The document provides a report on field visits conducted to various irrigation projects in Nepal, including the Bagmati Irrigation Project, Khageri Irrigation Project, Narayani Lift Irrigation Project, and Gandak Barrage. Key details about each project are given such as location, command area, water sources, construction costs, and components from headworks to canal outlets. Observations from the field visits note the type of diversion structures, river training works, regulating structures, and issues around water losses and sedimentation. The projects play an important role in agriculture and the economy by facilitating irrigation over large command areas.

1. TRIBHUVAN UNIVERSITY
KHWOPA COLLEGE OF ENGINEERING
An undertaking of Bhaktapur Municipality
Libali, Bhaktapur
A
Report on: Irrigation and Drainage Engineering
Title: Field Visit Report on Different Irrigation Project
SUBMITTED BY: SUBMITTED TO:
Sushrut Gautam KCE074BCE089 Department of Civil Engineering
Swarnima Shrestha KCE074BCE090 Khwopa College of Engineering
Ujjwal Acharya KCE074BCE091 Libali, Bhaktapur
Umesh Bhatta KCE074BCE092
Date of Submission: 2077/11/21

2. i
PREFACE
A 4 days and 3 nights field visit to different irrigation projects namely Bagmati Irrigation Project,
Khageri Irrigation Project, Narayani Lift Khageri Irrigation Project and Gandak Barrage, different
transportation structures and Hetauda Cement Factory was organized by Khwopa College of
Engineering. The field visit was from Falgun 11 to Falgun 14, 2077 B.S. as per the curriculum of
IOE, Tribhuvan University. We were able to visit and see the different components of Irrigation
projects which helped us to grab the knowledge about them visually. It is our belief that the report
will serve to introduce about different Irrigation Project. For this I would like to show my gratitude
to Er. Ramesh Bala, HOD, Department of Civil Engineering, Khwopa College of Engineering and
all other who helped us directly and indirectly during our trip and field visit. We would like to extend
our gratitude to our friends who helped us to prepare this report and made our field visit unforgettable.
Sincerely
Sushrut Gautam
Swarnima Shrestha
Ujjwal Acharya
Umesh Bhatta
“Civil 074 CD Batch”

3. ii
ACKNOWLEDGEMENT
We must express our sincere gratitude towards Department of Civil Engineering, Khwopa College
of Engineering for organizing the field trip for Irrigation and Drainage Engineering. We must express
our deep sense of gratitude towards Head of Department, Er. Ramesh Bala sir for organizing the
trip. We are deeply indebted to Er. Naresh Suwal sir for sharing a part of his brain and for proper
guidance during field trip. We should like to thank Mr. Nirmal Kafle, Er. Anil Kasula and Er.
Bibek Shahi for properly guiding us in our field trip.
We must acknowledge our deep sense of gratitude to the staffs of Bagmati Irrigation Project, Khageri
Narayani Lift Irrigation Project, Gandak Barrage and Hetauda Cement Factory for providing us the
opportunity to visit the respective places. We must acknowledge our obligation to all the non-
teaching staff of the Field trip for making our work a success. Also, we wish to record our
appreciation to our friends for providing the inexpressible amount of support and guidance. We are
highly obliged to all the people who supported us directly and indirectly throughout the duration of
the field visit to the submission of this report. Thanks are due to our family and friends who supported
us on our field visit.

