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Spring Edition - October 2010 140 SANTFA - The No-Till Journal Vo l 7 No 4
Water security
water security
Climate Change Champions’ is not
a label that sits comfortably with
Cleve farmers Mark and Andrea
Hannemann, who see themselves as
‘ordinary farmers’.
However, their efforts in creating an
ingenious water harvesting scheme has
seen them nationally recognised by the
Climate Change Champions program.
Mt Rough farm, in the Cleve Hills in
central Eyre Peninsula, has been in the
Hannemann family for more than 100
years. The 400mm rainfall country is
undulating, with loam over clay based
soils. Mark does most of the manual
work and agronomy while Andrea looks
after the bookwork and grain marketing
activities for the 1,600ha property.
Canola, wheat, barley and peas are
grown in rotation and sheep are run
opportunistically on the stubbles. The
property supported a self replacing
Merino flock for many years but that
made way for continuous cropping when
Mark and Andrea made the decision
to move to no-till seeding. However,
a combination of herbicide-resistant
weeds and the water scheme they have
developed have seen them move back into
sheep again.
Their move to no-till and stubble
retention reduced erosion and tractor
hours and opened the way for them to
include more break crops in the rotation.
Even though Mt Rough farm is at the
top of the catchment they found areas
of salt ground were limiting production
so they developed and implemented a
15-year Landcare revegetation plan. That
plan, part of which called for extensive
tree planting, is in its 10th year. So far
they have direct-seeded 80ha - 110kms in
linear terms - of native trees and fenced
off creek lines to allow re-establishment
of riparian vegetation and now have
a network of native habitat corridors
across the entire property. They have
also removed contours and some fences
to create larger paddocks, which has
increased seeding efficiency by reducing
over-sowing, resulting in a more stable
soil and improved soil health.
Mark sows his crops with a Horwood
Scaribar with Harrington points. He
increased row spacing from 175mm to
270mm 14 years ago. He began using
GPS guidance eight years ago, when they
bought a Hardi 5033 sprayer. They now
use GPS guidance for seeding and in their
John Deere 9770 harvester.
The Hannemanns plan to begin the
move to controlled traffic farming (CTF)
using three-metre wheel bases and 12m
Mike Roberts Communications, Research and Consulting
‘you can’t run a farm with no
water!’
A view across the new storage, without cover at this stage, to the catchment area.
Spring Edition - October 2010 141 SANTFA - The No-Till Journal Vo l 7 No 4
Water security
multiples when they replace the header
next year. A disc seeder is on the wish list
but still over the horizon.
Improved water infiltration is one of the
clear benefits of their change to no-till
and stubble retention. Previously their
steep clay country had been contoured to
direct surface run-off into 40 dams for
the stock. After 14 years of no-till that
water is now retained in the paddocks by
stubble and improved soil structure.
Soil cover and soil carbon have also
increased. The soil is more friable and
no longer seals over during wet periods.
Seedlings are protected by the standing
stubble and benefit from water collected
at the bottom of presswheel furrows.
Crop sowing and spraying now occur
at optimum times as a result of soil
improvement and no-till equipment. And
yields have increased approximately 25%
since the introduction of no-till. “Even in
poor years we have managed to produce
a crop.”
Mark says his water use efficiency has
improved and is keen to give soil moisture
probes a try after participating in one of
Greg Butler’s workshops on their use.
Water
The change to no-till and stubble
retention meant more soil moisture for
crops but less water in the dams at a time
when more was needed for spraying and
livestock. Andrea explained that the farm
lies in an area between Kimba, Cowell and
Cleve that has no access to mains water.
“We loved no-till and weren’t going to
change that because we were growing
good crops on less moisture. We didn’t
want to change our cropping system
so we had to change the way that we
collected water because it was not running
off into the dams anymore. You can’t run
a farm with no water!”
With less run-off due to the change in
tillage practices they needed cart water
for stock from a standpipe in Cleve
during dry year; a practice that was
unsustainable in terms of time, money
and transport emissions.
The Hannemanns believed their water
shortage was also due in part to the
increasing short term variability that
accompanies longer-term climate change
and if they did not address the problem
it would limit their long-term viability.
They felt they had two options. One
involved accessing SA mains water from Lining is well advanced, but there’s still some work to do.
Early in the initial earth-moving stage.
Boxing up the mouth of one of the outlets built into the new storage.
Spring Edition - October 2010 142 SANTFA - The No-Till Journal Vo l 7 No 4
Water security
about 10km away through a complex and
expensive series of arrangements with
neighbours for easements, holding tanks
and pumps. They were also aware that the
price of SA mains water would continue
to increase. The other was to design and
create their own sustainable water supply.
Research
Mark and Andrea had a look at an NRM-
funded project at Arno Bay in which
water from the roof of the the Viterra
sheds was collected in a lined dam with
a floating cover to stop evaporation.
