The document discusses the large-scale installation of a subsurface drainage system in the Chambal command area of Rajasthan to address severe agricultural issues such as waterlogging and soil salinity. It outlines the project's objectives, methodologies, and outcomes, including significant improvements in crop yield and reduction in soil salinity over time. The benefits realized include enhanced crop production and greater water management, ultimately leading to increased agricultural sustainability in the region.

1. LARGE SCALE INSTALLATION OF
SUBSURFACE DRAINAGE SYSTEM
in Chambal Command, Rajasthan
Er. C.M. Tejawat, F.I.E., P. Eng.,
B.E. (Ag.), M.Sc. (Land Drainage Engineering)
Deputy Director (Monitoring), CAD Chambal, Kota (Raj.)

4. Gandhi Sagar Dam (M.P.) Rana Pratap Sagar Dam (Raj.)
Jawahar Sagar Dam (Raj.) Kota Barrage (Raj.)

5. LIFE LINE OF HADOTI

6. Left Main Canal
(Rajasthan)
Right Main Canal
(Rajasthan & M.P.)

7. G.C.A. 4,85,000 ha Command Area - Chambal
C.C.A. 2,29,000 ha
Districts wise CCA
Kota – 1,04,000 ha
Baran - 28,000 ha
Bundi – 97,000 ha

8. Chambal Command Area, Rajasthan
Irrigable Area 2,29,000 ha.
Irrigation 1960
Started
Soils Uniform Clay – Loam
Vertisols
Below 1.5 – 2.0 m
• Yellowish brown heavy clay
layer
Yellow silty clay (murrum
layer) 20-30 m with higher
permeability

9. PROBLEMS
Waterlogging in the fields of head reaches.
Increase in Salinity and Alkalinity of Soil.
Decrease in Crop Production.
Wastage of Irrigation Water .

10. Extent of Problem
Water logging : 1,61,000 ha.
Soil Salinity : 25,000 ha.

11. UNDP Project
To find means to protect the Land from Salinity and
Waterlogging.
To study problem of weed control in existing
Irrigation Canals and Drains.
To Design and Execute Irrigation Improvement,
Land Shaping and Drainage on Pilot Areas.
To develop proper Water Management Principals
and to make recommendations.
To develop proper Land Use Pattern and Farm
Practices for Intensification of Agriculture.

12. World Bank Project
Started in 1974
Planned to provide Surface Drainage in 1,67,000 ha
area.
74 Drainages Sub-basins identified having
Waterlogging problem.
Sub-basin 1000-10,000 ha
A Main Drain
Several Secondary Drains at about 500 m
spacing.
Seepage drains alongside the canals.

15. Command Area Development Project
Main Objectives
Improvement and increase in the Capacity of Canal.
Increase in Crop production with the help of improved
Agriculture Techniques.
On-Farm Development Works.
The Major thrust was given to On Farm Development Works.

16. On Farm Development Works
Objectives
Efficient water utilization to increase Irrigated Cropping
Intensity.
Maximum yields by scheduling Irrigation water application,
providing adequate drainage & better cultivation
techniques.
Easy access to individual field through improved road
network.
Shaping the Land to enable efficient Irrigation of field
Crops.

17. O.F.D. Works
Construction of Irrigation & Drainage ditches for each
field.
Providing road network to each field.
Land shaping for efficient Irrigation.
Re-alignment of the farm boundaries.

23. RAJAD
Rajasthan Agriculture Drainage Research Project
(1992-1999)
INSTALLATION OF
R SUBSURFACE
DRAINAGE SYSTEM
A in Chambal Command,
Rajasthan
J
A
D

24. Selection of Reclamation Technology
Subsurface Drainage + Surface Drainage +
On Farm Development Works
Provides an integrated soil and water management
program to optimize sustainable crop production in saline &
waterlogged lands.
Chambal Command Area-Rajasthan

25. Area Selection
•RAJAD Project - 25,000 ha
Salinity
Ec > 4 dS/m in top 1.5 m soil profile in at least
50% of the selected area.
Waterlogging
Water table depth < 40 cm in 70% of the area
for duration of at least 3 days.
Water table depth < 1.2 m in 70% of the area
for a continuous duration of at least 30 days
during an average rabi/kharif season.