4. iii
ABSTRACT
This report deals with different Irrigation projects and their components. Irrigation engineering is a
field of engineering which would discuss the uses of irrigation in crop production and how new
principles and technologies can be used and applied for irrigational practices.
This report encompasses the valuable information about the Bagmati, Khageri and Narayani lift
irrigation projects of Nepal being based on the four days long field visit to the respective areas. This
report presents the general information of those irrigation projects of Nepal and even a detailed
evaluation related to their history, background, and present status. On the other hand, this report is a
detailed description of the respective irrigation projects on the basis of their construction cost,
affected districts, problems, type of diversion head works, river training works adopted, regulating
structures provided as well methods being adopted to control and mitigate different problems that are
mainly responsible for the reduction in the efficiency of their performance.
Bagmati irrigation project was initially run as multipurpose project. Its construction was aided by
UNDP, Debt Relief Fund (Japan), and is now being in function by loan from Saudi Arabia. Major
headwork components include under sluice portion, divide wall, canal head regulator, canal portion,
and river training work such as earthen guide banks. Also, a provision of flood control is done by
construction of bypass. According to field survey of 1999, there has been increase in 34.98% of total
production in and around the irrigation project area which concludes that there is significantly good
impact of the project and effectively running very smoothly till date.
Khageri irrigation project, which is one of the oldest irrigation projects of Nepal, is located in
Chitwan district of Nepal and irrigates 3900 ha land. Major headwork includes under sluice portion,
divide wall, canal head regulator, canal portion, and river training work such as Chut blocks, stone
pitching in the banks. Initially it was designed to irrigate 3900ha but only 2400ha were being irrigated
before IMPT and main cause being lack of maintenance, lack of water sources, pollution degrading
quality of water in the river, etc. However, it is still working with efficiency of 30-36%.
Narayani lift irrigation project involves lifting of water to height of about 22m by two sets of pumps.
It was completed in 1985 at cost of NRs. 470,000,000 financed by ADB. Since this project is highly
costly with high power consumption of Rs. 10,800 per hour, operation and maintenance cost of
Rs.70-80 million, there is difficulty in maintaining balance in cost effectiveness. However, it plays
major role in rice production there.
Keywords: Irrigation, Lift, Mitigate, Headwork, Efficiency, Diversion

5. iv
Table of Contents
PREFACE .......................................................................................................................................... i
ACKNOWLEDGEMENT ............................................................................................................... ii
ABSTRACT...................................................................................................................................... iii
1. INTRODUCTION......................................................................................................................1
1.1 Background of Irrigation in Nepal....................................................................................1
2. OBJECTIVES.............................................................................................................................1
3. METHODOLOGY.....................................................................................................................2
4.STUDYAREA……………………………………………..………………………………………2
4.1 BAGMATI IRRIGATION PROJECT..........................................................................2
4.2 KHAGERI IRRIGATION SYSTEM............................................................................4
4.3 NARAYANI LIFT IRRIGATION......................................................................................5
4.4 GANDAK BARRAGE..........................................................................................................6
5. OBSERVATIONS AND ANALYSIS .......................................................................................8
5.1 OBSERVATIONS ON BAGMATI IRRIGATION PROJECT ..........................................8
5.2 OBSERVATIONS ON KHAGERI IRRIGATION PROJECT.........................................11
5.3 OBSERVATION ON NARAYANI LIFT IRRIGATION..................................................13
5.4 OBSERVATION ON GANDAK BARRAGE .....................................................................16
6. CONCLUSION AND DISCUSSION.........................................................................................19
7.RECOMMENDATION................................................................................................................20
8. REFERENCES ............................................................................................................................20

