During the year of 2008-09 Department of Agriculture, Government
of Himachal Pradesh, decided to launch an ambitious project namely
“Diversification of Agriculture through Micro
Irrigation and Related Infrastructure” which is now a flag ship State Sponsored Scheme and is being
implemented with name of “Pandit
Deen Dayal Kisan Bagwan Samriddhi Yojan Part II”. The project was submitted to NABARD for consideration under Rural
Infrastructure Development Fund (RIDF) – XIV.
During the appraisal it was found that proposed project was
based on very preliminary and tentative estimate. One of the serious flaws in
the proposal was lack of design of sprinklers systems which are to be
implemented in varying topography of Himachal Pradesh. There are large
variations in topography especially slope parameters in Outer- sub Himalayan
Zone (Siwaliks), Lower Himalayan Zone, Higher Himalayan Zone and Tibetian or
Tethys Himalayan Zone. Hence, Hydraulic and Structural Design had to be devised
for different topographic conditions.
A technical team in a personnel capacity and on voluntarily
basis was associated comprising following resource persons :
Late
Er. Y. P. Thakur
|
Executive Engineer,
Division Shimla
Agriculture Department, Government of
HP
|
Chairman
|
Er.
Rajesh Yadav
|
Manager, NABARD
Himachal
Regional office, Shimla
|
Mission Leader
|
Er.
Aswani Bhardwaj
|
Assistant
Engineer,
Division Shimla,
Agriculture Department, Government of HP
|
Member
|
Er.
Sunil Kumar Kesary
|
Area Manager
HARVEL
Irrigations Private Limited
Himachal
Preadesh
|
Member
|
About the
Project
Sprinkler Irrigation System : 15 Models of the systems were developed which are based on topography of
three irrigation systems situated in district Kangra and Shimla for 5 field
categories of 0.5 ha, 1 Ha, 2 Ha, 3 Ha and 4 Ha.. In the Kangra district two
irrigation systems situated in Dehra and Baijnath Tehsil are representing plain
and mid hill area while third one has been taken from Rohru Tehsil of Shimla
district representing high hill area of the State. It is assumed that the water
source would be either made available though tank irrigation and operating head
would be met out from gravitational head of higher contour level or by
providing booster pumps of maximum operating head of 35 m. Further in some
areas where shallow wells, shallow tubewells, deep tubewells would be feasible,
same would be utilised as source of water and water would be lifted by suitable
capacity of the pumping machineries. For the systems situated at higher
elevation than the available surface water, the low and medium lift systems
would be installed as source augmentation structures. However, the first
priority would be given to gravitational operation systems. Total area to
be covered was 19987 Ha with a project cost of Rs.7,941.40 lakh.
The main components proposed under sprinkler irrigation systems are as under :
Main Pipe : All pipes taken in the DPR are HDPE pipes of
different diameters conforming to IS 4984. The grade of the pipe taken is of
PE-63 up to 4 Kg/sqcm pressure class and PE-80 for pressure class of 6, 8, 10
Kg/sqcm. The main pipeline carries water from the tanks/pumping unit
to the various parts of the field and supply water to the portable lateral
through hydrants. Main line pipes are proposed to be buried so that they do not
come in way of other agricultural operations.
Lateral Pipe :
Lateral lines carry water from the main line to sprinklers or nozzles. Lateral
lines proposed of HDPE pipes with quick couplings conforming to IS 14151-I
Marked) to withstand pressure up to 3.2 Kg/sqcm. It is proposed to be portable.
Length lateral pipes are taken in 3 m and 6 m. Each length has quick couplings.
All couplings are provided rubber gaskets in female portion, which tightens the
coupling and makes it, leak proof.
Sprinkler heads/Nozzles :
Rotating head sprinkler nozzle having discharge capacity of 0.48 liters per
second at a operating head of 1.76 Kg/sqcm has been taken in the DPR. The
through range of the sprinkler is 12 m. The nozzle size of the sprinkler is
5.159 mm. The utilization rate of the sprinkler head is 2.4 cm/hr and 1.2 cm/hr
at spacing of 6 x 12m and 12 x 12 m, respectively.
