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By Mohamed Mustafa Abbas Mokhtar
AA tthheessiiss ssuubbmmiitttteedd iinn ppaarrttiiaall ffuullffiillllmmeenntt ffoorr tthhee rreeqquuiirreemmeenntt ooff tthhee ddeeggrreeee ooff
MMAASSTTEERR OOFF SSCCIIEENNCCEE IInn
Supervised by: Dr. Adil Mohamed ElKhidir
brought to you by COREView metadata, citation and similar papers at core.ac.uk
provided by KhartoumSpace

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Mother,
Father,
Wife,
Son,
Brothers, and
To all those who helped me in this research in one way or
another.
4
Acknowledgment
I am greatly indebted to my supervisor Dr. Adil Mohamed El-
Khidir for initiating this research and teaching me the basics of scientific
research. I wish to express my gratitude to him. His patience, keen
supervision and expert advice are gratefully acknowledged.
Deep appreciation is extended to His Excellency the Minister of Irrigation
and Water Resources Engineer Kamal Ali Mohamed for lending hands to
overcome all the difficulties.
staff, and civil engineering department, University of Khartoum for their
valuable support.
I would like to express my great thanks to all those who helped me,
specially my parents and brother Abd El-Rahman Hamid El-Fadil for his
technical assistance in English language.
Finally, I would like to thank Ministry of Irrigation and Water
Resources for giving me this opportunity to do my postgraduate study in
water resources engineering and finalizing my study. I am highly indebted
to the technical Minister's office staffs who take the responsibility of the
whole works during my study.
5
Abstract
Automation is used to simplify and reduce or replace the decision-
making process of the operators, and to implement a decision. It has
increasingly been used to improve the effectiveness and to reduce the cost of
water supply operations.
The purposes of thesis is to set a daily basis operation program for
'Rewina' canal system, the `program includes the irrigation schedules for crops,
irrigation depth, daily areas to be irrigated and quantities of water flows passing
through irrigation structures.
Thesis applied (theoretically) automation on the irrigation system, which
includes input data (monitored by sensors), that transmitted by
telecommunication system to the central control room, which will be analyzed
to determine the total areas to be irrigated on daily basis, discharges required
and the number of structures to be operated to pass the required discharges. The
input data includes field moisture contents, upstream and downstream water
levels besides the initial position(s) of gate(s) for each irrigation structure. The
output data includes the final position(s) of gate(s) for each irrigation structure,
which will be transmitted by telecommunication system from the central control
room to the field level for execution, by the motor erected in each gate.
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Abbreviations
BL Bed Level
CMS Central Monitoring System
EIT Environmental Information Technology
FSL Full Supply Level
LPS liter per second
8
SCP Societe du Canal de Provence ( )
TBL Top Bed Level
U/S Upstream Water Level
VHF Very High Frequency
WAN Wide Area Network
WFC Water Flow Control
Dedication ii
Acknowledgement iii
Abstract iv
Abbreviation viii
1-3 Irrigation in Gezira Scheme 4
1-4 Automation 5
Chapter-II Study Case ('Rewina' Canal System
Gezira Scheme)
Irrigation System
3-4-1 Fundamental Rules on Irrigation Water
Management 47
3-4-4 Water Losses 48
3-5-1 Sequential 49
3-5-2 Simultaneous 49
3-5-3 Selected 50
3-7 Data Telemetry and Transmission Systems 51
3-8 General Sensors Considerations 51
3-9 Control Gate Openings 52
3-10 Automatic Gate Control System 53
3-11 Water Level Sensors 53
3-12 Flow Rate Sensors 55
3-13 Gate Position Sensors 57
3-14 Soil Moisture Sensors 57
11
3-18 Equipment and Operating of Dynamic Regulation 60
3-18.1 Data Acquisition 61
3-18.2 Data Transmission 61
3-19-1 Opening and Closing 61
3-19-2 Check Gate 62
3-19-3 Opening Setting 62
3-20 Operating Software 63
3-21-1 Hardware 64
3-21-2 Software 65
Canal