6. 1
1. INTRODUCTION
1.1Background of Irrigation in Nepal
The adoption of irrigation of Nepal is not a new thing, as it appears to be, because sufficient proofs
are available in history of Nepal, which confirm that irrigation was being practiced not only during of
RANAS, SHAHI but even during the period of Lichhivi. The first national irrigation project in Nepal is
Chandra Nahar during period of Chandra Samsher in Saptari district (1965 B.S) irrigating command area
of 10000 hectare and still in operation. In field work various parts headworks, intake structures, canals,
cross drainage structures etc. were carefully observed, analyzed, and studied in detail.
More than 81% people are engaged in agriculture in Nepal. Agriculture is the main source of income in
Nepal. As per record of Government of Nepal, Ministry of Finance, 2054/55, more than 40% of national
income comes from agriculture in Nepal but the growth rate in agriculture is only 2.4%. Since the living
standard of people is directly related to the income of people in any country, there is an urgency to maintain
and enhance the income of country like Nepal. In case of our country, a major concern has to be given in
the field of agriculture because of the fact that major portion of the national income comes from agriculture.
In order to extract major yields from agriculture and in turn enhance the economy of our country, it is
important that we improve the agriculture system by a better and more scientific method of irrigation apart
from use of improved seeds, fertilizers etc.
The agriculture can be the source of employment to many people of our country that is currently jobless if
we can utilize almost all the available arable lands. It is believed that more than 50% of the land of our
country is used only for seasonal agricultural products. Agriculture Perspective Plan has stressed the role
of agriculture in generation of employment opportunities and improving the living standard of people. This
plan has also defined irrigation as a strategic input and has prescribed the conjunctive use of water in Terai
region. As the agricultural sector contributes a significant amount to the national income, the change in
national income is a direct reflection of the change in agricultural production.
If we can arrange better irrigation facilities in our country, the national income can be increased
significantly. When national income increases, the per capita income will also increase. This is an effective
indicator of economic growth. Thus, it is essential to analyze the parameter of agricultural growth. In this
connection, irrigation is one of the most important inputs to increase the agricultural product particularly
in the following two grounds. Firstly, we can increase the agricultural product in the cultivated land with
irrigation by enhancing the efficiency of rest auxiliary inputs. And, secondly, we can extensively cultivate
the uncultivated agricultural land providing irrigational national facilities.
However there has not been much significant steps taken place in Nepal. Out total 2.18-million-hectare
irrigable land in Nepal, 1.74 million ha is in the plains of Terai region and rest 0.44 million is situated in
the valleys of the hill. Out of these potential irrigable areas, just 1.766 million ha has been provided
irrigation and out of which some 1.06 million ha. are already developed (i.e., provided with infrastructure)
for irrigation. Of the latter figure, however, only about 71 percent is actually irrigated. That leaves some
29 percent of the developed command area that could be brought under irrigation with relative ease, in
addition to the nearly 700,000 ha, yet to be developed for irrigation. Areas covered by surface and ground
water irrigation are 854,000 and 206,000 ha respectively and representing 80.6 percent and 19.4 percent
respectively of the total irrigated area.
2. OBJECTIVES
i. To find out the type of diversion headwork
ii. To get familiar with the components from headwork to canal outlet
iii. To know about the provisions for high flooding
iv. To gather information about the regulating structures and cross drainage structures
v. To know about the water losses during conveyance
vi. To know about total command area, canal design discharge and major water sources
vii. To know about the past disasters if any
viii. To determine the socio-economic benefits of the projects in local and national scale

7. 2
3. METHODOLOGY
The main methodology we followed for the accomplishment of our objectives of the field trip was
following the explanations made by the related personnel working on respective irrigation projects.
Similarly, for the study, the brochures and the information boards were used. Photographs of the location
were taken and the important points were noted. Similarly, the different literatures were also followed for
the reliability of data. In the same way, internet records were utilized to gather information regarding
different factors of the projects.
4. STUDY AREA
1) Bagmati Irrigation Project
2) Khageri irrigation project
3) Narayani lift irrigation
4) Gandak Barrage
4.1 BAGMATI IRRIGATION PROJECT
Location: Karmaiya, Sarlahi
Establishment: 2050/04/05
Geological Coordinates: 27° 07'53" N and 85° 28'59” E
Facilitated District: Sarlahi, Rautahat, Bara, Mahottari
Total Command Area: 122000 hectares
Canal Design Discharge: 8000m3
/sec
Design Flood: 100-year return period
Major Water Source: Bagmati River
Construction Cost: NRs. 37,809,610.25 (estimated)
Maintenance Cost: 1.5 to 2 crores yearly
Owner: Ministry of Water Resources, Department of Irrigation, Government of Nepal
Financier: Government of Nepal
Sedimentation Problem: Siltation problem is high due to Deforestation and Mobile Boundary.
Diversion Headwork: Barrage
Components from Headwork to Canal Outlet: Barrage, under sluices, Divide Wall, Fish ladder,
Canal Head Regulator, Silt ejector
Provision in case of High Flooding:
i. The system can withstand 10000 cumecs of water.
ii. Hydraulic and Structural Design is adopted.
River Training Work Adopted: Guide Banks, Marginal Bunds, Pitched Island, Bandalling
Regulating Structure provided: Head Regulators
Cross Drainage Structure: Syphon Super passage, Aqueduct
Major Causes of Water Losses:
i. Seepage losses
ii. High Percolation
iii. Not closing of gate properly
Major Crops in Command Area: Paddy, Rahar Dal
Future Project: Sunkoshi-Marine Diversion Project