They also examined a project at Yalanda
James where a hectare of plastic-covered
catchment was created to feed into an
existing tank with a capacity of 4.5 million
litres (4.5 megalitres).
In their travels they came upon Poldar
Rock at Wudinna where, as Andrea
explained, “in the 1920s the settlers put
a wall around the base of this huge solid
granite rock to capture the water running
off it. It was harvested into a dam and
underground tanks because they didn’t
have a tap that they could just turn on.
We’ve lost our way in self sufficiency
because we have become reliant on mains
water. We need now to explore efficient
systems to complement the changing
climate and become more focused on self
reliance for our own water requirements.”
They decided to combine the concepts of
the Arno Bay and Yalanda James projects
and planned a system to try on their
own farm.
Structure
The result is a 4,100 square metre lined
catchment feeding a lined 1.3 million
litre dam with a floating cover. The dam
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Ready and waiting. With the lining completed, rain was the only thing missing
Tyres help stabilise the plastic surface on the catchment area.
Spring Edition - October 2010 143 SANTFA - The No-Till Journal Vo l 7 No 4
Water security
is 380m above sea level and the house,
about five kilometres away, is 320m above
sea level. The elevation of the dam – 60m
above the house - allows the water to be
gravity-fed through a pipeline system to
the house and stock troughs.
The dam and reticulation system is
already in use and has supplied more
than 100,000L of water for Mark’s crop
spraying this season. “Last year we ran
out of water from the shed tanks during
seeding so every morning I’d get up at
5:30am, drive to Cleve, get a load of
water, come home, spray it out during
the day and at night I’d go and get
another one. “
The lined dam and catchment produce
high-quality water. The plastic eliminates
clay particles and has a collection
efficiency of 98% so even a heavy
dew will run water into the dam. The
opaque floating cover, which will be
installed when the dam fills this winter,
will prevent algae growth and limit
evaporation. The dam is 3m deep and if
full would lose more than 2m (70% of
the total volume) in evaporation over a 12
month period without the cover. “The
plastic has a life of about 25 years so we
call it our 25 year water security plan for
the property,” Mark said.
The dam has the capacity to supply the
whole property because of its efficiencies
and because it’s hooked up to small
troughs that minimise evaporation.
Troughs are only filled when stock
are present.
Mark and Andrea estimated their
maximum water use at around a million
litres a year. Each square metre of
catchment collects a litre of water for
each millimetre of rain. Rainfall of
400mm over the 4,100 square metres
of catchment would provide 1.64 million
litres. The dam can hold 1.3 to 1.4
million litres
Although the Hannemanns had a clear
idea of what they wanted to create they
did not hesitate to engage experts. They
employed an earthmoving contractor
to build the dam and sought design,
construction and technical advice
from water containment experts
FABTECH, the local NRM Board
and an irrigation consultant. “Don’t be
frightened to ask for advice. Look at
things that are working. We researched it.
It didn’t happen by accident, it
was planned.”
The key water conservation points of
the Hannemanns’ water catchment
and reticulation system are:
harvest area means water is
collected at 98% efficiency.
water loss by soakage through the
dam wall.
prevents evaporation.
quality by excluding sunlight, which
reduces algae growth.
40mm poly pipe to small troughs in
each paddock. Water supply to the
troughs is turned off when there
is no stock in the paddock and the
small surface area of the troughs
minimises water loss through
evaporation.
Dam details
Catchmentarea 1
40m x 40m1600m2
Catchmentarea 2 &
sump40m x 40m
1600m2
Joined & sealed
Overflowpipe
1.3ML
Dam pipe
Vermin fence45m x 120m
Pipe & tap1.0ML
Pipe & tapoutlet atbottom of dam
Pipe to troughs over entire farm
Dam
30m x 30m
1.3ML
900m2
Rainfall (mm) calculations vs
catchment area (m2) in litres
Square Millimetres Litres metres
1m2 x 1mm rain = 1 litre
4100 x 250 = 1,025,000
4100 x 300 = 1,230,000
4100 x 350 = 1,435,000
4100 x 400 = 1,640,000
4100 x 450 = 1,845,000
4100 x 500 = 2,050,000
Spring Edition - October 2010 144 SANTFA - The No-Till Journal Vo l 7 No 4
Water security
FABTECH, which has extensive dam
construction experience in the mining
industry, brought up a team from
Adelaide to roll out and weld the plastic
on site. All the welds were pressure-tested
prior to project completion.
Fencing the catchment and dam was
essential to keep stock and wildlife from
tearing holes in the plastic and Mark did
all the fencing and pipe laying himself.
The dam has an overflow at the 1.3
million litres level and two main outlets.
