Preventing droughts in Australia
White paper on how to effectively tackle
Australian drought by improving water availability and reducing water usage
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+61 468484436
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Abstract:
By means of
this white paper I wish to suggest an approach that can help reduce the problem
of droughts, help farming communities, in the process help thousands of people and
the Australian economy too. At the federal and local level, we keep spending
billions of dollars each year on drought relief measures, instead if we can
spend an equivalent amount for forward looking initiatives, this would enable
us to better be prepared for droughts in future and hence won’t have to incur
significant expenses in future drought relief measures.
This might also
help in reducing our incidents of bushfire occurrences as the more moisture is
in atmosphere at a time, the more time it takes for the fire to start burning
over there as first the moisture must dry up before the fire can take hold.
On a
broad level, there are only two methods
to tackle the shortage of water – reduce consumption of water or increase water
availability. This paper focusses on one
way by which we can cut down water
consumption in half at a domestic
level and three ways to make
more water available for use by the entire country and not just major
metropolitan areas i.e. not just the main cities.
How
we go about achieving the same is what this white paper focusses on.
Background:
The drought
problem in Australia has been from beginning of time primarily because of the
massive size of the continent as moisture laden winds unleash rains only on the
areas close to the coasts and rest of continent remains parched.
Historically,
most of the calculations that we have always derived as to the water demand
have been based on the demand of the main metro cities because that’s where the
bulk of our population resides (62% as per 2011 census)9. It’s time
we also consider the other 38% population of the country where the bulk of rural
communities are located and where farming is extensively undertaken and in
times of droughts, they are the worst hit as compared to metro areas. The
farming community doesn’t enjoy a water laden period during official
non-drought times either, it is always in need of more water to manage the dry
interior landscape.
The dry nature
of the continent and water scarcity isn’t going to go away anytime soon, so
what we can do to prevent the recurrence of droughts is to keep our reservoirs/natural
bodies full with water by reusing every single drop that falls as rain or is
collected from ocean by desalination endlessly until we loose it to nature by
natural causes like evaporation or others.
By doing so we
should be able to make the main cities self-sufficient in their water demand
and consumption and not rely on the upstream dams thereby making the upstream
water available for the farming and rural communities in totality not only in
times of droughts but other times too.
For example,
the daily demand for water in Sydney region is 1.58 billion litres/day or 585 billion litres/year, this
can be more than met from the existing Sydney region itself by tapping a
combination of stormwater(500 billion
litres), waste water treatment(392
billion litres) and existing 250ML/day desalination plant(91 billion litres). The combined
capacity is almost half of the storage capacity of Warragamba dam in NSW
Ways
to create and save water:
Before deep
diving into the steps, it is essential that as a country and it’s people we
stop bothering ourselves from the source of the water i.e. is it desalinated,
recycled or rainwater. If the water coming into our taps from our respective
water authority is certified safe then we should be satisfied.
1.
Rainwater:
Tap
each drop of rain water throughout the country, though rainwater is harvested
by many homes and apartment complexes, storm water remains mostly wasted away other
than the one which empties into local reservoirs.
The
primary challenge has been storage of storm water as it has all sorts of
pollutants in it and storing without cleaning it first would create health
issues. This can be addressed by upgrading capacity of existing desalination
and waste water treatment plants to accommodate storm water cleaning as well,
storm water drains to be rerouted to the treatment plans instead of emptying
into the ocean. Once cleaned it should be pumped out to local reservoirs for
storage for future use.
The
approach to be adopted would vary depending on the type of location:
o
Urban : Water from storm water drains that
otherwise goes into the oceans should be redirected to water treatment plants
where it can be stored and treated using tertiary water treatment(6).