8. 3
Fig: Bagmati Irrigation Project
Bagmati irrigation project is located in the central region of Nepal and diverts water from Bagmati River
through diversion barrage structure located at Karmaiya, Sarlahi district. This project is initially
conceptualized as a multipurpose project to develop irrigation facilities over an irrigable area of 122000ha
of Bara, Rautahat, Sarlahi, and Mahottari district and to generate electricity of 140 MW by constructing a
117m high dam. Bagmati irrigation project was commenced as Sunkoshi terai project and the study was
conducted by UNDP and FAO FROM 1967 TO 1972 A.D. The government then started the construction
by the usage of self-resources and equipment’s after which the constructed was economically aided by
UNDP and Debt Relief Fund (Japan) and is now being in function by the loan from Saudi Development
Fund. The main objectives, the project carries are to provide the efficient irrigation facilities to 37000ha
agricultural lands which thereby work as the aid to the socio-economic uplifting of the living standard of
the farmers.
This irrigation project has the following properties:
Barrage
Design discharge=8000m3
/sec
By pass channel=2500m3
/sec
Total=10500m3
/sec
Length=403.50m
Duty=1.34lt/sec
No. of gate=30 nos. (9*3m)
No. of fish ladder=2nos. (1.5*4m)
No. of under sluice=6nos. (9*4m)
Eastern H/R
Maximum discharge=64.4m3/
sec
No. of gate=7nos.
Western H/R
Maximum discharge=48.4m3
/sec
No. of gate=5nos.(4x2m)

9. 4
4.2 KHAGERI IRRIGATION SYSTEM
Location: Chitwan
Establishment: 2026B.S.
Geological Coordinates: 27°37'57"N and 84°29'21" E
Facilitated District: West Chitwan
Total Command Area: 3900 hectares
Canal Design Discharge: 9-14m3
/sec
Major Water Source: Khageri River
Construction Cost: NRs. 7465619 (estimated)
Maintenance Cost: 2 crores yearly
No. of gate: 2 nos.
Owner: Ministry of Water Resources, Department of Irrigation, Government of Nepal
Financier: Government of Nepal
Sedimentation Problem: Siltation problem is little.
Diversion Headwork: Barrage
Components from Headwork to Canal Outlet: Barrage, Divide Wall, Canal Head Regulator
River Training Work Adopted: Chute Blocks, Marginal Bunds
Regulating Structure provided: Head Regulators
Cross Drainage Structure: Aqueduct
Major Causes of Water Losses:
i. Seepage losses
ii. Not closing of gate properly
Major Crops in Command Area: Maize, Paddy
Length of main canal: 22+650km
Length of Branch canal: 55km
Length of tertiary canal: 100km
Fig: Khageri Irrigation Project

10. 5
Khageri Irrigation System (KHIS) is one of the oldest agency managed irrigation systems located in
Chitwan District in Western Nepal. It provides irrigation to about 3,900 ha of land in the West Chitwan.
The construction of the system was initiated in 2017 B. S. and completed in 2024 B. S. at the cost of Rs
7.6 million. The physical structures of the system include a diversion barrage, 23-km long main canal, 55
km of branch canals and 100-km long tertiary canals. About 7 km of the main canal passes through the
buffer zone of Royal Chitwan National Park, where many lakes have been formed due to regular canal
flow. These lakes serve as water reservoirs and augment the water supply to the main canal besides regular
supply obtained from Khageri River.
4.3 NARAYANI LIFT IRRIGATION
Location: Narayangadh, Chitwan
Establishment: 2034B.S.
Geological Coordinates: 27°40'44"N and 84°26'12"E
Facilitated Areas: Bharatpur, Mangalpur, Phulbari, Shivanagar and Gitanagar VDC’s
Total Command Area: 4700 hectares
Canal Design Discharge: 240000lpm
Major Water Source: Narayani River
Construction Cost: NRs. 42500000 IGO
Financial Aid: ADB
Sedimentation Problem: Siltation problem is high.
Diversion Headwork: Barrage
Regulating Structure provided: Head Regulators
Major Crops in Command Area: Maize, Paddy
Reduced Level: 272m
Number of Pumps: A (5 nos.) + B (4 nos.) = 9 nos.
Working Month: Asar to Asoj
Working Hours: 16 hours
Electricity Consumption: 4000000 units = NRs. 15000000
Maintenance cost: NRs. 5crore yearly
Pump level: 40m above head: Pump A (22m) + Pump B (18m)
Gravity System: 70%
Lift System: 30%
The Narayani lift irrigation project is the second largest irrigation project after Eastern Rapti Irrigation
project (5,966 ha) of Chitwan district. This irrigation system was designed to irrigate 8,600 ha of land in
West Chitwan, including 3,900 ha by the Khageri Irrigation System. The area directly under the Narayani
irrigation scheme was 4,700 ha but now it is reduced to 3500 ha (Central irrigation development board,
Bharatpur, 2012). The lift was also supposed to augment the Panchakanya irrigation system (600 ha) of the
district. It directly pumps water from a reservoir built along the Narayani River.