26. Area Selection

27. Drainage Investigation
ECe (dS/m) Area Area
(ha) (%)
0-2 24569 48.90
2-4 7743 15.41
Sub Total for 32312 64.31
non saline area
4-8 12869 25.61
8-16 4510 8.98
>16 555 1.10
Sub Total for 17934 35.69
saline area
Grand total 50246 100.0

28. Area Selection
•280 Observation wells installed
•256 ha (1600 m grid)
•2.5 m deep & 1.5 m deep
•Measurements were taken on weekly basis
•Farmers Participation was involved
•Data of 275 wells were analysed
•Monitoring period Dec. 94 to Jan. 97

29. Area Selection

30. Area Selection

31. Drainage Investigation
Use of Total Station Survey Equipment

32. Drainage Investigation
Auger Hole Method

33. Data Storage and Retrieval
Computerized Central Data Base
System

34. Development of Design Criteria
• 12 Research Sites
International
• 4 years of data monitoring Panel of Experts
& analysis

35. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Saturated Hydraulic Conductivity
• Measured at 1.0, 1.5, 2.0 & 2.5 m depth
• Grid 8.58 ha
• Test plot results indicated:
•Top 1 m 0.25 – 0.55 m/day
•1 – 1.5 m 0.02 – 0.20 m/day
•Below 1.5 m 0.75 m/day

36. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Geometry of a Transient State Drainage System

37. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Modified Glower Dumn Equation
0.5 −0.5
⎡K *d *t ⎤ ⎡ ⎛ H 0 ⎞⎤
L=π⎢ ⎥ * ⎢ln⎜1.16 * ⎟⎥
⎣ μ ⎦ ⎣ ⎝ Ht ⎠⎦
H0
d = de +
2
L
de =
8*f h
2
[L- D* 2.0 ] 1 D
fh = + * ln
8 * D* L π r 0 * 2.0

38. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Drainable Porosity
μ = {0.0376 * (Ksat) 0.25} Chambal Varient (68%)
μ = {0.0386 * (Ksat) 0.25} Kota Varient (28%)

39. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Water Table Draw Down
20 cm in 3 days to control irrigation induced
salinity
Used for spacing calculation in transient
equation

40. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Average Drain Depth
Depending on soil properties, crop,
extent of soils salinity, gravity outlet
1-1.5 m below ground surface with
average of 1.2 m

41. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Simple Equations for Drain Spacing
For Chambal Soil Series
• Drain Spacing = 8.71 + 73.36 * Ksat0.5
For Kota Soil Series
• Drain Spacing = 13.61 + 67.92 * Ksat0.5

42. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Computer Program for Drain Spacing
For calculating drain spacing grid wise
• Auger hole Ksat dat
• Drainable porosity v/s Ksat
• Design Criteria

43. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Drain Spacing
Calculated for each grid (8.58 ha)
Geometric mean of calculated spacing (100-
150 ha area block)
Rounded to next multiple of 5 m
Range of spacing 35-85 m

44. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Drainage Coefficient
• Laterals 1.5 mm/day
• Collectors 3.0 mm/day
For pipe capacity calculation only

45. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Pipe Size
⎡ q *S *L*n ⎤
d =⎢
8 d
3
⎥
⎣ 0.31168 * i ⎦
1
2
Minimum pipe diameter
--- 72/80 mm

46. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Manning’s Roughness Coefficient & Grade
I.D. (mm) O.D. (mm) n Minimum Grade
(%)
72 80 0.015 0.10
88 100 0.015 0.10
144 160 0.016 0.09
178 200 0.017 0.08
258 294 0.018 0.07
315 355 0.019 0.06
401 455 0.019 0.05

47. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Length of Lateral
8/3 1/2
0.31168 * d * i
Lmax =
qd * S * n
Depends on physical limitation, farm size,
layout pattern etc.

48. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Minimum Soil Cover
Depends on soil conditions & depth of outlet
drain
Minimum soil cover of 0.90 m
Exceptional cases:
Up to 100 mm dia 0.60 m
160-455 mm dia 0.80 m

49. DESIGN OF SUBSURFACE DRAINAGE SYSTEMS
Design Criteria for SSD in Chambal Command Area
Envelope Requirement
Clay % Envelope
Requirement
>40 Not required
30-40 & SAR >8 Required
<30 Required
Pipe grade >0.4% --- not required

50. Design of SUBSURFACE DRAINAGE SYSTEMS

51. Design of SUBSURFACE DRAINAGE SYSTEMS

52. Outlet Conditions

53. Computer Aided Design Procedure

54. Computer
Aided
Design
Procedure

55. SSD Layout System
Parallel
Perpendicular

56. Position of Outlet
Field Drain
Carrier Drain
Main Drain

57. Minimum Permissible Clearance for
SSD Outlet
Depth of Base Flow Allowance for Free Depth to SSD Outlet
(db) Sedimentation Board Invert
(ds) (df)
Less than 65 cm 20 cm 15 cm SDBE+db+df
Min 45 cm & Max. 85 cm
More than 65 cm 20 cm Nil SDBE+db

