Management of Large Irrigation Systems for Enhancing Water Productivity S.K. Ambast

1. Management of Large Irrigation Systems
f E h i W t P d ti itfor Enhancing Water Productivity
S K A b tS.K. Ambast
skambast65@gmail.com
ICAR-Indian Institute of Water Managementg
Bhubaneswar - 751023, Odisha (India)

2. Introduction
 World over about 18% of the cultivated land is irrigated World over about 18% of the cultivated land is irrigated
that contributes nearly 40% of the global food production
WRD hi l f l d ti t t d i d WRD as vehicle for planned time targeted progress raised
irrigation potential (20.9 in 1951 to 123.3 M ha in 2012)
 Enormous irrigation potential has been created at huge
cost (about Rs 16 billion/annum), the gap between created
potential and utilization is significant (32.2 M ha; 26%)potential and utilization is significant (32.2 M ha; 26%)
 Low conveyance (65-70%) and application (45-50%)
ffi i i lti l i i ti ffi i (35 40%)efficiencies resulting low irrigation efficiency (35-40%)
 Sustainability of irrigated agriculture is severely impairedSustainability of irrigated agriculture is severely impaired
due to waterlogging and salinity in arid & semi-arid regions

3.  8.4 M ha land (10 M ha by 2025) affected with soil salinity/
alkalinity. About 5.5 M ha land is in irrigation commandsalkalinity. About 5.5 M ha land is in irrigation commands
 Lack of systematic information on crop water productivity
d l i f ti t t l t d ti itand nearly no information on total water productivity
 Benchmarking WP at field, system and basin scale, wouldg , y ,
help to evaluate improvement options
I i it f t & l d d d ti i i i t d Increasing scarcity of water & land degradation in irrigated
areas may pose serious challenge to food security
 Substantial increase in output of water used particularly in
agriculture is essential to meet the goals of national food
d i t l itand environmental security

4. Water and Food Security: Challenges By 2050
20 Agro-Ecological Regions
Rainwater
Management Application
Efficiency
g g g
y
(+111 M t)
(-324 BCM)Canal Water
Water
Productivity
( 3 C )
National
Food
Security
Management
Water
Resource
Development
Productivity y
2050
(+20% IE)
(+46% WP)
Groundwater
Management
and
Management
( )
SustainabilityWastewater
Management
Climate Change

5. Marginal / Poor Quality Groundwater
Aquifers surveyed in different states in semi-arid regions indicated
about 32-84% of the ground water as poor quality in nature

6. Crop Water Productivity in India
Region/crops Land Productivity#
(Kg/m2
)
Avg. Exp.
Water Productivity
(Kg/m3
)
Avg. Exp.
Reference
RiceRice
Punjab
Haryana
Uttar Pradesh
Chhattisgarh
0.35 0.66
0.27 0.64
0.21 0.46
0 14 0 70
- 0.34
- 0.44
- 0.38
- 0 46
Hira et al. (2004)
Tyagi et al. (2000)
*
CSSRI (2005)
Mukherjee (1990)Chhattisgarh
Orissa
West Bengal
Karnataka
0.14 0.70
0.16 0.17
0.25 0.42
0.22 -
0.46
- 0.21
- 0.36
- 0.61
Mukherjee (1990)
Kar et al. (2004)
Ambast et al. (1998)
Manjunatha (2004)
WheatWheat
Punjab
Haryana
Uttaranchal
Uttar Pradesh
0.45 0.54
0.41 0.49
0.19 0.50
0.28 0.43
- 1.40
- 1.44
- 1.00
- 1.11
Hira et al. (2004)
Tyagi et al. (2000)
Mishra et al. (1995)
CSSRI (2005)
Crop water productivity (Kg/m3) = Yield (Kg/ha)/Water consumed in ET+ Losses (m3/ha)
# Average land productivity based on Statistical Abstract of India, 2003
* Authors reported water use efficiency as 1 1 kg/m3 on the basis of actual ET
West Bengal 0.22 0.30 - 1.15 Ambast et al. (1998)
Authors reported water use efficiency as 1.1 kg/m on the basis of actual ET

