was
100 years ago and it's a100-year flood risk and you're
sort of going, yeah, but thehundred-year flood could happen
tomorrow, like just becauseyou've started here, it's not a
hundred years from now.
(35:58):
How do you go about explainingyour sorts of work and the sort
of you know?
From what I'm hearing, it's acombination of engineering
solutions that we can do andthen nature-based solutions,
really, in that we're trying toset nature up to succeed.
How do you go about explainingyour work and why it's important
(36:18):
?
Margie Dickson (36:22):
That's a big question, isn't it?
I think it's a continuousconversation because these are
big ideas and they're trickyideas and there's always going
to be conflict between room forthe river and then room for
people.
So then, that understanding ofthis is where it floods.
(36:43):
This paddock goes underwater,that's okay, is generally a
little bit easier.
Dr. Siwan Lovett (36:49):
So, having done all this work on the
Caboolture, is it sort of a waitand see game now and you're
going back and monitoring,monitoring, what are the sites
looking like?
Are you taking photos and allthose sorts of things?
Margie Dickson (37:01):
yeah, absolutely , and that's one of the really
nice things, I guess, abouthaving done a project that, like
I said at the beginning, it'sunder a regulated framework,
it's paid for by the local waterutility.
It's part of kind of the wholesuite of things that they do to
meet their responsibilitiesaround the quality of the water
(37:22):
in the river, and so because ofthat, there's actually quite
long-term monitoring on thesesites.
Um, we'll be doing it sort offor five years and then probably
another five after that, and Ithink this whole job, one of the
things that's been excellentabout this whole job is the
ability to learn small things asyou go and then apply those.
(37:45):
So I sort of mentioned thatthere's nine sites that we've
been working on over two years.
So even in the constructionphase you go from site to site
to site and you can, you canbring learnings and sort of
improve things as you go, andit'll be the same in you know
that longer term understandinghow the sites develop and that
same water utility is atdifferent stages of developing
(38:07):
up similar projects on otherrivers up the coast, and so,
yeah, the observations of thesesites on the Caboolture River
having been built and maturingare then able to inform kind of
the design for the next rivers?
Dr. Siwan Lovett (38:22):
You know you were saying that example of,
initially you were, you know,going and almost foraging for
proper gills, but this timearound you're sort of saying
actually, no, just just letnature get on with it.
So it sounds like it's a it'scontinuing to go back.
For people living on theCaboolture River or people who
are interested, is there sort ofa site that they can go and
(38:42):
have a look at, either inreality as well as virtually
online, that they can keep up todate with what's happening?
Margie Dickson (38:49):
Yeah, absolutely so.
The first site that we did isat the end of a public park
called Heritage Park.
It's part of the North Harbourdevelopment in Burkengarry East,
but yeah, it is right on theedge of that public area.
I think a park run goes past iton Saturday mornings and it's
(39:10):
one that we did the earthworkson in the middle of last year,
and then the plants have beengrowing up and we've had two,
two really warm, wet summers, soall those trees on the top of
the bank are looking pretty lushyeah, fantastic, that's great.
Dr. Siwan Lovett (39:26):
I was always envious of the growth rates um,
in queensland because I had a.
At one stage I was managingdemonstration sites across the
country and the tasmanian oneswere very, very slow.
The veg was tiny and then I'dgo up to Innisfail and the trees
would just be, like you know,over my head and I'm just going.
Oh, this seems so unfair.
Margie Dickson (39:46):
Yeah, but then you have to do weed control
forever, because it's not justthe trees that grow, well, it's
everything.
That is a very good point.
Yeah, yes everything.
Dr. Siwan Lovett (40:04):
That is a very good point, yeah, yes, okay, do
you have um any advice forsomeone who's looking at going
into this area of work?
If it's an early career personlike yourself, what would, what
recommendations would you bemaking to them?
Margie Dickson (40:14):
I'd definitely be saying go for it.
I do love my job.
I really love the mix ofgetting out in the field and
then sort of being in the officeand planning the next projects.
There is so much that you canknow about rivers and the
ecosystems that go with them.
(40:35):
You need to be always learningand it's also okay not to know
everything.
There is so much there that itreally does take a lot of
different people bringing theirinput to be constantly improving
, kind of what we're doing atour sites, and I think that's
something to embrace rather thanbe intimidated by.
It's definitely something thatI love about my team.
(40:58):
You know we've, and my team andthe people we work with.
So we've got people who worked,you know, on the tools with
revegetation contractors,killing the weeds and planting
the plants, and then have comeacross to be planning those
projects.
We've got, you know, me and acouple of other people who had
an engineering background andthen have come into this space.
We've got people who studiedscience and ecology and then
have come into this space.