Riser Pipe : The riser pipe connects the
rotating sprinkler head to the lateral. The pipe diameter is taken 20 mm with
standard pipe threads and height 75 cm.
Hydrant : Brick masonry structure of size 0.45 x 0.45 x 0.375 m
is proposed at 40 to 50 interval on main line. 50 mm hydrant including GI riser
pipe, 63 mm PP ball valve, 63 mm connecting nipple, plain concrete grouting GI
tee, connecting riser pipe with sub main including complete set of fitting
etc.
Accessories : P/F of PP ball valve of different diameter, air
release valve of 1 and 2” size, coupled bend, duly coupled tee, duly coupled
end cap, sprinkler attachments, Foot batten assembly etc., have been incorporated
in the estimate.
Drip irrigation Systems : Items of development under drip system are PVC pipe
(63 and 75 mm) and 4 kg/sqcm, 12 mm lateral of LLDPE, flow control valve 75 mm,
flush valve PP 63 mm, screen filter having capacity 10 cum/hr, by pass assembly
(1.5” x 1.5”), Ventury (1.5’’) with manifold alonwith fittings and accessories.
50 Drip irrigation systems are proposed on pilot basis. The
unit area of the field is taken 0.4 ha and spacing of the crop is taken 1 x 1
m. The estimated cost of this model is Rs.42300/- and per ha cost is
Rs.106,000/-. Total coverage of this system was 20 Ha only with project cost of Rs.21.20 lakh.
Ponds/ Water Harvesting Structures : 15 models of the 6510 ponds/water storage structures
have been proposed. 3 models of Kuchha pond, 3 models of Ponds lined with UV
stabilised multilayered core laminated sheet of 200 GSM, 3 models of ponds with
poly and brick lining and 6 models of RCC have been proposed. The capacity of
the pond vary from 50000 liters to 600,000 liters with estimated cost of
Rs.26,000 to Rs.490,000. The Unit costs of the pond/tanks vary from Rs.0.18 to
Rs.3.60 per liters with average cost of Rs.0.86 per liter. Total cost of
tanks/ponds was Rs.4711.20 lakh.
Low and Medium Lift Irrigation System : 500 small and 500 medium lift
irrigation systems are proposed without distribution system. The water would be
lifted from the perennial stream through rising main with the help of pumping
machinery. Other previsions taken are pump house (medium lift), delivery tank, SOP
and LS provision of source management. The estimated cost of low lift and
medium lift is Rs.1.25 lakh and Rs.3.40 lakh, respectively. The design
discharges have been taken 3 lps and 5 lps, against the total head of 35.85 m
and 63.28 m, respectively. Total
cost of low lift system was Rs.625.00 lakh Similarly total cost of medium lift system was
Rs.1700.00 lakh.
Shallow and Deep Tubewells : 490 shallow tubewells (STW) and 10
deep tubewells (DTW) have been proposed as source augmentation structures.
Shallow Tubewells are proposed with depth of 35 m and deep tubewells with 70 m
depth having single assembly size of 150 mm and 200 mm, respectively. The
estimated cost of STW and DTW is Rs.2.0 lakh and Rs.8.0 lakh which is only for
drilling and development of tubewell. Total cost of shallow tubewell was Rs.980.00 lakh.
Shallow open wells : 500 shallow well of 2.45
internal diameter and 8 m depth made of RR masonry (0.35 thickness) are
proposed as source augmentation structures where sufficient ground water would
be available. The estimated cost of the borewell is Rs.1.10 lakh. Total cost of shallow open wells was Rs.550.00 lakh.
Pumping Machinery : 7510 number of
pumping machinery has been proposed for different models and capacities ranging
from 1.0 HP to 15 HP. The per HP cost of different models varies from Rs.5920
to Rs28040 including cost of accessories with average cost of Rs.4430. Total cost of pumping machineries was Rs.999.06
lakh.
