IE intro

1. Course Instructor
Engr. Ghulam Murtaza
MSc Water Resource & Irrigation Engineering
UET Taxila
BSc Civil Engineering
UET Taxila
Contact: Cell: 03005069389
Mail: gmurtaza18@gmail.com
Irrigation Engineering (CE-431)

2. Course Contents
 Introduction
 Definition and type of irrigation. Water Resource for
irrigation, surface water. Irrigation system of Pakistan
 Canal irrigation
 Elementary concept about canal head works,
selection of their site and layout, weirs and barrages,
various components and functions.
 Measures adopted to control silt entry into canals, silt
ejectors and excluders. Design of weirs on permeable
foundations, sheet piles and cut off walls. Design of
irrigation channels.
 Kennedy’s and Lacey’s Theories. Rational methods
for design of irrigation channels. Comparison of

3.  Canal head regulators, falls, flumes, canal
outlets. Cross drainage works: types and
functions.
 Canal lining: advantages and types.
 Maintenance of irrigation canals.
 Irrigated Agriculture
 Water requirements of crops, duty of irrigation
water.
 Delta of crops, consumptive use, estimation of
consumptive use, methods used for assessment
of irrigation water.
 Irrigation methods and practices.

4.  Soil survey and land classification
 Reservoirs
 Water logging and salinity:

5.  Text Book
“IRRIGATION ENGINEERING & HYDRAULIC
STRUCTURES” by “Santosh Kumar Garg”.
 Reference Books
1. Linslay, R.K. and Joseph, B.F. Water Resources
Engineering, McGraw Hill.
2. Siddiqui, Iqtidar H., Irrigation and Drainage
Engineering, Oxford University Press
3. Iqbal Ahmed, Irrigation Engineering and
Hydraulic Structures

6. Water Resources
Lecture # 1

7. Introduction
 Plants are living beings and do require water and
air for their survival, as do human beings require.
Their requirement of water varies with their type.
 Different types of plants require different
quantities of water, and at different times, till they
grow up completely.
 Water is normally supplied to these plants by
nature through direct rain or through the flood
waters of rivers which inundate large land areas
during floods.

8. Introduction
 Sometimes, there may be very heavy rains creating
serious floods and damaging the crops, and sometimes,
there may not be any rains at all, creating scarcity of
water for the crops. Thus, famine and scarcity conditions
are created.
 In his bid to control the nature, man discovered various
methods by which the water can be stored during the
periods of excess rainfall, and to use that stored water
during periods of ‘less rainfall’ or ‘no rainfall’. The art or
the science by which it is accomplished is generally
termed as irrigation.

9. Introduction
 Irrigation is an art of applying water to the land by
artificial means to fulfil the water requirements of
crops in areas specially where rainfall is
insufficient.

10. Sources of Water for Irrigation
The water supply for agriculture is from three main
sources
a) Rainfall
b) Surface water
c) Ground water

11. Need for Irrigation
 Arid Zones:
For such zone annual rainfall is less than 15"
and an irrigation system is necessary.
 Semi-Arid Zones:
In these areas, precipitation (annual rainfall)
ranges from 15"-30" and an irrigation system is
desirable.
 Humid Zone:
For these zones the annual rainfall is more
than 30".Therefore an irrigation system is beneficial.

12. Rainfall in Pakistan
 In Pakistan the mean annual rainfall ranges from less
than 4" in parts of the lower Indus region to more than
30" in the Northern foothills.
 Of this annual rainfall only a small portion makes any
useful or direct contribution of irrigation water
supplies.
 According to consultant experts of the World Bank the
figure ranges from1" to 17". The rest is either surface
runoff or addition to the ground water reservoir while
some is lost by evaporation.
 It is estimated that the present direct contribution to the
crops is 6 MAF per annum.

13. Surface Runoff
 Pakistan rivers carry the melting snow and rains from
the Northern hills down to the plains where they can be
used for irrigation.
 From mid-March to mid-July (When the monsoon
breaks) the river discharges derive mainly from
melting snow.
 From mid July to September rain water adds to the
volume

14. Ground Water
 After rainfall and surface water, ground water is the
most important water source for irrigation.
 In hilly areas this is in form of springs, wells, etc and
may be the only source for irrigation.
 Using ground water by sinking tube wells may
seem to be the direct and rapid way of meeting
immediate irrigation water requirements.
 However not all the available ground water may
be suitable for irrigation use.
 An estimated 41.6 MAF of groundwater is pumped
annually in Pakistan

15. Advantages of Irrigation
 Cooling the soil and atmosphere and thereby creating a
favorable environment especially for plants to grow.
 Irrigation helps in increasing crop yields, and hence, to
attain self-sufficiency in food.
 Optimum utilization of water is made possible by
irrigation.
 Cheaper power generation can be obtained from water
development projects primarily designed for irrigation
alone
 Development of irrigation facilities in an area helps in
extending the water supply in nearby villages and
towns, where other sources of water are not available
or are scarcely available.

