dr aftab ahmad july 10-11, 2017 - mucp-mfit
TRANSCRIPT
Over one million Sq. kilometre area
Covers 14% of country’s area over 5 states
20 major rivers
Only 6% of annual rainfall (165mm/year)
40% of country’s agricultural production
70% comes from irrigation
Salinity and Drainage Strategy (1989) In the mid-1980s more that 96,000 hectares of irrigated land
in the Basin were showing visible signs of salinisation It was estimated that the irrigation areas affected by high
water tables could increase from 559,000 hectares in 1985 to 869,000 hectares in 2015
increase in river salinity largely due to contributions from an increase in groundwater mounds under irrigation areas,
and surface and sub-surface drainage from the high water table areas
Each State responsible for actions significantly affecting river salinity taken within its jurisdiction
Introduction of salinity register to maintain salinity credits/debits
Cap (1997) Limit on the volume of water that could be diverted from the rivers in the
basin for consumptive use (mainly irrigation) from 1997 after realizing that ongoing increase in consumptive use of water in the Murray-Darling Basin (MDB) was environmentally and socially unsustainable.
This limit is called the cap and effectively limits the volume of water diversions to 1993/94 development level.
No additional water could be diverted from the river for new developments. Positive outcomes:
▪ River health, ▪ impetus for water saving by improvement in water use efficiency, and water trading. ▪ The improvement in irrigation efficiency helped control rising watertable in
inefficiently irrigated areas▪ Made water available for new irrigation developments and ▪ Water trading provided a market mechanism to temporarily shift water from low value
to high value use.
Discrepancies in Cap implementation and monitoring
National Water Initiative (2004) Agreed in 2004
Under NWI, governments have made commitments to:▪ prepare comprehensive water plans
▪ achieve sustainable water use in over-allocated or stressed water systems
▪ introduce registers of water rights and standards for water accounting
▪ expand trade in water rights
▪ better manage urban water demands.
Water Act 2007 (2007) 10 year 10 billion water for future program
Federal government given more regulatory power to reform the Murray-Darling basin.
Water charge and water market rules functions given to the Australian Competition and Consumer Commission.
Functions in relation to water information given to the Bureau of Meteorology.
Established Murray-Darling Basin Authority.▪ Responsible for overseeing water resource planning in the
Basin
▪ Basin Plan
Water Act 2007 (2007) cont’d...
Basin plan
▪ Sustainable diversions limit
▪ Buyback
▪ Supply measures
▪ Efficiency measures
Water Trading
▪ Improved market mechanism and transparency
Established the Commonwealth Environmental Water Holder
▪ Manages Commonwealth’s environmental water portfolio.
Water is a tradable commodity and has an economic value One of the driving factors behind the trend for water use
efficiency improvement Institutional reforms:
creating water markets and regulatory framework decoupling water and land property rights, and allowing water to flow from low value uses to high value use
with minimum of transaction costs Water trade price has been as high as $1,062/ML during
drought periods. The average water trade price from 2005-06 to 2010-11 in
MIA: $271/ML Tradeoffs between water trading and environmental and
equity goals
Murrumbidgee Irrigation Area Total irrigated area: 3,624 sq. km Total surface water use for irrigation: 1,250 GL 8% of the area is covered by horticultural crops Average rainfall: 530 mm/year Average potential evapotranspiration is 1000 mm/year
Murrumbidgee Irrigation Area Over 3500 km of irrigation supply channels Only 250 km are lined and 100 km are piped Seepage loss as high as 20 mm/day
Shift in irrigation systems in MIA (% of total irrigated area)
17.2
52.9
23.2
0.9 0.3 3.5 2.0
DripFloodFurrowLow headMicrojetSprinklerOverhead
0.7
91.2
0.25.6
2.3
drip/subsurface/trickle
surface
fixed overhead sprinklertravelling irrigator
moveable spray
2003
2009
An unintended consequence of technology adoption to achieve improved water use efficiency is the significant increase in energy use and energy cost and its long-term impacts on climate change
Energy input in agriculture is directly related to the level of technology adoption and the level of production.