4-2 Project Telecommunication System 69
4-3 Mechanism of Gate Opening 69
12
Chapter-V Conclusions and Recommendations
5-2 Recommendations 82
Annex No. (2)
Annex No. (3)
'Tables No. (3.13 - 3.14 - 3.15 - 3.6) Daily irrigated areas' 86
Annex No. (4)
'Some Photos for Devices used in Automatic Irrigation System' 86
Annex No. (5)
13
14
1.1 The Nile Water:
River Nile is one of the largest rivers in the world and life is directly
dependant upon it in the Sudan. It represents a link between different cultures,
ecological systems and different climates. The length of the Nile is 6,700 km
with a basin of 3.0 million km2 equal to 10% of Africa total area. Nile River
water passes through ten African countries Sudan – Egypt – Ethiopia – Eritrea
– Democratic Republic of Congo – Uganda – Kenya – Rwanda – Burundi –
Tanzania. The annual average of White Nile supply at Khartoum is estimated at
27 Milliard cubic meters (Mcm) and the natural supply of the Blue Nile at the
same point in addition to its two tributaries Dinder and Rahad is 54 Mcm. As
for Atbara River, the natural annual supply is 12 Mcm. Thus, the total annual
supply of the River Nile along with its tributaries at the middle of Sudan is 93
Mcm; however, the average annual supply of the River Nile at Aswan is
estimated at 84 Mcm.
1.2 Sudan Water Consumption:
The current rates of consumption for Nile tributaries (White Nile, Blue
Nile, and Atbara River) and the Main Nile are shown in Table (1.1). The
evaporation losses that take place at dams such as Roseries, Sennar, and Girba
are shown in Table (1.2). In addition, other uses for Nile water such as drinking
15
water for human, animals and the industrial sector are shown Table (1.3). The
total Sudan consumption is 15.530 Milliard m3 at mid Sudan equivalent to 14
Milliard m3 at Aswan dam.
Table (1.1): Sudan water consumption from the Nile system (Year 2002)
River Potential
Arable Area
(Million Fd)
Irrigated Area
(Million Fd)
N.A*: Not Available
Reference MOIWR Records
River Scheme Evaporation Losses (Million m3)
Blue Nile Rosaries Dam
Human (Urban and Rural) 280
Animal 740
Others 60
Total 1080
Reference MOIWR Records
Sudan is a large country in terms of area and climatic diversity. The
northern part is divided between Sahara and Semi-Sahara except the areas that
extending with the Nile. Rainfall rates ranges from zero in the north to 1000
mm in the far south. River Nile is the most important water resources in Sudan.
With regard to the schemes that aim at raising water supply by reducing
water losses in the swamps in the south, the annual loss rate is estimated to be
36 Milliard cubic meters. There are joint future projects between Sudan and
Egypt to save some of this amount. Potential benefit from these projects is
estimated at four Milliard cubic meters at the first stage for Jungile canal and 7
Milliard cubic meters from Bahr Al-Gazal basin project and 7 Milliard cubic
meters from Subatt project, the completion of these project will contribute to
the agricultural expansion in the future.
Sudan exploited only 15.530 Milliard cubic meters from his quota,
which is 20.5 Milliard cubic meters. Also, there is a future plan to utilize the 5
Milliard cubic meters of the Nile water through the heightening of Roseries
dam, setting up Kenana and Rahad canals (second phase), the pumps projects
on the Blue Nile and rehabilitation of current irrigation projects.
17
1.3 Gezira Scheme:
The Gezira irrigation Scheme lies between the Blue and White Nile rivers
south of Khartoum, and is fed principally by gravity irrigation from Sennar dam on the
Blue Nile. It has grown from the original scheme cultivating 300,000 fd to present
irrigation area of 2.1 million fd (about 882,000 ha, one feddan (fd) = 0.42 ha). The
climatic conditions are favorable to year-round cultivation, and the physical properties
of the impermeable clay soils show a tendency to water logging, which badly depress
the yields. Despite sixty-five years of irrigation, salinity is not a problem with the
exception of some fringe areas on drier zones near Khartoum. Blue Nile water is silt-
laden during the flood season (MOIWR magazine 2000).