11. 6
Fig: Narayani Lift Khageri Irrigation Project
NLIP has two main canals i.e., B and C. Canal B covers 2400 ha of parts of Bharatpur, Mangalpur, Phulbari,
Shivanagar and Gitanagar VDCs. Its length is 19 km. It has 20 branch canals and 87 tertiaries, the total
length which is 17.95 km and 82.73 km respectively. Its maximum water flow capacity of canal B is 7.8
m3
/sec. Canal C covers 2,300 ha land of Bharatpur Municipality. But water is not sufficient for 2,300 ha of
land due to the low capacity of Pump house B. It is 10.5 km long. Day by day the areas of C canal are
reducing due to urbanization and low capacity of Pump house B. It has altogether 15 branches and 97
tertiaries. Total length of branch canals and tertiaries is 20.8 km and 61.50 km, respectively. Its maximum
water flow capacity is 3.2 m3
/sec. Total length of drain of B and C canal is 34.6 km.
4.4 GANDAK BARRAGE
Location: Nawalpur, Indo-Nepal Border
Establishment: 1969 A.D.
Facilitated District: Nawalpur, Parasi
Total Command Area: 14.04 lakh hectare (India) and 0.44 lakh hectare (Nepal)
Canal Design Discharge:
Major Water Source: Gandaki River
Owner: Government of India and Government of Nepal
Diversion Headwork: Barrage
No. of Gates: 36 (18 Nepal and 18 India)

12. 7
Canals: NEC and WEC
Components from Headwork to Canal Outlet: Canal Head Regulator, Barrage, Silt ejector,
under sluices, Divide wall
River Training Work Adopted: Marginal Bund, Guide banks
Regulating Structure provided: Canal Head Regulator, Distributary Head Regulator
Cross Drainage Structure: Aqueduct, Syphon Super passage
Major Causes of Water Losses: Not closing of door properly, Seepage losses.
Major Crops in Command Area: Maize, Paddy, Wheat, Potatoes
Negative Impacts:
i. Regular Flooding
ii. Water logging
iii. Riverbank erosion
iv. Change in river course
Fig: Gandak Barrage
The Gandak Project at Valmikinagar intercepts water of a catchment area of 37,410 km, which is mostly
in Nepal and partly in India. An agreement was signed on 4 December 1959 between the governments of
Nepal and of India on the Gandak Irrigation and Power Project. It encompassed the construction of a
barrage, canal head regulators and other appurtenant works about 33 m (108 ft) below the existing Triveni
Canal Head Regulator. The agreement was modified in 1964 for the protection of Nepal’s riparian rights.
Basically, there is an agreed share of water for ‘western canal system including a power station in Nepal
and eastern canal system. As a part of this bilateral agreement, the Gandak Barrage, a part of Gandak
Project, was built in 1968-69 over the Gandak river for providing irrigation to Nepal, Uttar Pradesh and
Bihar. The Eastern Gandak Canal Project was taken up in 1960 and Main Canal system was completed in
1975.

13. 8
5. OBSERVATIONS AND ANALYSIS
The different information that we have collected in order to meet our objectives of the trip are collected
and analyzed. The description of them is as follows:
5.1 OBSERVATIONS ON BAGMATI IRRIGATION PROJECT
5.1.1 Under Sluice Portion
The under sluices are the openings provided at the base of the weir or barrage. These openings are provided
with adjustable gates. Normally, the gates are kept closed. The crest of the under-under sluice portion of
the weir is kept at a lower level (1 ~ 1.5 m) than the crest of the normal portion of the weir. The suspended
silt goes on depositing in front of the canal head regulator. When the silt deposition becomes appreciable
the gates are opened and the deposited silt is loosened with an agitator mounting on a boat. The muddy
water flows towards the downstream through the scouring sluices. The gates are then closed. But, at the
period of flood, the gates are kept opened.
5.1.2 Divide Wall
Fig: Divide Wall
The divide wall is a masonry or concrete wall constructed at right angle to the axis of the weir. The divide
wall extends on the upstream side beyond the beginning of the canal head regulator, and on the downstream
side, it extends up to the end of the loose protection of the under-sluices. In this irrigation project, cement
concrete divide wall observed.
5.1.3 Canal Head Regulator
Fig: Canal Head Regulator