Sydney region’s 447km long storm water network(5% of NSW Stormwater network)
empties 500 billion litres/year
of water into the sea(2). The potential to harness water from all
storm water drains brings it up to 2
trillion litres/year of water in greater Sydney area alone. This can
further be scaled up later to tap all those areas where storm water network is
missing.
o
Rural :
In absence of a network of storm water drain network, water currently
flows to a local reservoir or flows off into the river or is lost due to
evaporation or a combination of the above. In areas where it doesn’t flow to
reservoir or river, it needs to be stopped in the gully by planting native
species with greater ground water penetration to aid the seepage of rain water
into ground faster. The plants would also prevent soil erosion and run off
water
o
Semi-Rural : In places where there is limited storm water
drain network, create local water treatment plants that would capture all the storm
water, treat it and make it available for usage or storage.
2.
Waste
water treatment and reuse
Reuse the treated
waste water from waste water treatment plants of the state, the same water that
is otherwise let into the ocean or the rivers(Greater Sydney region alone
empties more than 1 billion
litres/day of treated water into the ocean/rivers(1)).
Of
these 1 billion litres, 89% is primary treated, 8% is secondary treated and 3%
is tertiary treated(6)
If
we can reuse this entire water instead of emptying it out into the ocean, we
should be able to generate significant amount of water, similar what Israel
does with the Dan Region Wastewater Treatment Plant where a major part of
sewage water is treated and reused for agriculture.
3.
Desalination
Upgrade
existing waste water treatment plants to desalination plans, all of them exist
along the coastline so sourcing the sea water isn’t a challenge. We can infuse
2 billion litres of water everyday into the network. We can get some good learnings
from Israel which managed to build the largest desalination plant globally at a
cost of USD$500 million that produces more than 627ML of fresh water per day(8)
4.
Grey
water reuse
Grey water
produced at a domestic level forms more than half of a household’s daily water
need, by mixing it up with black water and disposing it off into sewage network
we are wasting valuable reuse opportunity at household level itself.
Properly
treated at a house/apartment level, grey water can be safely reused for
toilets, gardens, driveways, farming and other ancillary uses thereby bringing
down consumption by 40%.
Grey
water reuse becomes more important in rural communities and those communities
that rely solely on rain/spring water for their water needs and are not
connected to the water network for their farming and household needs.
The current
grey water reuse mechanisms require lot of rework and can cost thousands of
dollars without ever being able to recover that cost by means of water savings,
newer devices that are compact, create minimum disruption and are less than
$100 can be made available.
Solution
Options:
Option 1:
- Desalination : Upgrade existing waste water treatment plants along the coast to desalination plants, this along with the existing desalination plant should meet the entire daily water needs of Sydney region.
- Rain and waste water : Setup new waste water treatment plants in outer periphery regions of Sydney region like Penrith, Dural, Badgery creek, Berowra and so on to capture and treat storm and waste water generated from entire Sydney stormwater network that doesn’t flow into reservoirs. This treated water would then be supplied to rural NSW region.
- River water/Dams : Existing water supply from existing dams to be rerouted to regional areas and let the local council decide on best use of the water, either for existing farmlands or new farm lands or creating new forests/marshlands to make them more fire resistant.
Positives:
- Water supply for metro regions no longer left to mercy of rains and dam levels, there would be a defined desalination capacity and defined demand
- Rural areas would start getting assured water supplies and would also move away from being solely reliant on rains
- More areas to come under green cover like farms, forests or marshland
- Scalable for future needs
Not so positives:
- Costs involved would be high as it would involve setting up new waste water treatment plants, upgrading existing plants to desalination levels, changes in flow of water in pipeline network
Option 2:
- Rain and waste water : Upgrade existing waste water treatment plants along the coast from primary and secondary levels to tertiary levels so that water is fit for human consumption. These would filter all waste and storm water from Sydney region and pump it back into same Sydney region for consumption.
- Desalination : Existing desalination plant should meet the daily needs of Sydney region.
- River water/Dams : Existing water supply from existing dams to be rerouted to regional areas and let the local council decide on best use of the water, either for existing farmlands or new farm lands or creating new forests/marshlands to make them more fire resistant.
Positives:
- Reliability on rain would be reduced as most of the water needs would be met by desalination or waste and storm water reuse
- Less costly affair as compared to option 1 as less changes would be required.