7. Irrigation System
POLITICO ECONOMIC SYSTEM
6
RURAL ECONOMIC SYSTEM
5
AGRICULTURAL ECONOMIC SYSTEM
4
IRRIGATED AGRICULTURE SYSTEM
2
3
IRRIGATION SYSTEM
2
1.Operation of irrigation facilities 3.Agricultural production 5.Rural development
2.Supply of water to crops 4.Incomes in rural sector 6.National development
1
Other Inputs Other Inputs

8. Basin
Level
Surface & subsurface
inflows and precipitation
Hydrologist
and
Economist
Rs/m
3
System
Level
Reservoir Storage losses
Inter-sectoral
allocation
Sinks Irri. Engineers
d S i l
A comprehensive
Conveyance
losses
Water released
and Social
Scientist
Kg/m
3
, Rs/m
3
Farm
p
framework for
water productivity
at different scales
Water delivered
at farm gate
Total water
available at farm
Return flow, Water-
table, Groundwater
Rainfall Ag. Engineers
and Ag.
Economist
Farm
Level
at different scales
(Ambast, 2005) Water applied
to field
Application losses
Sinks
Crop scientist
and
Field
LevelWater consumed
by crop
Water retained
in soil
and
Soil scientist
Kg/m
3
y p
Crop production
Breeders
and
Physiologist

9. Estimation of System Performance
in Large Irrigated Commandsg g

10. Water Productivity at Field Scale
Kaithal
Irrigation
Circle216 farmers in
6 watercourses6 watercourses
Crops Head reach Tail reach
Rice (Kg/m3) 0 47 0 37Rice (Kg/m ) 0.47 0.37
Wheat (Kg/m3) 1.90 1.50

11. Up-scaling Water Productivity to System Level
Branch canal commandBranch canal command
Distributary canal command

12. ETa (mm/d) on 31 Jan
Yield & Evapotranspiration at System Scale
Wheat crop yield

13. Crop Water Productivity in the SLLC System
At di t ib t
3 00
At distributary
level
1 50
2.00
2.50
3.00
Yield/WUE-S
Evp fract(-)
Yield(Kg/ha)
WUE(Kg/m3)
0 00
0.50
1.00
1.50
Evpfract/Y
(Source: Ambast 2001)
0.00
X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X12 X13 X14 X15
Distributary ID (Buxar Canal)
2.00
2.50
3.00
d/WUE-S
Evp fract (-)
Yield (Kg/ha)
WUE (Kg/m3)
0.50
1.00
1.50
vpfract/Yield
At branch
canal level
0.00
0.50
P A B D X C G W1 W2
Canal ID
Ev

14. Monitoring of Waterlogged & Salt Affected Crops
ConceptConcept
Bhalaut Canal Command (Haryana)
Total Area : 80,000 ha
Production Loss : 62000 tons
Economic loss : 37 m INR
WASAC-SRS
Economic loss : 37 m INR
Loss (% to potential) : 18%
(1 INR = 0.023 US$)
(Ambast et al., 1999)

15. Technological Options for Improvingg p p g
Water Productivity in Irrigated Environment

16. Spatial Decision Support System for
Conjunctive Use of Waters
Canal Network,
Design Discharge
Soil & Groundwater
Salinity Information
Cropping
Pattern
Farmers
P ti
Spatial Database Management System
E i M d lPractices Economic Model
Regression Models/
ANN
SWAP/CROPWAT
Farmers Decision &
Economics
Scientific Decision &
Economics
Comparison of
DecisionsEconomics Economics Decisions
(Ambast et al., 2004)