14. 9
A structure which is constructed at the head of the canal to regulate flow of water is known as canal head
regulator. It consists of a number of piers which divide the total width of the canal into a number of spans
which are known as bays. The piers consist of number tiers on which the adjustable gates are placed. The
gates are operated form the top by suitable mechanical device. A platform is provided on the top of the
piers for the facility of operating the gates. Again, some piers are constructed on the downstream side of
the canal head to support the roadway.
5.1.4 Canal Portion
Fig: Main canal
The main canal is lined with cement concrete and was in functioning state. The distributary canal was not
working and the components of the canal were on the deteriorated state because of rusting.
5.1.5 Disaster history and risks
The highest flood was recorded on 4th
and 5th
Shrawan, 2050 which took the life of two Chinese workers
and destroyed the divide walls and other structures of the headwork. The upstream of this irrigation project
is prone to landslides and flood due to steep slopes and degraded watersheds. Also, there is the problem of
sedimentation problem for which Bagmati River Basin improvement Programs are being conducted.
5.1.6 Provision for high flood
Bypass of capacity 2500m3
/sec is provided for the emergency case especially for high flood periods to
protect the barrage from effects of high discharge.
5.1.7 River protection

15. 10
5.1.8 Socio-economic benefits of project: The irrigation has positive impact on agricultural
production, farm income and employment. But the extent of impact depends on various factors such as
cropping intensity, crop type, management of irrigation facilities, farming technology etc. Therefore, the
impact may vary by place to place and project to project. The primary data collected within the outside the
Bagmati Irrigation Project command area that could determine the impact of irrigation in following ways:
Table 1: Effect of Irrigation on Total Output
Crops
Total output (kg)
Without
Irrigation
With
Irrigation
Change in
Total
% Change
Paddy (Rain
Seasons Crops)
1542.40 2182.40 640.00 41.49
Wheat (Winter
Crops)
1323.00 1625.05 302.05 22.83
Maize (Winter
Crops)
673.75 887.81 214.06 31.77
Other (Winter
Crops)
248.36 417.22 168.86 67.99
Total 5112.48 1324.98 34.98
Source: Field Survey, 1999. Note: Other crops include Mustard, Dal etc.
From Table 1, we come to know that there is 34.98% increase in the total production with irrigation facility.
Among the four cultivated crops, mustard and oil-seeds have been found more affected by irrigation. The
productions of mustard and oil-seeds have increased by 67.99% in irrigated land compared to their
production in non-irrigated land. The production of paddy, on the other hand, has also increase by 41.49
percent. Because of the availability irrigation facility, there has been possible to cultivate some of the
agricultural lands three times a year. Thus, Bagmati Irrigation Project has increased the total production of
farmers significantly.
5.1.9 Effect of Irrigation on Farm Income
The agricultural production has been increased in irrigated land as reflected in Table 2. To get farm income,
the annual physical productions of both irrigation and non-irrigated lands have been converted into
monetary term.
Crops
Farm income
Without
Irrigation
With
Irrigation
Change in
Total
% Change
Paddy (Rain
Seasons Crops)
7021.00 14885.5 7864.50 112.014
Wheat (Winter
Crops)
7413.0 10783.5 3370.50 45.46
Maize (Winter
Crops)
5143.00 7742.00 2599.00 50.53
Other (Winter
Crops)
3769.00 7643.00 3874.00 102.78
Total 23346.00 41054.00 17708.00 75.85
Table 2: Effect of Irrigation on Farm Income

16. 11
5.2 OBSERVATIONS ON KHAGERI IRRIGATION PROJECT
5.2.1 Under Sluice Structure
The under sluices are the openings provided at the base of the weir or barrage. These openings are provided
with adjustable gates. When the silt deposition becomes appreciable the gates are opened and the deposited
silt is loosened with an agitator mounting on a boat. The muddy water flows towards the downstream
through the scouring sluices. The gates are then closed. But, at the period of flood, the gates are kept
opened.
5.2.2 Divide Wall
Fig: Divide wall
5.2.3 Canal Head Regulator
Fig: Canal head regulator
5.2.4 Canal Portion