16. Advantages of Irrigation
 Mixed Cropping is eliminated.
 Irrigation channels are generally provided with
embankments and inspection roads. These
inspection paths provide good roadways.
 larger irrigation canals can be used and developed
for navigation purposes.
 Washing out and diluting undesirable salts in the
soil.
 Softening the land for better tillage.

17. Disadvantages of Irrigation
 Irrigation may contribute in water pollution.
Seepage of nitrates, that have been applied to the
soil as fertilize, can pollute the ground water.
 Irrigation may result in colder and damper climate.
 Over-irrigation may lead to water-logging and may
reduce crop yields.
 Obtaining and supplying irrigation water is
complex and expensive in itself. Sometimes,
subsidized cheaper water has to be provided at the
cost of the government, which reduces revenue
returns.

18. Phases of Irrigation
Irrigation engineering consists of four phases
1. Storage and diversion.
2. Conveyance of irrigation water.
3. Distribution and application of irrigation water.
4. Drainage of excess water

19. Selection of Suitable Source for
Irrigation
The selection for suitable source for irrigation
depends on the following
 Reliability of the source
 Quantity of water available
 Quality of water

20. Types of Irrigation
Irrigation projects are classified as
 Direct irrigation method
 Storage irrigation method.

21. Types of Irrigation
Irrigation may broadly be classified into
1. Surface irrigation
2. Subsurface irrigation
1. Surface irrigation can be further classified into
1.1 Flow irrigation
1.2 Lift irrigation
2. Subsurface irrigation can be further classified into
2.1 Natural sub-irrigation
2.2 Artificial sub-irrigation

22. Types of Irrigation
1. Surface irrigation
1.1 Flow irrigation
When the water is available at a higher level, and it is
supplied to lower level, by the mere action of gravity, then
it is called Flow Irrigation.
1.2 Lift irrigation
if the water is lifted up by some mechanical or manual means,
such as by pumps, etc. and then supplied for irrigation, then it is
called Lift Irrigation.

23. Types of Irrigation
2. Subsurface irrigation
2.1 Natural sub-irrigation
When underground irrigation is achieved simply by
natural processes, without any additional extra efforts,
it is called natural sub-irrigation.
2.2 Artificial sub-irrigation
When a system of open jointed drains is artificially
laid below the soil, so as to supply water to the crops
by capillarity, then it is known as artificial sub-
irrigation

24. Techniques of Water Distribution in Farms
There are various, ways in which the irrigation water can be
applied to the fields. Their main classification is as follows
1. Free flooding
2. Border flooding
3. Check flooding
4. Basin flooding
5. Furrow irrigation method
6. Sprinkler irrigation method
7. Drip irrigation method

25. Techniques of Water Distribution in Farms
1. Free Flooding:
In this method, ditches are excavated in the field. Water from
these ditches, flows across the field. After the water leaves the
ditches, no attempt is made to control the flow by means of
levees, etc. Since the movement of water is not restricted, it is
sometimes called wild flooding.
Although the initial cost of land preparation is low, labour
requirements are usually high and water application efficiency is
also low. Wild flooding, is most suitable for close growing
crops particularly where the land is steep. Contour ditches called
laterals or subsidiary ditches, are generally spaced at about 20 to
50 meters apart, depending upon the slope, texture of soil, crops
to be grown .

26. Techniques of Water Distribution in Farms
2. Border flooding :
In this method, the land is divided into a number of
strips, separated by low levees called borders. The land
areas confined in each strip is of the order of 10 to 20
meters in width, and 100 to 400 meters in length. When
the advancing water reaches the lower end of the strip,
the supply of water to the strip is turned off.

27. Techniques of Water Distribution in Farms
A relationship between the discharge through the supply
ditch (Q), the average depth of water flowing over the
strip (y), the rate of infiltration of the soil (f), the area of
the land irrigated (A), and the approximate time required
to cover the given area with water (t), is given by the
equation

28. Techniques of Water Distribution in Farms
maximum area that can be irrigated with a supply ditch of
discharge Q and soil having infiltration capacity (f).