58. Drainage Material
Up to 100 mm corrugated PVC pipes were available
Smooth Wall Rigid Pipes were used

59. Drainage Material
Plant set up at Kota for
Corrugated PVC pipes of 80, 100,
160, 200, 294, 355 and 455 mm
dia.
At Sangli 80-160 mm PVC & HDPE
as well as double wall corrugated
pipes up to 315 mm are produced
Envelope Material

60. SSD Installation
Excavation of trench
Laying of Pipe on the grade
Backfilling of the trench
Restoration of ROW
Manual

61. SSD Installation
Manual Excavator
Grade Control ???????

62. SSD Installation
Laser

63. SSD Installation
Laser Excavator

64. SSD Installation
Bulldozer-Plow

65. SSD Installation
Drain Laying Plow

66. SSD Installation
Drain Laying Plow

67. SSD Installation
Drain Laying Plow

68. SSD Installation
Drain Laying Plow

69. SSD Installation
Chain Trencher

70. SSD Installation
Chain Trencher

71. SSD Installation

72. SSD Installation
Chain Trencher

73. SSD Installation
V Plow

74. SSD Installation
V Plow

75. SSD Installation

76. SSD Installation

77. SSD Installation

78. SSD Installation
Import of Drain
Laying Equipments
Right of Way
Crop Compensation
Irrigation Shut Off

79. SSD Installation
Physical progress achieved
S.No. SSD installation method
at RAJAD
1 Manual installation 50 m/day with 20 labours
100 - 150 m/day per
2 Installation using excavator
excavator
Installed using a trenchless 4000 - 6000 m/day per
3
drain laying plow plow
1000 - 2000 m/day per
4 Installation using a trencher
trencher
About 2500 km of pipe installed in CCA

80. Supervision, Inspection and Quality Control
Preparation of Contract Document
Specification of Drainage Material &
Installation
Development of Contractors – national,
international

81. Human Resources Development
•Post Graduation in Drainage Engineering
•National & international Drainage Courses
•Use of Computers, Total Station, EM 38, GIS etc.
•Several workshops, seminars, awareness camps etc.
Assistance of International/National
Experts and Local/GOR Staff
People Participation
Subsidy
Coordination with State Government
Maintenance

82. Subsurface Drainage Installation in Chambal Command,
Rajasthan
Project Area installed Year
(ha)
Small Test Sites 410 1991-1993
Large Test Sites 1,010 1993-1994
Pre-CON/1 700 1995-1996
(Training Phase)
CON/1 10,671 1996-1999
Areas with Patchy 2,134 1997-1999
Salinity
Total 14,925 1991-1999

83. Pre Monsoon - 93

84. Post Monsoon - 93

85. Yield 0 q/ha ECe 19.2 dS/m

86. Yield 9.45 q/ha ECe 11.3 dS/m

87. Yield 12.8 q/ha ECe 10.4 dS/m

88. Yield 25.2 q/ha ECe 5.1 dS/m

89. Yield 34.1 q/ha ECe 2.7 dS/m

90. Yield 43.0 q/ha ECe 2.36 dS/m

91. Yield 0 q/ha ECe 19.2 dS/m Yield 9.45 q/ha ECe 11.3 dS/m Yield 12.8 q/ha ECe 10.4 dS/m
Yield 25.2 q/ha ECe 5.1 dS/m Yield 34.1 q/ha ECe 2.7 dS/m Yield 43.0 q/ha ECe 2.36 dS/m

92. IMPACT OF SUBSURFACE DRAINAGE
Soil Salinity Reclamation
• Continuous reduction in the salinity in the upper
15 cm depth.
• For the lower depths salinity levels increased
during first 3 years then salinity levels declined.
• Over a period of 5 years, the salinity level reduced
to below 4 dS/m
• After SSD salinity reclamation could be achieved
in 2 to 3 years for about 60% areas & within 3 to
4 years for 90-95% of the affected areas.
• About 5-10% of the affected area could take more
than 4 years for satisfactory reclamation