17. 12
The canal is lined with cement concrete.
Fig: Main canal
5.2.5 River training works
Chut blocks: It is provided to reduce the water pressure
Fig: Chut blocks
Stone pitching of banks: It is provided for the protection of banks from the flow of river water
Fig: Stone pitching at banks

18. 13
5.2.6 Impacts and achievements
Khageri Irrigation System was initially designed to irrigate 3,900 ha. However, the areas under irrigation
before IMTP intervention were only 2,400 ha in Khageri. The main reasons for lower irrigated areas in
these projects are:
-Reduction in the dependable water supply in the source due to the environmental degradation
-Lack of proper maintenance of canal
-Inequitable water distribution
-Poor on-farm water management practices
The available irrigation duty in Khageri is about 1.25 Vs per ha against the requirement of about 1.8
l/s/ha. It was therefore, decided to augment the supply in Khageri from Chitwan lift Irrigation system by
about 2.2 m3
/s. But it could not be done due to financial and technical reasons of the pumping systems.
Nevertheless, the irrigated areas upon management transfer have changed to 2,900 ha from existing 2,400
ha. The area under early paddy has increased from 350 to 600 ha. There is more equitable water
distribution in head, middle and tail portions of the system. Water distribution is being practiced in a
systematic way to make up the deficit in the canal system. However, the entire command area cannot be
fully irrigated unless the supply at the source is increased. With improved management, a total of 3,400
ha could be brought under irrigation. The changes observed so far in cropping intensity and efficiency are
given as below:
Table 2: Achievements in irrigation management
5.3 OBSERVATION ON NARAYANI LIFT IRRIGATION
Due to its fertile soils, Chitwan continued to be a major focus for irrigation development since 1960s. In
1972, Chitwan Irrigation Development Board (CIDB) was formed to direct the irrigation development in
the valley in recognition to its potential. Feasibility study begun on the same year. Under this board, an
executing agency, the Chitwan Irrigation Project (CIP) was set up to construct irrigation projects in the
district with the objectives of irrigating 10,400 ha of land thorough out the year and about 700 ha seasonally.
The CIP had three irrigation schemes namely; Narayani, Lothar and Khageri (MWR and CIDB, 1973).
The CIP initiated the NLIP in 1972, with the purpose of having year-round irrigation possibilities. The
project was completed in 1985 at the cost of NRs. 470,000,000 financed by the Asian Development Bank
(ADB). CIP was dissolved in 1994 and Narayani Lift Irrigation Office (NLIO) was established to look after
the O and M of the three irrigation systems previously operated under CIP.
In lift irrigation, lifting of water is done in two stages by two sets of Pumps i.e. pumping scheme “A” and
“B”. Pump house “A” is located in the bank of Narayani River and pump house “B” is located in
Chhatarpur, Narayangadh. There are five pumps in pumping scheme “A” (4+4+2+2+1=13m3
/sec) and four
pumps in Pumping scheme “B” (1.6+0.8+0.8+0.8=4m3
/ sec). But now only 4 m3
/sec water is available
S. N Details From To
1. Area under summer rice(ha) 2400 2900
2. Area under early paddy(ha) 350 600
3. Overall l efficiency (%) 30 36
4. Yield loss (%) 25 0
5. Irrigation turns(days) 11 11
6. Water share (l/s/ha) 3 1.25

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during transplanting of rice which is much lower than the requirements. Respondents reported that at least
6m3
/sec water is needed for them in the command areas of “B” canal.
In the first stage, pumping scheme “A” lifts water at the rate of 11m3
/sec to the height of about 22m onto
a link canal (500m). About 70 percent of lifted water is diverted to B canal at a rate of 7.8 m3
/sec. In the
second stage, remaining 30 percent of water from this link canal is lifted to the height of about 20m and
discharged at the rate of 3.2 m3
/sec to canal C by pumping scheme “B”. The system B supplements the
Khageri system with a capacity of 4.3 m3
/sec. About the cost effectiveness of NLIP, the project was
launched with the cost of 470,000,000 NRs. For O and M of NLIP during 40 years, it is estimated about
240,000,000 NRs. For electricity, it is estimated to be 500,000,000 NRs. So, the total cost of operation is
1210,000,000 NRs. But the income from water charge (levy) is found to be only 100, 000, 00 NRs. So,
there is the vital problem of how making the balance in the cost effectiveness of NLIP (Lohanee, 2010).
5.3.1 Pump
Fig : Pump
5.3.2 Inlet
Fig: Inlet of water to pumping system