- Rural areas would start getting assured water supplies and would also move away from being solely reliant on rains
- More areas to come under green cover like farms, forests or marshlands
Not so positive:
- Currently water flows one way i.e. from city to waste water treatment plants and then into the ocean, pipeline network to be enhanced to pump the treated water back in the network
- Reliability on rain water is not completely removed from picture and remains unless more desalination plants are setup to remove it totally
Option 3:
- River water/Dams : Existing water supply from existing dams to continue the same way as it is right now
- Desalination : Existing desalination plant to continue the same way.
- Rain and waste water : Upgrade existing waste water treatment plants along the coast from primary and secondary levels to tertiary levels so that water is fit for human consumption. These would filter all waste and storm water from Sydney region and this can then be pumped to regional NSW areas by new pipelines.
Positive:
- Hardly any change to existing Sydney water network
- Regional areas to get more water and thereby reduce their dependency on rains totally
- Least expensive option
Not so positive:
- No substantial change in water availability for regional areas
- New pipelines to be established might prove to be quite challenging, unwieldy and excruciatingly long.
Project
benefits
Economic
benefits:
1.
Direct benefit to the entire state as water would be
available in plenty, more benefit to farming communities as they don’t have to
suffer from droughts
2.
Extensive construction activity would have to take
place to upgrade existing water treatment plants to tertiary level or to
desalination standards or build new water treatment plants
3.
New water reservoirs to be built or existing
reservoirs to be upgrades
4.
Pipelines leading to the new or supplement existing
water reservoirs
5.
Water treatment requires energy is no secret so more
business for energy companies as well
6.
New areas to come under irrigation facilities from the
water reservoirs thereby leading to less depressed rural farming community and
more produce available for local consumption and export purpose
7.
Operation of the water treatment plants (typically to
be done by local council)
8.
Periodic maintenance and upkeep of pipes and motors
installed
Talent
and jobs:
9.
Construction jobs in plenty
10. Transportation
jobs
11. Water
management experts when it comes to upgradation of existing sewage treatment
plants to tertiary or desalination or create new plants
12. Project
management jobs
13. Local
water plant maintenance and upkeep jobs
14. Geological
talent would be needed to study terrain to judge areas that can retain water in
shallow rock formations
15. Electrical
engineering works to sort out the nuances of motors required to pump water in
the same pipeline network through elevations
Environment
benefits:
16. Constant
availability of water locally and in foliage increases the local humidity
levels and brings down temperature
17. Plantation
of evergreen trees that are fire resistant also contribute to bringing down the
local temperature thereby decreasing fire threat
18. Plantation
of more trees in hitherto dry lands in addition to benefiting agriculture also
reduces our green house emissions as we are offsetting the carbon dioxide
generated by trapping it for long inside the trees.
Storage
of water
On an average
annual loss of water across reservoirs and open water bodies in Australia is
between 6-10%. With rising global temperatures this loss is set to increase,
however we should also look at alternatives where we can reduce this loss, a
few suggested methods are as below:
-
Store the water in underground reservoirs(natural or
man-made) as the underground reservoir technology is tested and ready to use,
it helps (more than 10% depending on geographical conditions)in preventing loss
of water due to evaporation(7)
-
New reservoirs if required, to be created deeper and
surrounded by windbreaks such as trees and forests that reduces the flow of
moving air and also helps keep the temperature of environment low by means of
transpiration.
-
Run off into the marshlands/wetlands to keep them wet
as they are supposed to be to act as a buffer with the fire
-
Create new marshlands, ideally in the prominent fire
prone areas to act as first line of defense when fire comes calling
-
The result should be, a grid of water bodies would be
created at periodic intervals like 100kms so that access to clean water is
never too far.
Conclusion:
Water – elixir
of life can be reused repeatedly over and over again with full control over
quality of the nutrients and much to benefit of all our communities, all it
requires is willingness, cooperation and investment
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