17. Farmers’ Decision-making and Yield Variation
35.0
40.0
)
Ground water
Canal water
18.3
22.2 25.5
21.8 30.1 32.2
1 0
20.0
25.0
30.0
pplication(cm)
Canal water
Irrigation application
by different sources
9.3 9.0 7.0 5.8
1.5 1.3
30.1
0.0
5.0
10.0
15.0
Waterap
BH BM BT RH RM RT
Watercourse
Location of Wheat yield (t ha-1
) Rice yield (t ha-1
)Location of
fields in
watercourse
command
Wheat yield (t ha ) Rice yield (t ha )
______________________ _______________________
Watercourse at Watercourse at
Head Middle Tail Head Middle Tail
Head 4.8 4.7 4.4 5.0 4.1 3.0Head 4.8 4.7 4.4 5.0 4.1 3.0
Middle 4.6 4.4 4.2 4.6 3.5 NR
Tail 4 4 4 3 3 7 4 5 3 4 NRTail 4.4 4.3 3.7 4.5 3.4 NR
Average 4.6 4.5 4.1 4.7 3.6 3.0
Yield variation in
Batta minor

19. 37 5
40
Conjunctive Use of Canal and Groundwater
Effect on relative wheat yield
32.5
35
37.5
m)
Ry
ect o e at e eat y e d
25
27.5
30
Depthofapplication(cm
17.5
20
22.5
35
36
37
38
39
40
1 2 3 4 5 6 7 8 9 10 11 12
Irrigation water quality (dS/m)
15
28
29
30
31
32
33
34
application(cm)
ECe
21
22
23
24
25
26
27
Depthofwater
1 2 3 4 5 6 7 8 9 10 11 12
EC of Irrigation Water (dS/m)
15
16
17
18
19
20
Effect on soil salinity at wheat
harvest (initial ECe 5.5 dS/m)

20. Precision Land Levelling for Improving WP
Conventional
Levelling
Laser
LevellingLevelling Levelling
Levelling index (cm) > 1.5 <1.5
Irrigation depth (cm)
Paddy
Wh t
110-115
30 35
90-95
20 25Wheat 30-35 20-25
Pumping req.(hr/ha/irri)
Paddy
Wheat
25-27
15-17
20-22
9-11
Water prod. (kg/m3
)
Laser land leveller
Paddy
Wheat
0.37
1.50
0.47
2.44
Profit Gains (INR/ha)
1st
year
2nd
year
-
-
1000-1200
4000-5000
Crop performance
2 year 4000 5000
Precision levelling (LI<1.5cm) not
only reduces application of water,
energy consumption and crop
losses, but also enhances water
productivity and economic returns.

21. 0.9
1
EC=1dS/m
EC=3dS/m
Irrigation Schedulling
Conventional Land levelling
0.6
0.7
0.8
yield,(%)
EC=5dS/m
EC=7dS/m
EC=9dS/m
EC=11dS/m
Co e t o a a d e e g
0.3
0.4
0.5
Relativey
0.1
0.2
1 2 3 4 5 6
Numberofirrigations
7
8
0.90
1.00
EC=1dS/m
EC=3dS/m
5
6
050
0.60
0.70
0.80
yield,(%)
EC 3dS/m
EC=5dS/m
EC=7dS/m
EC=9dS/m
EC=11dS/m
1
2
3
4
0.20
0.30
0.40
0.50
Relativey
0.00
0.10
1 2 3 4 5 6 7 8
Numberofirrigations
Precision Land Levelling

22. Alternate Cropping Pattern for WP Improvement

23. Deficit Irrigation/Alternate Cropping Pattern for
Improving WP
Crop Area
(%)
Prod Loss
(%)
Prod.
(kg)
WUE
Kg/m3
)
CP1
Wheat I 35 0 0 1575 0 98Wheat-I 35 0.0 1575 0.98
Wheat-II 20 1.5 887 0.96
Pulses+OS 15+5 2.8 194 0.47
Vegetable 3 2 5 585 5 11Alternate cropping Vegetable 3 2.5 585 5.11
Scane 2 0.0 1000 -
CP4
Wheat-I 50 4.3 2153 1.27
Alternate cropping
pattern and deficit
irrigation increased
Wheat-II 35 12.0 1386 1.17
Pulses+OS 5+5 7.2 93 1.28
Vegetable 3 2.5 585 5.11
Scane 2 0 0 1000
g
water productivity
and net benefit
Scane 2 0.0 1000 -
CP5
Wheat-I 60 4.3 2584 1.27
Wheat-II 40 12.0 1584 1.17
Net Profit(INR/ha): CP1-6050; CP4-8120; CP5-8750