Technical parameters
A) General
Design : Parameters
for the systems requirements for the 5 models
are as under:
S. No.
|
Particular
|
Unit
|
Quantity/ Design
Parameter
|
||||
Model
1
|
Model 2
|
Model
3
|
Model 4
|
Model
5
|
|||
1
|
Total CCA
|
Ha
|
0.50
|
1
|
2
|
3
|
4
|
2
|
Sprinkler
Nozzle discharge at presure of
|
lps
|
0.48
|
0.48
|
0.48
|
0.48
|
0.48
|
3
|
Total No. sprinkler nozzles that will operate at a time
from each Hydrant
|
Nos.
|
2
|
4
|
4
|
5
|
7
|
4
|
No.
of Hydrants that will operate from each sub Main line
|
Nos.
|
1
|
1
|
2
|
2
|
2
|
5
|
No. of sub main lines that will operate in each tapping
point
|
Nos.
|
1
|
1
|
1
|
1
|
1
|
6
|
No.
of the tapping points that will operate at a time
|
Nos.
|
1
|
1
|
1
|
1
|
1
|
7
|
Sprinkler spacing
|
m x m
|
12 x 12
|
12 x 12
|
12 x 12
|
12 x 12
|
12 x 12
|
8
|
Effective
area covered by each sprinkler nozzle
|
sqm
|
144.00
|
144.00
|
144.00
|
144.00
|
144.00
|
9
|
Total discharge required to operate the system
|
lps
|
0.96
|
1.92
|
3.84
|
4.80
|
6.72
|
10
|
Total
No. of sprinkler nozzles that will operate at a time in whole system
|
Nos.
|
2
|
4
|
8
|
10
|
14
|
11
|
Total area covered by sprinkler system at a time
|
Ha
|
0.0288
|
0.06
|
0.12
|
0.14
|
0.2016
|
12
|
Total
number of the shifts required in whole system
|
Nos.
|
18.00
|
18
|
18
|
21
|
20
|
13
|
Duration of each shift
|
min
|
30.00
|
30
|
30
|
30
|
30
|
14
|
Total
operating time
|
hour
|
9.00
|
9
|
9
|
10.5
|
10
|
15
|
Taking 10 hours of operation a day
|
day
|
1
|
1
|
1
|
1
|
1
|
16
|
Frequency
of irrigation
|
day
|
3
|
3
|
3
|
3
|
3
|
17
|
Consumptive use
|
mm/day
|
4
|
4
|
4
|
4
|
4
|
B) Hydraulic and
structural design of the lateral :
Model wise hydraulic design of the lateral is based on the design discharge as
per above general design table and frictional losses has been calculated on the
basis of Modified Hazen William Formula and multiple outlet factor. The
operating head is calculated on the basis of minimum operating pressure of 1.75
kg per sqcm for operating sprinkler, height of riser is taken 0.9 m and frictional losses in the maximum length of
the lateral pipe for given topography. Accordingly it is observed that the
operating head required is varies from 19 m to 22 m, hence pressure class of
the HDPE pipe is taken 3.2 kg per sqcm in all the cases.
C) Hydraulic and
structural design of the Main Pipes :
Model wise hydraulic design of the main is based on the design discharge as per
above general design table and frictional losses has been calculated on the
basis of Modified Hazen William Formula. The minimum and maximum head is
adjusted with operating head required for lateral pipe to be jointed at each
hydrant points by manipulating diameter of main pipes keeping maximum velocity
of 3.08 m/s. All the pressure such as maximum gravitational head at any
interval of hydrants (i.e cumulative static pressure) due to change in
altitude, hammer pressure due to stopping of hydrants during shifting operation
and if the sufficient head is not available then the head developed by the
booster pumps are considered while hydraulic designing of main pipes.
Accordingly, pressure class of the pipe has been selected on the basis of
maximum head possible between the hydrants i.e sum of the cumulative static
head and hammer pressure. Hence, 4, 6, 8 and 10 Kg per sqcm having grade PE-63
and PE-80 and diameter vary from 40 mm to 110 mm has been incorporated in
different models.