The Sennar diversion dam built in 1925 regulates the flow of the Blue Nile.
The Gezira scheme was designed in the 1920's after prolonged experiments had been
carried out on a prototype scale. It was designed with the main objective of producing
cotton, a single cash crop. It was thus a non-perennial scheme with monoculture. Other
crops were initially grown to provide food for the tenant farmers, and to help in the
maintenance of soil fertility. Cotton, wheat, groundnut and sorghum are now cultivated
in a fifth-course rotation, including fallow (MOIWR magazine 2000).
The main, branch and major canals are designed as regime conveyance
channels. The minor canals are designed for storing water continuously flowing from
the major canals at night. The rough rules of thumb developed for the operation of the
scheme of such a large scale were the result of insufficient knowledge about the crop
requirements under Gezira soil and climatic conditions. According to the design
principle, the nominal flow in AbuXX is 5,000 m3/ day.
Crop intensification, expansion of the system, breakdown of the
communication system, and insufficiently funded maintenance critically resulted in
18
improper use of the system and inadequate control (MOIWR magazine, 2001). Due to
the deterioration of the movable weirs and their sensitivity to the fluctuating water
levels in the major canals, it become difficult to maintain the indented discharge into
the minor canals (MOIWR magazine, 2001).
The imposition of discipline and the re-institution of the old regulations may be
counter-productive especially during the summer rains, which disturb any pre-arranged
schedule. In this period, management consisted of day-to-day decision, with proper
field drainage deserving high priority (Saeed Mohamed Farah, 2000).
The field efficiency in the Gezira is estimated at about 75%, assuming usual
definition of crop water requirements, which exclude the field losses, and the overall
efficiency is 70% (MOIWR magazine, 2000). This value is the highest found in
surface irrigation project due to the nature of the soil (MOIWR magazine, 2000). The
high clay content of the soils in the Gezira plain and the design of the distribution
systems are the two main reasons for this high efficiency (MOIWR magazine, 2000).
If the major and minor canals are clean from silt and weed, there would be an
equitable water distribution.
1.4 Irrigation in Gezira Scheme:
Irrigation water for the Gezira scheme is diverted from the Blue Nile at Sennar
dam. The Blue Nile water hydrology, suitability, and the quality for irrigation are
excellent and overall availability of water to the project from Sudan's share of the Nile
waters is adequate for the needs.
The distribution system serving 1.10 million feddans in Gezira and about 1.0
million in Managil, comprises 260 km of main canals, 588 km of branch canals, 1601
km of major canals, and 7835 km of minor canals.
The irrigation system adopted in Gezira scheme consists of straight minor
canals with length 1420 m from main canals. These sub-canals are barreled and the
distance between each one is constant (280 m). Each minor-canal gets its water
through a gate equipped by pipe leading to the sub-canal. The minor-canal also divided
to Abu-XXs that run in a straight line with length of 1400 m and it stops before
reaching the next minor-canal.
The rectangulars of 90 feddans that are located between two sub-canals and
two Abu-XX are known as the ‘Blocks’, each one of these blocks is divided to smaller
parts and irrigated by small tributaries branching from Abu-XXs and known as Abu-
VIs.
At the beginning of operation of the scheme, the canals were basically designed
to irrigate limited areas planted by cotton, where the gate-keeper was responsible for
controlling the irrigation process, release the water from Abu-XX for seven days on
schedule base. During this period, the farmers of the upper part of the block will be
enabled to take enough water to irrigate. Then the chance is given to the farmers of the
lower part of the same block and thus cotton could be irrigated every two weeks with
water depth reaching 10 cm.