29. Techniques of Water Distribution in Farms
Example1.
Determine the time required to irrigate a strip of land of 0.04
hectares in area from a tube-well with a discharge of
0.02cumec. The infiltration capacity of the soil may be taken
as 5 cm/hr, and the average depth of flow on the field as
10cm.
Also determine the maximum area that can be irrigated from
this tube well.

30. Techniques of Water Distribution in Farms
Example1.

31. Techniques of Water Distribution in Farms
Example1.

32. Techniques of Water Distribution in Farms
Example1.

33. Techniques of Water Distribution in Farms
3. Check flooding
Check flooding is similar to ordinary flooding except
that the water is controlled by surrounding the check area
with low and flat levees. Levees are generally
constructed along the contours, having vertical interval
of about 5 to 10 cm. These levees are connected with
cross-levees at convenient places . The confined plot area
varies from 0.2 to 0.8 hectare

34. Techniques of Water Distribution in Farms
4. Basin flooding
This method is a special type of check flooding and is
adopted specially for orchard trees. One or more trees are
generally placed in the basin, and the surface is flooded as in
check method, by ditch water, as shown in Fig.

35. Techniques of Water Distribution in Farms
5. Furrow irrigation method
In Farrow irrigation method only one-fifth to one-half of the
land surface is wetted by water.

36. Techniques of Water Distribution in Farms
6. Sprinkler irrigation method
In this farm-water application method, water is applied to the
soil in the form of a spray through a network of pipes and
pumps. It is a kind of an artificial rain.

37. Techniques of Water Distribution in Farms
7. Drip irrigation method
In this method, water is slowly and directly applied to the root
zone of the plants, thereby minimizing the losses by
evaporation and percolation.

38. Indus Water Treaty
In 1947, when Punjab was divided between the two countries,
many of the canal head-works remained with India. The
division of Punjab thus created major problems for irrigation in
Pakistan.
On April 1, 1948, India stopped the supply of water to Pakistan
from every canal flowing from India to Pakistan.
Pakistan protested and India finally agreed on an interim
agreement on May 4, 1948.
Pakistan approached the World Bank in 1952 to help settle the
problem permanently. Finally in Ayub Khan's regime that an
agreement was signed between India and Pakistan in Sep.1960.
This agreement is known as the Indus Water Treaty

39. Indus Water Treaty
This treaty divided the use of rivers and canals between the
two countries.
 Pakistan obtained exclusive rights for the three Western
Rivers, namely Indus, Jhelum and Chenab.
 India retained rights to the three Eastern Rivers, namely
Ravi, Beas and Sutlej

40. Irrigation System in Pakistan
 Pakistan is situated in Arid Zone.
 The Indus basin receives less that 15" of rainfall in a year,
 with 30% of the area receiving even less than 10%.
 Agriculture therefore heavily depends on irrigation.
 The major rivers in Pakistan are the Indus, its left bank
tributaries are Jhelum, Chenab, Ravi and Satluj, and right
bank tributaries of Swat, Kunhar, Kabul and Kurram etc.
 The annual runoff of the Indus system of rivers is estimated
as 168 MAF (Million acre ft.)

41. Irrigation System in Pakistan
 Sukhur Barrage, Chushma Barrage, Rasool Barrage, Guddu
Barrage, Kotri Barrage , Head Sulemankee, Head Marala,
Head Rasool, Head Khanki, Head Bulloki etc. are
constructed for irrigation purposes.
 Besides it, a vast irrigation canal system was constructed in
1960, to transfer water of western rivers to the canal
systemof eastern rivers, Beas, Ravi and Satluj.

46. Indus River Basin:
Salient Features
 Catchment area of Indus is most unique in the sense that it
contains seven (7) of the world’s highest peaks after Mount
Everest. Among these include the K2 (28,253 ft), Nanga
Parbat (26,600 ft), Rakaposhi (25,552 ft) etc.;
 Further to above, seven(7) glaciers situated in the Indus
catchment are among the largest in the world, namely,
Siachin, Hispar, Biafo, Baltura, Baltoro, Barpu and
Hopper.