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5.3.3 Outlet
Fig: Outlet to lifted water
This project has been proved a lot costlier clearly defined by the high-power consumption of about
Rs.10,800 per hour, repair and maintenance cost of 60,00,000-70,00,000 along with other charges of silt
repair and others. However, it is playing vital role in the rice production of the irrigated areas. Similarly, a
charge of RS.180 per bigha is being collected of which 40% goes to the government and 60% to the
committee from which earnings of about RS.10,50,000 is obtained. Thus, this project is also given a name
as “Seto hatti’’ as it has lesser earnings than the cost.

21. 16
5.4 OBSERVATION ON GANDAK BARRAGE
5.4.1 Divide Walls
Fig: Divide Walls
5.4.2 Main Canals
Eight numbers of gate were present in the Canal Outlet.
Fig: Main Canal

22. 17
5.4.3 Aqueduct
Aqueduct is constructed when bed level of the canal is sufficiently higher than the H.F.L. of the
drainage. It is the most commonly used cross drainage structure.
Fig: Aqueduct
5.4.4 Syphon Super passage
When the canal discharge is small in comparison to the drain and the canal bed level is lower than
the F.S.L. of canal, syphon is preferred structure to be adopted. In this case canal is syphoned
below drain.
Figure: Syphon Super passage

23. 18
5.4.5 Silt ejector canal
A trap like structure is used to trap the silt in the main canal and is ejected by flushing towards the
Silt ejector canal.
Fig: Silt ejector canal
5.4.6 Head Regulator
Head regulator is used to maintain the certain level of head in the canal before the flow occurs.
Below figure is of Distributary Head Regulator.
Fig: Distributary Head Regulator

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5.4.7 Distributary Channel
Distributary channel takes the water to the small portion of field from the main canal.
Fig: Distributary Channel
6. CONCLUSION AND DISCUSSION
In this way, our field visit was successfully completed with the proper achievement of all our objectives
that we were destined to accomplish. Hence the field visit was fruitfully terminated.
Nepal is landlocked agricultural country. Almost 80% of Nepalese depends upon agriculture. We had
concluded that such multi proposed irrigation projects should run effectively under systematic management
and maintenance for rising state of local people as well as to strengthen national economy. Local people as
well as Nepal government should monitor time to time these projects for efficient operation of irrigation
projects. The irrigation project plays an important role in the country's economy. The irrigation project is
directly and indirectly affecting the economy of the country and countrymen. Hence, proper operation of
every components of the system is vital and a small hurdle in the working can be proved a much
disadvantageous. Thus, proper care should be taken for proper functioning of the system. However, during
our field visit, we observed different problems like deposition of sediments in canal, stopping of working
of certain canal, silting and so on.
Thus, these problems need to be taken care of for which the related committee should be attentive and
active. All in all, the field visit is accomplished successfully from which we visualized the things we studied
in classroom.

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7. RECOMMENDATION
The problems of sedimentation and silting should be taken care of. Similarly, the concerned authorities
should regularly monitor and maintain the working condition of the irrigation projects so as to ensure
continuous supplies to people. In other ways, the government should be able to attract foreign companies
to invest and to further expand the irrigation project and hence extend its approachability in terms of its
command area.
Similarly, I would like to recommend the related personnel to regularly check and balance the problems
of the project and the same that might occur in future in case if they are not properly maintained at present.
Also, some of the components of the projects are very worse in condition and most of them are rusted.
Hence, a due concern should be given by all.
8. REFERENCES
1. Singh, G. (2010). Irrigation Engineering. New Delhi: Rajsons Publications
2. Garg, S.K. (2011). Irrigation Engineering and Hydraulic Structures. New Delhi: Khanna
Publishers
3. https://agris.fao.org/agris-search/search.do?recordID=NP19800525511
4. https://en.wikipedia.org/wiki/Gandaki_River
5. https://potlightnepal.com/2019/05/26/narayani-gandak-agreement-benefit-or-burden