Sample
Model Design
Model Project Name : Micro
Irrigation Scheme at village Bhamnoli in GP Bhamnoli in Tehsil Rohru District
Shimla (HP)
The maximum internal
pressure likely to come under worst circumstances is taken equal to the sum of
full static pressure and water hammer pressure
P = Ps + Ph
|
Where,
P = Total internal maximum pressure,
Ps = Static Pressure, and
Ph = Water Hammer Pressure
Hoop Tension = P X d / ( 2 x t )
|
Where,
d = diameter of the pipe
and
t = thickness
of the pipe
Hoop tension should not
exceed the Safe allowable tensile stress of the pipe material
Coefficient
of Hydraulic Capacity for HDPE Pipe : 1.00 (AS PER
MODIFIED HAZEN WILLIAM'S FORMULA)
Optimum
Velocity Range
: 0.3 to 1.8 m/s but maximum 2.0 m/s
Operating
Head of Nozzle : 1.76 kg/sqcm (18.13 m of water)
Height
of the riser pipe :
0.90 m
Part I : Hydraulic
Design of Main / Sub-Main and Lateral Pipe
S.
No.
|
Line
|
RDs
|
|
Length (m)
|
Required Discharge (lps)
|
Diameter (mm)
|
Velocity (m/s)
|
Frictional Losses (m)
|
|
|
From
|
To
|
From
|
To
|
|
|
|
|
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
1
|
Tank
|
A
|
0
|
50
|
50
|
6.72
|
67.2
|
1.89
|
2.57
|
|
Add 25 m head to be
provided by the booster pump
|
||||||||
2
|
A
|
B
|
50
|
100
|
50
|
6.72
|
56.5
|
2.68
|
5.91
|
3
|
B
|
C
|
100
|
150
|
50
|
6.72
|
53.5
|
2.99
|
7.68
|
4
|
C
|
D
|
150
|
200
|
50
|
6.72
|
53.5
|
2.99
|
7.68
|
5
|
D
|
E
|
200
|
250
|
50
|
6.72
|
52.9
|
3.06
|
8.11
|
6
|
E
|
F
|
250
|
320
|
70
|
6.72
|
52.9
|
3.06
|
11.35
|
7
|
F
|
G
|
320
|
370
|
50
|
6.72
|
50.6
|
3.34
|
10.04
|
8
|
G
|
H
|
370
|
420
|
50
|
6.72
|
50.6
|
3.34
|
10.04
|
S.
No.
|
Line
|
Hydraulic Level
(m)
|
Ground Level (m)
|
Residual Head (m)
|
Diff. Static Head (m)
|
Cum Static Head (m)
|
Pressure Break Provision
|
||
|
From
|
To
|
Upper End
|
Lower End
|
|
|
|
|
|
1
|
2
|
3
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
1
|
Tank
|
A
|
1000.06
|
997.49
|
975.06
|
22.43
|
25.00
|
25.00
|
|
2
|
A
|
B
|
997.49
|
991.59
|
964.98
|
26.61
|
10.08
|
35.08
|
|
3
|
B
|
C
|
991.59
|
983.90
|
954.90
|
29.00
|
10.08
|
45.16
|
|
4
|
C
|
D
|
983.90
|
976.22
|
947.30
|
28.92
|
7.60
|
52.76
|
|
5
|
D
|
E
|
976.22
|
968.11
|
939.70
|
28.41
|
7.60
|
60.36
|
|
6
|
E
|
F
|
968.11
|
956.76
|
929.06
|
27.70
|
10.64
|
71.00
|
|
7
|
F
|
G
|
956.76
|
946.71
|
921.46
|
25.25
|
7.60
|
78.60
|
|
8
|
G
|
H
|
946.71
|
936.67
|
913.86
|
22.81
|
7.60
|
86.20
|
|
S.