The top outlet automatically siphons
the first 300,000 litres to a holding tank
five kilometres away at the main house,
leaving a million litres of water in the
dam but ensuring sufficient capacity to
accommodate future rain events. Any
overflow from the holding tank is directed
to the main house dam that was part of
the traditional dam infrastructure. As
a result the system has the capacity to
capture approximately 307,500 litres
of water; the run-off from a rain event
of 75mm.
The bottom tap outlet gravitates water 1,000,000 litres through a pipe system supplying water for stock, domestic use and farm spraying requirements, ensuring water security all year round.
Cost
The cost for the entire project was approximately $100,000, which needs to be compared to the alternatives. Carting a million litres of water in a dry year was costing Mark and Andrea approximately $11,500 - $10,000 in transport costs and $1,500 to buy the water.
When they costed the concept of accessing the SA Water supply they worked on $1.50 per kilolitre (1,000 litres) of mains water, assuming they could have negotiated easements through neighbouring properties and established the holding tanks and pumps required to access what was a diminishing supply from the River Murray. Based on that, they estimated the payback period for their water harvesting scheme at 10 years. With the recent rise in water rates the payback may now be closer to 7.5 years.
And that was just to get water to the boundary. Piping it to the house and paddocks would have been an additional cost.
Mark takes a long term view. “This will satisfy our water requirements for the next 25 years. It’s clean, green, sustainable, high-quality water.”
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Mark and Andrea Hannemann were
among 32 farmers from around
Australia who represented their regions
at the recent Climate Champions
Conference in Canberra.
This conference, which they described
as ‘overwhelming and inspiring’, was the
start of a three year ‘Climate Change
Champions’ program supported by
GRDC, Managing Climate Variability
and Meat & Livestock Australia.
The ‘champions’ are all taking action
to manage risks associated with climate
and weather on their farms and are keen
to share their knowledge with other
farmers. They are also acting as two-way
conduits for information exchange
between farmers and scientists on issues
relating to climate change adaptation
in agriculture.
Since the conference Mark and Andrea
have given several well-received
presentations about the changes
they are making on their farm at
climate forums held for farmers on
Eyre Peninsula.
Their liaison role between farmers and
researchers is on-going and they would
welcome visits to their farm or phone
or email contact from farmers from
all areas.
In addition to speaking about
their water harvesting project, the
Hannemanns are also promoting
awareness of the www.climatekelpie.
com.au. This new website, an initiative
of Managing Climate Variability,
provides links to information about
climate and numerous decision-support
tools to assist growers and advisers with
on-farm decision making.
The site also carries information
about the ‘climate change champions’,
whose approaches to tackling climate
change range from alley farming
to experimenting with bio char or
developing water-harvesting schemes.
Mark and Andrea believe helping
make EP farmers more resilient in the
face of climate variability is essential to
strengthening local communities.
“You don’t have a strong community
unless you have strong viable farmers
to hold it up.”
For further information contact
Mark and Andrea Hannemann,
08 8628 4036, 0428 284 136,
mahannemann@activ8.net.au
A plan of the water storage and distribution system.
Spring Edition - October 2010 145 SANTFA - The No-Till Journal Vo l 7 No 4
Water security
Climate change
When it comes to dealing with climate
change at the farm level Andrea believes
the key lies in tackling the things you can
do so it is easier to manage the increasing
variability in rainfall and temperature
occurring now and likely to continue in
the future.
Interestingly, she notes that the language
is changing. “We talk about rain events
now when we used to just call it rain! We
had a hailstorm event! There are more
severe events occurring and we need to
learn to manage them. With our water
system, when we have one of these big
rain ‘events’ we can actually harvest the
water and use it.”
The Hannemanns are of the opinion that
human activity is connected with climate
change. They see the introduction of
carbon trading in the future as something
farmers will need to educate themselves
about and believe farmers should view
agriculture’s role as a ‘carbon sink’ as an
opportunity worth pursuing.
Mark feels that of all the things farmers
can do to help manage climate
variability, “adopting no-till is a number
one priority.”
However, water security is also important
and Mark and Andrea are pleased with
their decision to pursue their own
sustainable supply.
“What we are doing now is exciting.
It sells itself, this water harvesting, I love
it! The water quality is excellent – no
impurities. Some of our dam water
might have had quality issues but this
water does not.”
The project stretched their finances and
they had to borrow to fund it, but they
thought it was such an important aspect
of their farm going forward that they had
to do it. “We believed it was a bigger risk
to our business NOT to go ahead with
the project.”
And while they don’t
think of themselves
as community leaders
their involvement
in the Climate
Change Champions
program has raised
their profile and
they are coming to
think there may be
different ways of leading. As Andrea
says, “I hope we are inspiring people in
some way, enabling them to see how we
have done it and encouraging others to try
something different as well.”
The reason – a near-empty conventional dam reinforces the reasons the new
storage was built.
The promise – a rainbow seems to mark the dam location during the construction phase.