21
1.5 Automation:
Canal automation refers to closed – loop control in which a gate change its
position /setting in response to water level, flow rate or pressure because that level
/rate/ pressure is different from the intended target value. Closed loop’ means that the
action is performed without any human intervention .The automation may be
performed through hydraulic, electrical, electronic or a combination of these, means.
As it eliminates uncertainties and inadequacies of human interventions, automation of
some degree is acknowledged as an efficient means to simplify operation, increase the
reliability and flexibility of deliveries and reduce operational water losses.
1.6 Scope of Work:
1. To set a daily basis operation program for 'Rewina' canal system in
Kab-Elgiddad sub-division of Gezira scheme. The program includes the
irrigation schedules for crops, irrigation depth, daily areas to be
irrigated and quantities of water flows passing through irrigation
structures.
2. This operation program has been used as a base towards the automation
of 'Rewina' canal system.
3. Automation of canal system requires input data to be transmitted by
telecommunication system to the central control room. Input data
include field moisture contents, upstream and downstream water levels
besides the initial position of gate(s) for each irrigation structure. The
output data such as the final position of gate(s) for each structure will
be sent from the central control room, by telecommunication system, to
the considered irrigation structure for execution.
22
23
2.1 Location:
Sudan extends between latitude 40 and 220 North and longitude 220 and 380
East with an area of 2.5 millions km2 approximately. Zones north of 140 latitude
regarded as dry areas and totally dependent on the River Nile for Agriculture. Sudan
also is one of the tropical countries that characterized by its hot climate and there is no
vast difference between its season in term of temperature. The average annual
temperature is about 300, and the average annual rainfall is 400 mm.
Kab El-Giddad sub-division is located in the north of Gezira scheme between
longitude 320 42/ - 330 05/ East, and latitude 140 45/ - 150 15/ North (Fig.2.1). The total
irrigated area of Kab El-Giddad sub-division is 161,000 feddan, where area irrigated
by Rewina major canal is 6,100 feddan. Rewina major canal branched from the
western-north branch at 22 kilometer, which comes from main canal of Gezira scheme
at 156 kilometer.
Source: MIWR, 1978, Nile Water Study, Sudan
25
2.2 Water Supplies:
The Blue Nile is the source of the water supply for the Gezira Scheme. The
river is known for its marked seasonal and annual variations. It has an average annual
flow of 50-milliard m3 and contributes about 68% to the yield of the Nile. The seasonal
variation of its discharge ranges from over 10,000 m3/s at the peak of a high flood to
60 m3/s in a very low year. Analysis of water quality shows that the Blue Nile water is
suitable for irrigation.
2.3 Cropping Patterns:
The total area irrigated under study is 6100 feddan, where the area of holding
for each farmer is 20 feddan, and the area of 'hawasha' is 4 feddan.
From Table (2.1), the design factor (F) has been found as follows:
F= 3.46*106/ (6100 * 31 * irrigation efficiency) (2-1)
Where,
The factor 3.46 is the maximum irrigated water requirement, which occur in month
October, (Million m3/month)
6100: irrigated study area (feddans)
31: number of days of month October
Overall irrigation efficiency is 0.85,
Resulted design factor (F) is 21.5 m3/fed./day
26
Table (2.1): Seasonal crop water requirements data and Monthly Irrigation Requirements.
E T crop m3/fed
Crop Jan Feb Jun July Aug Sep Oct Nov Dec
G.N (1220F) 407 700 868 924 681 156
Dura (1220F) 598 910 936 434
Wheat (1220F) 564 134 147 652 806
Cotton (1220F) 634 377 169 464 714 976 892 774
Total IWR (Million
Source: (Farbrother, 1976)
Table (2.2): Irrigation seasons for grown crops for 'Rewina' canal system.