24. 18.6.98
20.7.98
06.8.98
20.8.98
04.9.98
17.9.98
07.10.98
Artificial Groundwater Recharge through Tabewell
12
-8
-4
1
2
06
2
04
1
0
towatertable(m)
(a)
-16
-12
Time (day)
Deptht
with recharge tubewell
without recharge
6
98
7
98
8
98
8
98
9
98
9
98
10.98
-8
-4
18.6.9
20.7.9
06.8.9
20.8.9
04.9.9
17.9.9
07.10
watertable(m)
(b)
-16
-12
Time (day)
Depthtow
with recharge tubewell
without recharge
8
-8
-4
18.6.98
20.7.98
06.8.98
20.8.98
04.9.98
17.9.98
07.10.98
atertable(m)
(c)
-16
-12
Time (day)
Depthtowa
with recharge tubewell
without recharge

25. Recommended Design and Economics
Particulars Quantity Unit Cost
(Rs.)
Total Cost*
(Rs.)
1. Installationof pipewithboring(6” dia. bore
and4” dia PVC pipewithperforations
1No. @ 8000 8000
and4 dia. PVC pipewithperforations
2.Excavation & disposal of dug soil & refilling of pit
withfilter materials(3m*3m*3m).
3 P t f filt t i l
27.00 m
3
4 95
3
@ 50/m
3
@ 300/
3
1350
14853. Procurement of filter material
(a) Coarsesand
(b) Gravel
(c) Pebbles
4.95 m
3
8.55 m
3
13.50 m
3
@ 300/m
3
@ 350/m
3
@ 400/m
3
1485
2993
5400
Total Cost 19230Total Cost 19230
Cost of recharge - Rs 10 /100m3Cost of recharge Rs 10 /100m3
(Ambast et al., 2006)

26. Demand Management for Arresting Watertable Decline
Fallow land during kharif seasong
0 2 4 6 8 10
Uncropped land (% of CCA)
15.4
15.6
15.8
th(m)
NR-0
NW-0
NR-1
NW-0
Reduced irrigations (NR-2,
NW-1) and 10% fallow land
16.0
16.2
16 4
ertabledept
NR-0
NW-1
NR-2
NW-0
NR 2NW-1) and 10% fallow land
reverses WT decline by 25
cm/year in Guhla block
16.4
16.6
16.8
Wate
NR-2
NW-1
NR-1
NW-1

27. Groundwater Dilution & Use in Crop Production
at Recharge Site (Odara, Bharatpur, Rajasthan)
Name O.R.PYield t/ha Farmers yield (t/ha) % Increase
1. Mr. Jagan Singh 5.36 4.73 13.3
2. Mr.Mukesh Kumar 4.71 4.13 14.0
3. Mr.Birendra Singh 4.75 4.14 14.7
4. Mr Lal Hans 4.76 4.22 12.8
5. Mr Dinesh Chand 4.75 4.20 13.15. Mr Dinesh Chand 4.75 4.20 13.1
6. Mr Dhara Singh 5.01 4.35 15.2
7. Mr Ram Bharosi 4.50 3.90 15.4
8. Mr Roop Singh 4.80 4.10 17.1
25
8. Mr Roop Singh 4.80 4.10 17.1
9. Mr Hari Prasad 5.00 4.30 16.3
10
15
20
ECiw(dS/m)
Mr Hari Prasa
Mr Jagan Sing
Mr Mukesh K
Mr Ram Bhar
Mr Lal Hans
Mr Dinesh Ch
Mr Dhara Sing
0
5
Initial ECiw Ist irri. IInd irri. IIIrd irri. IVth irri. Vth irr.
Iirrigations
Mr Dhara Sing
Mr Birendra S
Mr Roop Sing