No.
|
Line
|
Dia of Lateral
|
No. of Sprinkler
|
Velocity
|
Multiple Outlet Factor
|
Losses
|
Operating Head Required
|
Pressure Class of the pipe
|
|
|
From
|
To
|
|
|
|
|
|
|
|
1
|
2
|
3
|
19
|
20
|
21
|
22
|
23
|
24
|
25
|
1
|
Tank
|
A
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
2
|
A
|
B
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
3
|
B
|
C
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
4
|
C
|
D
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
5
|
D
|
E
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
6
|
E
|
F
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
7
|
F
|
G
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
8
|
G
|
H
|
53.5
|
7
|
1.49
|
0.4304
|
1.58
|
20.61
|
3.2 Kg/sqcm
|
Part II : Structural
Design of the Main and Sub-main (HDPE PIPE)
Max Hammer Pressure, Ph (max) = 1433 V/ SQRT ( 1 + ( Ew / Ep ) * ( d / t ))
|
Where,
V =
Velocity of Water
Ew = Modulus
of elasticity of water ) : 2100000 KN/sqm ( KPa )
Ep = Modulus
of elasticity of HDPE pipe ) :
667000 KN/sqm ( KPa )
d = Diameter of pipe
t = thickness of pipe
S.
No.
|
Line
|
Length (m)
|
Dia (mm)
|
Velocity (m/s)
|
Cum Static Head (m)
|
Water Hammer Pressure (m)
|
Field Test Pressure Which shall be greatest of
|
||
From
|
To
|
1.5 x Col. 28
|
Col. 28 &
Col 29
|
||||||
1
|
2
|
3
|
25
|
26
|
27
|
28
|
29
|
30
|
31
|
1
|
Tank
|
A
|
50
|
67.2
|
1.89
|
25.00
|
1.23
|
37.50
|
26.23
|
2
|
A
|
B
|
50
|
56.5
|
2.68
|
35.08
|
1.74
|
52.62
|
36.82
|
3
|
B
|
C
|
50
|
53.5
|
2.99
|
45.16
|
2.40
|
67.74
|
47.56
|
4
|
C
|
D
|
50
|
53.5
|
2.99
|
52.76
|
2.40
|
79.14
|
55.16
|
5
|
D
|
E
|
50
|
52.9
|
3.06
|
60.36
|
2.81
|
90.54
|
63.17
|
6
|
E
|
F
|
70
|
52.9
|
3.06
|
71.00
|
2.81
|
106.50
|
73.81
|
7
|
F
|
G
|
50
|
50.6
|
3.34
|
78.60
|
3.44
|
117.90
|
82.04
|
8
|
G
|
H
|
50
|
50.6
|
3.34
|
86.20
|
3.44
|
129.30
|
89.64
|
S.
No.
|
Line
|
Max FTP of Col 30 and 31
|
Pressure Class of the HDPE Pipe
|
Dia of the pipe (mm)
|
Cum Length (m) of pipe of particular dia and
PR
|
|
From
|
To
|
|||||
1
|
2
|
3
|
32
|
33
|
34
|
35
|
1
|
Tank
|
A
|
37.50
|
4 Kg/sqcm
|
75.00
|
50.00
|
2
|
A
|
B
|
52.62
|
4 Kg/sqcm
|
63.00
|
50.00
|
3
|
B
|
C
|
67.74
|
6 Kg/sqcm
|
63.00
|
50.00
|
4
|
C
|
D
|
79.14
|
6 Kg/sqcm
|
63.00
|
100.00
|
5
|
D
|
E
|
90.54
|
8 Kg/sqcm
|
63.00
|
50.00
|
6
|
E
|
F
|
106.50
|
8 Kg/sqcm
|
63.00
|
120.00
|
7
|
F
|
G
|
117.90
|
10 Kg/sqcm
|
63.00
|
50.00
|
8
|
G
|
H
|
129.30
|
10 Kg/sqcm
|
63.00
|
100.00
|
Total
|
420.00
|
After incorporating all above technical and financial parameters
and the detailed estimates, cost of the DPR increased from Rs.143.51 crore to
Rs.198.08 crore. We are thankful to Officers and especially to then Hon’ble
Chief Minister of Himachal Pradesh for according approval within a very – very
short time i.e. within 2 days.
This project has now became "State
Sponsored Scheme" of Himachal Pradesh's Government and we are so lucky for
getting opportunity to formulate this flag-ship Project.
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