(41:18):
We've got people who studiedscience and ecology and then
have come to sort of put it onthe ground as part of the team.
And so, yeah, I think you heara lot in the corporate world
about diversity drivinginnovation and that being really
important, and sometimes itsounds a little bit buzzwordy,
but I look at my team and I lookat my projects and I look at
(41:42):
the other teams in other partsof the country also doing this
kind of work and I think youknow, in our river restoration
space it's so true and it's it'sreally genuinely happening at
that project and team level,because you can come into this
space from so many differentangles and have something to
contribute, so long as you'realso willing to learn.
Dr. Siwan Lovett (42:06):
I think that's a really great summation
because, I agree, I think it'sgot to be collaborative and the
strongest projects are ofteninterdisciplinary.
And I remember someone tellingme you know, oftentimes we have
this view that experts are sortof my way or the highway,
whereas I think it's more aboutsaying, well, I know something,
you might know something, soit's better together.
(42:28):
So it's just a.
It's a much more collaborativeway of going about doing this
work and I can see how you'vebrought in a whole range of
different elements there andit's really nice, because often
we think, oh, an engineer doesthis and a scientist does this,
but in actual fact we're allpeople and we just talk about
what we're doing.
So you know, that, that seems tobe the success here.
Margie Dickson (42:49):
That was something that I was surprised
to learn about.
You know my job as I starteddoing it in the construction
management space, like whatwe're doing on the kibbutz river
.
I am essentially in aconstruction management role and
I've come to see my job as I amthe person who understands and
(43:11):
listens and knows enough aboutall the different specific
things that other people careabout.
So we, you know, we have aspecific person whose job is to
come in and care about erosionand sediment control, and
someone else you know, or adepartment or a regulator, who
cares about fish habitat, andthen we've got the revich guys
telling me what they can do andthey can't do and what's easy
and what's hard and same for theconstruction guys, and you've
(43:33):
got the project manager withtheir budgets and time frames.
All of these different anglesof you know very specific
perspectives that have specificrequirements and things they
care about, and inevitably thoseare not going to all line up
and it's my job to notice whenthey're not lining up and then
(43:54):
kind of broker the compromise.
Dr. Siwan Lovett (43:56):
That's lovely hearing you describe it and your
eyes light up as you're doingit.
So, yes, project management canbe very exciting folks.
So as we come to the end of ourtalk today, I want to ask you
whether you have a favouriteriver or body of water.
These are questions that we askeverybody on our show.
Margie Dickson (44:15):
Oh, can I give you two?
Dr. Siwan Lovett (44:17):
Okay.
Margie Dickson (44:23):
In South East Queensland.
I think a really special riverfor me is the Cullula River.
So it's right up the top ofSouth East Queensland and most
of it flows through this teatree country and then it winds
its way out through a series oflakes to the sea at Noosa.
But because it flows throughthat tea tree country it's red,
it's stained with the tanninsand when you kayak up it and you
(44:45):
look through the edge of theriver it's sort of yellowy where
it's shallow and then changesto this almost wine dark reddish
colour.
That's just bizarre andincredible.
And it's also drinkable.
You know it feels reallystrange.
You go on a kayak expeditionand you're drinking this river
but it doesn't look like whatyou would expect a river to be.
(45:09):
And if you're up really earlypaddling up that river it almost
looks black when it's reallydeep, like a black mirror, and
then your kayak is kind ofputting the first ripples on it
in the morning.
Dr. Siwan Lovett (45:23):
Well, that sounds amazing.
You need to send us a photo.
Okay, so that's that one.
Which is the other one?
Margie Dickson (45:31):
And another place that's really special to
me is Mount Barney Creek.
So it's down at the other endof southeast Queensland and you
know, here winter is our dryseason and then the rain comes
in summer, and so there'll bethis time often where it's
heated up, it's getting, youknow, almost too hot to be
(45:51):
bushwalking and to go out intothe playground.
That is sort of the naturalareas of southeast Queensland
For me.
You're looking for the waterand sometimes you're waiting for
the water to come because thelittle creeks are sort of dry or
a bit stagnant and not thatinviting.
And Mount Barney Creek is onethat sort of flows strong and
(46:14):
clear and cold through the wholeyear, and so it's one of the
first places that you can go toas kind of the season's
transitioning from the drywinter, warming up and still
waiting for the summer rain toarrive.
And it again flows through abig section of National Park
that we have.
So it's a place that you canwalk off track and you can, you
(46:37):
know, be part of this wild,rough country.
The creek itself is full of biggranite boulders that you kind
of rock hop along, and it sitsunder not quite the highest but
certainly the most imposingmountain in southeast Queensland
, so it makes you feel, I guess,small and a little bit
(46:59):
awe-inspired.