28. Crop Management: Saline Irrigation Water
Crops Soil ECiw for relative yield
90% 75% 50%
Wheat - pearl millet
(Agra - 6 yrs)
Sandy loam 6.6 10.4 16.8
Wh t h S d l l 3 4 7 0 12 9Wheat - sorghum
(Dharwad - 5 yrs)
Sandy clay loam 3.4 7.0 12.9
Wheat - maize
(Indore – 8 yrs)
Clay loam 4.7 8.7 15.2
(Indore 8 yrs)
Mustard - cluster bean
(Jobner - 2 yrs)
Loamy sand 6.6 13.5 -
Mustard - Sorghum Sandy loam 6.6 8.8 12.3
(Agra – 6 yrs)
Mustard - soybean
(Indore - 5 yrs)
Sandy clay loam 3.8 7.9 14.7
• Crops vary in their tolerance to ECiw
• Oilseed crop require less water, are more tolerant to high ECiw
• Pulses are very sensitive to saltsPulses are very sensitive to salts
• Higher salinity water could be used in coarse textured soils
• In summer, crops show less tolerance to Eciw

29. Irrigation Management: Conju Use (Saline/Canal water)
Treat Seed Relative Water Wheat Relative WaterTreat
ments
Seed
cotton
yield (t/ha)
Relative
yield (%)
Water
productivity
(kg/m3)
Wheat
yield
(t/ha)
Relative
yield (%)
Water
productivity
(kg/m3)
IW TW IW TW
C 3.42 100 1 90 0 66 5.71 100.0 1.90 1.42C 100 1.90 0.66 5.71 100.0 1.90 1.42
1C: 1S 2.93 85.7 1.63 0.57 5.40 94.6 1.80 1.36
1S: 1C 2.80 81.9 1.56 0.55 5.22 91.4 1.74 1.32
2C:1S 3.32 97.1 1.84 0.64 5.58 97.8 1.86 1.40
2 032S:1C 2.03 59.4 1.13 0.40 4.16 73.0 1.39 1.06
S: RTC 3.02 88.3 1.68 0.59 4.64 81.3 1.55 1.18
C: RTS 2.79 81.6 1.55 0.55 4.74 83.1 1.58 1.21
S 1.94 56 7 1 08 0 39 3.91 68.4 1.30 1.00S 56.7 1.08 0.39 3.91 68.4 1.30 1.00
CD(5%) 0.21
(AICRP:2010-12)

30. Irrigation Management: Conju. Use (Alkali/Canal waters)
2500
40
45
R
CW
1500
2000
20
25
30
35
nfall (mm)
SP
AW
Cyc(1YCW:2YAW)
Cyc(2YAW:1YCW)
Cyc(2YCW:1YAW)
500
1000
5
10
15
Rain
E
Cyc(1YAW:2YCW)
Cyc(AWp:CWs)
Blend(2CW:1AW)
Blend(1CW;2AW)
00
2003‐04 2004‐05 2005‐06 2006‐07 2007‐08 2008‐09

31. Irrigation Management: Method & Frequency
Treatments
ECiw levels (dS/m)
Capsicum (t/ha) Okra (t/ha)
Drip Surface Drip Surface
Canal 16.74 12.78 11.19 10.79
4 11.92 8.84 5.27 2.74
8 10.19 7.68 2.93 0.01
CD (5%) 2 37 1 37 1 26 1 14CD (5%) 2.37 1.37 1.26 1.14
IW/CPE ratio
0.75 13.02 10.03 4.58 4.50
1.00 13.61 9.87 6.79 4.58
1.25 12.22 9.21 8.03 4.43
CD (5%) NS NS 1.26 NS
EC x IW/CPE ratio NS NS 3.15 NS
Treatments
ECiw levels (dS/m)
Drip irrigation Surface irrigation
Water use
(cm)
Water prod
(kg/ha-cm)
Water use
(cm)
Water prod
(kg/ha-cm)
Canal 46.9 240.4 64.9 166.7
4 47.7 116.0 64.3 44.3
8 43.6 71.0 64.0 0.2
IW/CPE ratio
0 75 35 9 127 5 50 5 89 30.75 35.9 127.5 50.5 89.3
1.00 47.8 143.4 64.7 71.5
1.25 57.6 139.4 78.4 57.7
(AICRP:2010-12)