N2
N3
N4 N5 N6
N7
N8
N9
N10 N11 N12 N13
WaterSource
N1a
N7a
(273) (552)(291)
(102)
(446) (150)
(368)
(100)
(585)
(508)
(271)
(324) (4) (94)
Schematic of 13 farm nodes and supply link
Scenario 1: Furrow –gravity
Scenario 2: Sprinkler with pressurised irrigation
Scenario 3: Drip with pressurised irrigation
Ph1
PumpEfficiency
N2
N3
N4
N5
N6
N7
N8
N9
N10 N11 N12N13
ETc_adj_3
ETc_adj_4
ETc_adj_5
ETc_adj_6
ETc_adj_7
ETc_adj_8
ETc_adj_9
ETc_adj_10
ETc_adj_11
ETc_adj_12
ETc_adj_13
TotalDynamic
Head
ReservoirN1
Total_DutyFlow_Rate
TotalPumpPower
PumpDischarge
No._of_Pumps
O3vel
O4vel
O5vel
O6vel
O7vel
O8vel
O9vel
O10velO11vel O12vel
O13vel
Rn1
Rn2
Rn3
Rn4
Rn5
Rn6
Rn7
Rn8
Rn9
Rn10
Rn11 Rn12
Rn13
f1
f2
f3
f4
f5
f6
f7
f8
f9
f10
f11f12
f13
Hf1
Hf2
Hf3
Hf4
Hf5
Hf6
Hf7
Hf8
Hf9
Hf10
Hf11
Hf12 Hf13
Ph2H2
Ph3H3
H4Ph4
H5Ph5
H6Ph6
H7
Ph7
H8
Ph8
H9
Ph9
H10
Ph10H11
Ph11
H12
Ph12
H13
Ph13
H1
N1a
ETc_adj_1a
O1avel
Ph1a
Hf1a
f1a
Rn1a
H1a
N7a
ETc_adj_7a
Hf7a
f7aPh7a
Rn7a
O7avel
H7a
CumulativeEnergy_Use
CumulativeIrrigation_Volume
I1a
I10
I11
I12
I13
I3
I4
I5
I6
I7
I7a
I8
I9
RZ_depletion
1a
BrakePower
Motor_Efficiency
Total_Dynamic_Head
200
150
100
50
0
1 53 105 157 209 261 313 365
Time (Day)
Total_Dynamic_Head : WithIrrRateDrip m
RZ_depletion_6
Ks_6
RZ_depletion_3
RZ_depletion_7
RZ_depletion_8
RZ_depletion10
RZ_depletion11
ETc6
RZ_depletion_5
Ks_5
ETc1a Ks_1a
ks_3ETc3
RZ_depletion12Ks_12
ETc12RZ_depletion
13Ks_13
ETc13
Ks_7ETc7
ETc8
ETc5
Ks_10
ETc10 Ks_11
ETc11
RZ_depletion_4
Ks_4ETc4
RZ_depletion7a
Ks_7aETc7a
RZ_depletion_9
Ks_9
ETc9
Ks_8
RZD_6
DP_6
RZD_5
RZD_4
RZD_3
RZD_1a
RZD_7
RZD_7a
RZD_8
RZD_9
RZD_10
RZD_11
RZD_12
RZD_13
DP_5
DP_1a
DP_12
DP_13
DP_3
DP_7
DP_10
DP_11
DP_4
DP_7a
DP_8
DP_9
Ev6
Ev5
Ev1a
Ev3
Ev7
Ev10
Ev11
Ev4
Ev7a
Ev8
Ev9
Ev12
Ev13
Cum_evap_lossCum_DP_loss
Water_Availability Water_Trade_Price
Investment_on_WaterSaving_Irrigation
-
+
Irrigation_WaterSavings
+
+ Water_savings
per_$_invested
Climate_change
Climate_shift
Change_in
policy_settings
+
-
Irrigation_WaterSavings
+
+ Water_savings
per_$_invested
PumpingEnergy_Use
GHGEmissions_Tax
Net_Returnfrom_Saved
Water
+
+
-
- Energy_use_per
ML_savings
Emissions_per
KWh_energy_use
Scenario 1: Furrow – gravity (labour intensive)
Scenario 2: Sprinkler with pressurised irrigation
Scenario 3: Drip with pressurised irrigation
0
2,000
4,000
6,000
8,000
10,000
1 2 3
En
erg
y U
se (
kW
h/h
a)
Scenario
Citrus
Stone fruit
Wine grapes
0
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
180,000
200,000
20 30 40 50 60 70 80 90 100
Wat
er u
se (M
L) &
En
erg
y u
se (M
Wh
)
Percent of MIA horticultural area covered (%)
Total water use - drip (ML) Total water use - sprinkler (ML)
Total energy use - drip (MWh) Total energy use - sprinkler (MWh)
Adaptive management and policy responses to address the evolving water challenges.
Both water and energy have implications on sustainable development of agricultural production systems.
Water and energy use are strongly interlinked in irrigated systems.
Irrigation efficiency should be considered at system scale incorporating technical, economic & environmental aspects.
Need for finding an optimum level of adoption and appropriate mix of technology.