We're all about the awe.
Dr. Siwan Lovett (47:03):
Margie Awe is very important.
But, I think you should get ajob with Queensland Tourism,
because I now want to go to boththose places.
Don't come in summer.
Margie Dickson (47:15):
No, I'm not in summer, don't you worry it won't
be in summer.
Dr. Siwan Lovett (47:17):
It's the reason I live in Canberra.
Where do you feel mostconnected to country and to
nature?
It sounds like these places arepretty important, but they may
be somewhere else.
Where's that connection comethrough for you?
Margie Dickson (47:30):
For me it is about the off-track adventures,
so it's not so much one place,it's about having built a
picture in my head, I guess, ofthe wider landscape that is sort
of my playground and my place.
I was a scout for 20 years sowe went on a lot of sort of
(47:50):
local expeditions in that timeand, yeah, being able to move
through off-track country andsort of know where the water is
and have an expectation of whenit'll be there and looking at
the landscape changing as I walkthrough it is definitely
(48:12):
something that makes me feel,yeah, connected to this place
that I'm in and competent, Iguess, to to be there yeah, that
confidence to walk throughthose environments is actually
really important, because manypeople don't have that
confidence um, so I think it'sactually a really fantastic
(48:32):
attribute to have and it'ssomething that I feel strongly.
If I'm traveling like, I'm quiteaware that I, you know, I don't
know how an alpine environmentworks, I wouldn't know what to
expect the weather to do uh, Ireally enjoyed, uh, a long hike
up in the northern territory.
(48:53):
It's one of those kind of famousbookable ones called the jack
bulla, but we did it right atthe end of the season, when
you're allowed to go before theysay okay, that's it, you're
going to be fried to a littlecrisp chip, go away till next
year.
So it's about 40 degrees duringthe day, but you, just you have
to adapt yourself to thelandscape and so that walk each
(49:15):
day is pretty short.
So you get up really early, youdo your 7 or 8 or 10 Ks, you
get to your next camp by 10 amand all of the camps are by this
beautiful, amazing water and Iwas just amazed by how much
water was there even right atthe end of the dry season and
then you spend your whole dayliterally in the creek like a
(49:36):
little crocodile and it'sexcellent.
But it is such a differentpattern of the landscape and you
have to adapt yourself to that,and I think that's something
that I kind of look for andappreciate.
Dr. Siwan Lovett (49:53):
That's wonderful.
So what drives you to do whatyou do and what I hope you're
going to continue to do, becauseyou're obviously a?
I hope you're going to continueto do because you're obviously
a major asset for Healthy Landand Water.
I would suggest.
Margie Dickson (50:05):
I never really knew what I wanted to do as a
career.
I hated that question.
You know people ask you all thetime when you're at school, at
uni, and every time I thoughtI'd made a decision it turned
out there were still options.
But I kind of thought to myselfwell, if I don't know what I
want to do, I like at the veryleast I'd better make sure it's
(50:26):
something useful.
And this definitely feelsuseful.
You know I picked engineeringbecause it is a fundamentally
useful profession in that itexists to make decisions and
solve problems and answerquestions that you know someone
has brought to the table.
Um, and so I'm getting to dothat.
(50:49):
You know, for our rivers and forour landscape and for, you know
, some of our agriculturallandholders out there who don't
have a heck of a lot of othersupport.
You know they're a long wayfrom the urban areas and so it.
You know I am small, we are allsmall compared to the.
You know the forces of natureand the, the scale of what's
(51:15):
going on in our landscapes, butI guess, at the scale that I can
work, I think it's worth doing.
Dr. Siwan Lovett (51:23):
Fantastic.
Thank you.
I think that sentiment isshared by many of us.
I often think to myself youknow, a 100 year plan for a
river is a much more realistictime frame, so I can do my bit
and then pass it on to the nextperson, hopefully a little
better than it was before.
It's been such a pleasuretalking to you today, Margie.
(51:45):
Thank you so much for coming onthe show.
Thank you, it's been lovely tohave a chat with you.
Great.
Until next time, listeners.
Bye.
For now you can subscribe toTake Me to the River wherever
you get your podcasts.
Visit arrc.
au forward slash podcast tolearn more.
(52:07):
That's arrc.
au forward slash podcast.
We acknowledge and respectAboriginal and Torres Strait
Islander peoples as thetraditional and continuing
custodians of the country andthe rivers on which we live,
learn, love and play.
We respect and learn fromElders, past, present and
emerging, valuing theirknowledge, insights, cultures
(52:30):
and connections to the waterwayswe all love and care for.
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