93. Crop Yield in Saline & Waterlogged areas and
non-saline & non-waterlogged areas
in the Chambal Command Area of Rajasthan.
Crop Crop Yield (Quintals/ha)
Saline Non-saline /
/waterlogged Non waterlogged
Wheat 17.0 34.0
Mustard 6.1 14.7
Paddy 17.0 29.0
Soybean 10.2 21.8
Berseem 360.0 520.0
Sugarcane na 567.5

94. Relationship between
Soybean Yield and Water table Depth
Average Water Soybean Relative Yield
Table Depth (cm) Yield (t/ha) (%)
80.0 2.18 100
70.0 1.93 88
59.6 1.69 77
50.0 1.44 66
40.0 1.20 55

95. Water Table Control
A drainage rate of 1.5 mm/day (an equivalent
water table draw down of 20 cm from soil
surface in three days) was considered
adequate to maintain a favorable salt balance.
Field observations since SSD installation in
various test sites have indicated that a water
table draw down of 20-40 cm in three days is
achievable.

96. Water Table Control
The water table control has an added positive
impact in advancing soil trafficability
conditions (tilth) by 6-10 days after a rainfall
or irrigation event, thereby allowing farmers
more time for farming operations
Good tilth conditions also provide a further
benefit, namely an opportunity to save fuel in
machinery operations.

97. Crop Performance
Increase in Crop Yield
The average increase in the crop yield in
SSD test sites compared with non-SSD
sites was about
• 56 percent for soybean and
• 55 percent for wheat.
Farmers have also reported
improvements in the quality and quantity
of produce, particularly vegetables.

98. Relationship with Soybean Yield,
Water Table depth and Soil Salinity
The analysis showed that soybean yield
was independent of the water table when
its depth was greater than 80 cm below
ground surface. The yield decreased as
the water table depth approached soil
surface.
The average optimum desirable water
table depth during growth season of
soybean is 80 cm for the CCA conditions.

99. Relationship with Soybean Yield,
Water Table depth and Soil Salinity
Monitoring at RAJAD indicated that an
average water table draw down of 20 – 40
cm within three days was achieved.
The majority of the drain flow rates from
these sites ranged from 1-4 mm per day.
The relationship between soybean yield
and soil salinity showed that crop yield is
independent of soil salinity, upto a
threshold ECe value of 4.1 dS/m. Beyond
that, the yield decreases.

100. Increase in Cropping Intensity
Water table control and salinity reclamation
in the test sites significantly alleviated
these constraints, which resulted in a 20-25
percent reduction in the amount of fallow
land in the Kharif season, and 5-6 percent
reduction in fallow during the Rabi season.
The pre-SSD cropping intensity was 150-
160 percent and the post – SSD cropping
intensity was 170-185 percent. The
cropping intensity is projected to further
increase.

101. POSITIVE IMPACTS OF
SUBSURFACE DRAINAGE
S.No. Impact Improvement
1. Salinity reclamation
I. Soils with EC 4-8 dS/m 2-3 years to achieve
II. Soils with EC 8-16dS/m 3-4 years to achieve
III. Soils with EC>16 dS/m > 4 years to achieve
2. Water table control 20-40 cm draw down
in 3-4 days
3. Soil trafficability Advanced by 6-10
days

102. POSITIVE IMPACTS OF
SUBSURFACE DRAINAGE
S.No. Impact Improvement
4. Crop Yield 56 % increase in
soybean;
55 % increase in
wheat yields
5. Cropping intensity Increased from 150-
160 percent to 170-
185 percent

103. Economics of Subsurface Drainage
As per economic and financial analysis of SSD
Assuming
• capital cost of SSD of RS. 34,250 per ha,
• using a discount rate of 12 percent and
• assuming that benefits would accrue from the
entire SSD installed area,
• the economic benefits of SSD for a 30 year life
expectancy were calculated as follows.
Benefit/cost ratio : 2.6
Net present value (NPV) per ha : Rs.54,900

104. The internal rate of return (IRR) = 28 %.
This relates to a 2.4 times return over the
market rate of interest that a farmer would
have to pay, if it was to be fully financed by
the farmer.
The above analysis indicated that SSD is a
cost effective method to reclaim
waterlogged and saline lands in the CCA.
This system can be replicated in other areas
of Rajasthan and India.

105. THANK YOU

106. Selection of Reclamation Technology

107. Selection of Reclamation Technology

108. Selection of Reclamation Technology

111. Relationship between
Soybean yield and Soil Salinity
Average ECe (dS/m) Soybean Relative Yield
for the 0-30 cm Yield (t/ha) (%)
Soil Depth
4.1 1.81 100
6.0 1.60 88
8.0 1.39 77
10.0 1.17 65