47. Salient Features of Main Rivers - Sutlej River
Origin Western Tibet in the Kailas Mountain range and near the source
of Rivers Indus, Ganges and Bramaputra
Length 960 miles/1536 Km
CatchmentArea 47,100 Sq.miles/75,369 Sq.km (70% in India)
Pakistan portion Flows into Pakistan (Punjab) near Ferozepur and eventually joins
Chenab 3 miles u/s Punjnad Barrage
Tributary Rivers Eight major tributaries (all except Rohi Nullah join Sutlej in
India)
Largest Tributary River Beas (290 miles/464km), catchment area (6,200
Sq.miles/9,920 Sq.km)
Dams on the River Bhakra, Nangal, Pong, Pandoh (all in India),
Barrages on River Rupar Barrage, Harike Barrage, Ferozepur Barrage (India),
Sulemanki & Islam in Pakistan

48. Salient Features of Main Rivers - Ravi River
Origin Originates from the lesser Himalayas Range in India
Length 550 miles/880 Km
CatchmentArea 15,600 Sq.miles/24,960Sq.km
Pakistan portion Runs almost along the Indo-Pak Border -15km d/s Madhopur to 20
miles u/s of Shahdara (58 miles)
Tributary Rivers Five major tributaries (Ujh, Bein, Basantar, Deg, Hudiara nullahs –
upper catchments lie in India)
Largest Tributary Deg Nullah (160 miles/256km), catchment area (456 Sq.miles/730
Sq.km)
Barrages on River Madhopur Headwork (India), Balloki & Sidhnai (Pakistan)

49. Salient Features of Main Rivers - Chenab
River
Origin -Forms at the confluence of streams Bhaga &
Chandra which join at a place called Tandi in Occupied
Jammu & Kashmir state.
-Upper most part is snow covered and forms the North East
part of Himachal Pradesh
-From Tandi to Akhnur the river traverses through high
mountains
Length 770 miles/1,232 Km
CatchmentArea 26,100 Sq.miles/41,760 Sq.km
Pakistan portion The river enters Pakistan a little over Head Marala with very
sharp changes in slope (130 ft/mile above Tandi reduced to 2
ft/mile close to Trimmu)

50. Salient Features of Main Rivers - Jhelum
River
LargestTributary Kishan Ganga/Neelumh (165 miles/264km), catchment
area (2,480 Sq.miles/3,968 Sq.km)
Barrages on River Mangla Dam, Rasul Barrage

51. Salient Features of Main Rivers - Indus River
Origin -One of the largest rivers of the world and the main river
of the Indus valley;
-Originates near lake Mansarowar on north of
Himalayas range in the mountain of Kailash Parbat in
Tibet at an elevation of 18,000 ft.;
Length 925 miles/1,489 Km above Tarbela
CatchmentArea 1,80,000 Sq.miles/2,88,000 Sq.km

53. Punjab
The public irrigation infrastructure in the Punjab consists of
 16 barrages
 2 siphons across major rivers
 12 link canals and 23 major canal systems over an
aggregate length of 34,500 km.
The whole irrigation infrastructure lies within the Indus Basin
System. It serves an area of 8.58 million hectares. In
addition, there are 135 surface drainage systems including
over 670 drains, with an aggregate length of about 6,600
km, which drain an area of about 5.79 million hectares,
within the 23 canal commands.

54. Sindh
 14 publicly owned canals system, which receive water
from three barrages across the River Indus. These
systems, with an aggregate length of 18,000 km of
canals, serve an area of about 5.38 million hectares.
 There are 13 existing surface drainage systems in
Sindh, which serve a total area of over 3.5 million
hectares and have an aggregate length of about 4,800
km.

55. KPK
 5 publicly owned irrigation systems in the Indus Basin,
which serve a total area of 0.34 million hectares. These
systems receive water from two headworks across River
Swat and Warsak Dam. In addition, there are six other canal
systems, which serve a total of 0.13 million hectares of
land.
 Also has over 200 canals called `civil canals`, which are
community or privately owned. These irrigate an aggregate
area of 0.83 million hectares.
 There are four surface drainage systems in KPK comprising
of 456 drains.
 These serve a total area of 0.37 million hectares.

56. Balochistan
 Balochistan has two canal systems, which receive
water from the Indus Basin System through Guddu
Barrage and Sukkur Barrage, located in Sindh. These
canal systems serve a total area of 0.33 million
hectares.
 Feeder Canal System, has been improved recently. In
addition, there are 431 independent publicly owned
small irrigation schemes, which serve 0.14 million
hectares. There are a few privately owned small
irrigation schemes too.

57. Groundwater usage for irrigation
 An estimated 41.6 MAF of groundwater is pumped
annually in Pakistan.
 According to a study, more than 90% of the extracted
groundwater is used for
 irrigation purposes. Groundwater reservoirs are
recharged from the rivers as
 well as the seepage losses from the canals,
watercourses, farm channels and the fields.