T I M E S P A N
Crop Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Ground
Nuts
(G.N)
Dura
Wheat
Fallow
Cotton
27
G.N
20 %
Dura
20 %
Wheat
20 %
Fallow
20 %
Cotton
20 %
G.N
Minor Canal No. of
28
Table (2.6) Irrigation Scheduling for Cotton:
Irrigation Interval (Days) Irrigated Area (Fd) Discharge (m3/day)
27 45.2 18,080
24 50.8 20,320
16 76.2 30,480
13 93.8 37,520
13 93.8 37,520
12 101.7 40,680
13 93.8 37,520
15 81.3 32,520
15 81.3 32,520
15 81.3 32,520
21 58.1 23,240
21 58.1 23,240
Irrigation Interval (Days) Irrigated Area (Fd) Discharge (m3/day)
20 61 24,400
18 67.8 27,120
16 76.2 30,480
15 81.3 32,520
13 93.8 37,520
13 93.8 37,520
14 87.1 34,840
15 81.3 32,520
20 61 24,400
Irrigation Interval (Days) Irrigated Area (Fd) Discharge (m3/day)
24 50.8 32,320
17 71.8 28,720
15 81.3 32,520
15 81.3 32,520
21 58.1 23,240
Irrigation Interval (Days) Irrigated Area (Fd) Discharge (m3/day)
22 55.5 22,200
16 76.2 30,480
14 87.1 34,840
12 101.7 40,680
14 87.1 34,840
12 101.7 40,680
18 67.8 27,120
1
Table (2.13): Daily GROUND NUT Irrigated Areas (in Feddan) for Different Minors, Irrigation period (1st Jun - 22nd Oct)
Minor 1
Minor 2
Minor 3
Minor 4
Minor 5
Minor 6
Minor 7
Minor 8
Minor 9
Minor 10
Minor 11
Minor 12
Jun-1 38 19 4 2 38 19 4 3 38 19 4 4 27 13 21 5 39 18 4 6 39 18 4 7 34 18 9 8 12 37 12 9 37 14 10 10 37 14 10 11 11 11 36 3 12 36 25 13 36 25 14 5 32 24 15 32 29 16 3 25 17 15 1 17 39 12 6 4 18 9 26 22 4 19 5 26 26 4 20 14 17 26 4 21 38 19 10.8 22 38 19 10.8 23 38 19 10.8
2
1 Minor 2
Minor 3
Minor 4
Minor 5
Minor 6
Minor 7
Minor 8
Minor 9
Minor 10
Minor 11
Minor 12
25 39 18 10.8 26 39 18 10.8 27 6.8 18 37 6 28 12 37 14 4.8 29 37 14 16.8 30 6.4 14 36 11.4 Jul-1 3 36 28.8 2 36 31.8 3 3.4 32 18.2 2.8 11.4 4 16 30 5.8 15 1 5 39 22 2.8 4 6 34.6 15.4 13.8 4 7 11.8 26 26 4 8 11.4 26 26 4 9 38 19 19.2 10 38 19 19.2 11 38 19 19.2 12 27 13 36.2 13 39 18 19.2 14 12.2 18 37 9 15 18 37 14 7.2 16 12 37 14 13.2 17 8.8 14 36 17.4 18 36 32 8.2 19 36 32 8.2
3
20 4.6 32 12.4 0.6 25.6 1 21 6.6 39 24 2.6 4 Minor
1 Minor 2
Minor 3
Minor 4
Minor 5
Minor 6
Minor 7
Minor 8
Minor 9
Minor 10
Minor 11
Minor 12
22 31.4 26 14.8 4 23 20.2 26 26 4 24 25.6 21.4 26 4 25 38 19 24.3 26 38 19 24.3 27 38 19 24.3 28 27 13 39 2.3 29 33.1 18 30.2 30 18 37 14 12.3 31 18 37 14 12.3 Aug-1 9.7 34.8 14 22.8 2 9 36 32 4.3 3 36 32 13.3 4 13.6 32 34.7 1 5 2.3 30 23.3 21.7 4 6 30 26 21.3 4 7 25.3 26 26 4 8 21.7 7.4 22.7 26 4…