32. M i d i ld f d t ith
Irrigation Management: Groundnut-Wheat under MI
Maximum pod yield of groundnut with
BAW (EC 0.25dS/m), saline water (EC 4.6
dS/m) and mixed waters (EC 1.56-3.24
dS/m) obtained at water depth of 60 50dS/m) obtained at water depth of 60, 50
and 55 cm respectively.
For obtaining higher yield of wheat under
sprinkler irrigation the depth of water
applied is to be kept around 42, 33 and
38 cm for BAW, saline and mixed water,
ti lrespectively.

33. Water Saving & Increase in Area by Drip Irrigation
Centre & State Test Crops Soil type Water saving (%) Area Increase
(times)(times)
Dapoli (MS) Brinjal Lateritic 38 1.6
Navsari (Guj) Onion
Turmeric
Clay 30
32
1.4
1.5Turmeric
Chilly
32
48
1.5
1.9
Bhawanisagar (TN) Jasmine
Sugarcane
Sandy loam 50
40
2.0
1 7Sugarcane
Tomato
Banana
40
42
48
1.7
1.7
1.9
Madurai (TN) Sugarcane Clay loam 21 1.3
Red Gram 39 1.6
Kota (Raj) Onion
Garlic
Clay loam 23
22
1.3
1.3
Turmeric 23 1.3
Faizabad(UP) Sugarcane
Marigold
Cowpea
Silt loam 59
55
61
2.4
2.2
2 6Cowpea 61 2.6
Palampur (HP) Broccoli
cauliflower
Silty clay loam 47
38
1.9
1.6

34. Increase in Yield by Drip Fertigation
Centre & State Test Crop Soil type Yield (kg/ha) % Yieldp yp ( g )
increaseConventional Fertigation
Dapoli (MS) Brinjal Lateritic 1876 3234 72
Jorhat (Assam) Assam Lemon Sandy Loam 10100 14880 47( ) y
Palampur (HP) Broccoli Siltyclayloam 7400 8440 14
Navsari (Guj) Onion
Turmeric
Clay
Clay
28740
13100
45690
16800
59
28Turmeric
Round melon
Sugarcane
Tomato
Clay
Clay
Clay
Clay
13100
12000
140000
48000
16800
15300
183000
68000
28
28
31
42
Bhawanisagar
(TN)
Coconut (Nuts)
Sugarcane
Sandy loam 10974
115300
16461
171700
50
49
Madurai (TN) Red Gram Clay loam 1108 1515 37
Kota (Raj) Onion Cabbage
Garlic Turmeric
Bitter Gourd
Clay loam
Clay loam
Clay loam
Clay loam
16350
17756
6953
14670
24960
23373
10575
27360
53
32
52
87Clay loam
Clay loam
14670
21226
27360
30139
87
42
Faizabad (UP) Marigold Silt loam 161 216 34

35. Conclusions
 In the changing climate scenario, water will be
increasingly scarce, it is important to understand the
concept and utility of water productivity at field,concept and utility of water productivity at field,
system and basin level.
Benchmark information on ater prod cti it ma be Benchmark information on water productivity may be
useful to assess the scope of water productivity
improvement by different improvement interventions.
 Technological interventional i.e. conjunctive use of
waters, precision land levelling, deficit irrigation,, p g, g ,
alternate cropping system, diversified land use and
multiple use of water may help in improving water
productivity in saline irrigated commands.productivity in saline irrigated commands.

36. Water Productivity - Policy Issues
How effective is water productivity estimation at farm How effective is water productivity estimation at farm,
system and basin scale to assess the scope and
measure for improvement?
 Operation system research to evolve scientifically based
region specific integrated farming system componentsregion specific integrated farming system components.
 Assessing sustainability implications of long-term and Assessing sustainability implications of long term and
large-scale implementation of multiple uses of rain/canal
and saline ground waters in different sub-regions.
 Trade-off between hydraulic means of improving water
productivity and saved water worth in different regionsproductivity and saved water worth in different regions.

37. Thank you