Performance evaluation of the lien son irrigation system north vietnam

Need for study According to survey and assessment of the Ministry of Vietnamese Agriculture and Rural Development Diem, 2000, many of the irrigation systems are performing with low effi

PERFORMANCE EVALUATION OF THE LIEN SON IRRIGATION SYSTEM,

NORTH VIETNAM

by

Nguyen Van Tinh

A thesis submitted in partial fulfilment of the requirements for the

degree of Master of Engineering

Examination Committee: Prof A Das Gupta (Chairman)

Dr Mukand S Babel (Co-chairman)

Dr Roberto Clemente

Dr Mohammed Mainuddin

Nationality: Vietnamese

Previous Degree: Bachelor of Engineering

Hanoi Water Resources University, Vietnam

Scholarship Donor: Ministry of Agriculture and Rural

ABSTRACT

Irrigation performance indicators, which comprise engineering and economic indicators, allow an assessment on performance of irrigation systems Indicators can be use to compare the system to other systems Within the system, they can compared from year to year to indicate relative performance or trend

Dozens of irrigation performance indicators have been proposed over the years But they still receive relatively little use, and that use is mostly by researchers rather than managers According to Nelson (2002), each irrigation community needs to select a group of key indicators, that are applied often enough to establish and appropriate range

of values interpretation

IWMI provided a guideline with a set of 25 indicators, which consist of 4 groups: service delivery performance, productivity efficiency, financial and environmental performance This guideline is base to determine performance indicators for irrigation and drainage systems in the world

The Lien Son irrigation system located within the Red River Delta of Vietnam is chosen

as study area Based on available data of the study area, performance indicators will be determined, analysed and compared Then some recommendations can be provided to improve irrigation performance for the study area

ACKNOWLEDGEMENT

I would like to express my extreme gratitude to Prof A Das Gupta, my advisor and Dr Mukand S Babel, my Co-advisor, for their guidance and invaluable suggestion throughout my work Gratitude is also extended to the committee members, Dr Roberto Clemente for his comments and suggestion during the completion of this work

Deep appreciation is also to the MARD/DANIDA in Vietnam for providing me with the scholarship to study at AIT I also wish to express my appreciation to leaders, managers, lecturers of Hanoi Water Resources University for supporting me throughout my study at AIT Sincere thanks present to AIT for providing facilities throughout my study

I also would like to thank to all members of the Vinh Phuc Agriculture Department and the Lien Son Irrigation Management Company, who helped me enthusiastically during

my data collection

To entire WEM faculty and staff, thank you very much for your support To all classmate

in WEM, thank you for your friendship To all friends in Vietnamese Student Association, thanks for everything

Finally, I want to express my especial thank to my family, especially to my beloved parents, my lovely wife and son for their love, moral support during my study

TABLE OF CONTENT

Abstract i

Acknowledgement ii

Table of contents iii

List of tables iv

List of figures v

List of Abbreviation and Symbols vi

CHAPTER I INTRODUCTION 0T 1.1 Problem identification 1

0T 1.2 Need for study 0T1 0T 1.3 Objectives and scope of study 0T2 CHAPTER II DESCRIPTION OF STUDY AREA 0T 2.1 Location and area .0T3 0T 2.2 Climate and hydrology 0T3 0T 2.3 Topography and soil 0T5 0T 2.4 Land use .0T5 0T 2.5 Crop cultivation .0T5 0T 2.6 Irrigation system and facilities 0T6 2.7 Present operation and management 7

CHAPTER III LITERATURE REVIEW 9

CHAPTER IV MEDOTHOLOGY 14

0T 4.1 Benchmarking in the Irrigation and Drainage sector .0T10T4 0T 4 2 Data collection and analysis .0T10T4 0T 4.2 1 Data collection .0T10T4 0T 4.2.2 Data processing .0T10T6 CHAPTER V ANALYSIS, RESULTS AND DISCUSSION 21

0T

5.1 Service delivery performance indicators 0T21

0T

5.1.1 Reference evapotranspiration .0T21

0T

5.1.2 Irrigated area under different crops 0T20T2

0T

5.1.3 Irrigation requirement .0T20T4

0T

5.1.4 Water supply .0T20T6

0T

5.1.5 Over all efficiency 0T20T7

0T

5.1.6 Annual irrigation water delivery per unit irrigated area……… 0T20T7

0T

5.2 Productive efficiency indicators 0T20T8

0T

5.2.1 Gross annual agricultural production 0T20T8

0T

5.2.2 Total annual agricultural production 0T30T0

0T

5.3 Finalcial performance indicators 0T30T2

5.3.1 Total number of personnel 0T30T2

0T

5.3.2 Irrigated area per person unit .0T30T2

0T

5.3.3 Total costs 0T30T3

0T

5.3.4 Maintenance Budget Ratio 0T30T6

0T

5.3.5 Personnel Cost Ratio 0T30T7

0T

5.3.6 Cost of irrigated area unit 0T30T7

0T

5.3.7 Total water fee collection 38

0T 5.3.8 Water fee collected per irrigated area unit 0T40T0 0T 5.3.9 Ratio of water fee collection per 0T 40T0 CHAPTER VI CONCLUSIONS AND RECOMMENDATIONS 42

6.1 Conclusions 42

6.2 Recommendations 42

REFERENCES 44

Appendix I Climate Data 46

Appendix II Crop Data 49

Appendix III Cropwat output 55

Appendix IV Currency exchange rate 78

LIST OS TABLES

Table Title Page

Table 2.1.: Area distribution on elevation 5

Table 2.2 Number of cooperatives 7

Table 2.3 Percentage of Production yield as water fee 7

Table 2.4 Total budget received by LIMC from Vinh Phuc PPC 8

Table 4.1: Data and information for evaluating indicators 14

Table 4-2: Data processing 16

Table 5.1: Average monthly value of climatic parameters 22

Table 5.2.: Total rainfall 23

Table 5.3: Reference Evapotranspiration 24

Table 5-4: Irrigated area under different crops 24

Table 5-5 : Effective Rainfall 25

Table 5-6: Irrigation water requirement 26

Table 5-7: Water volume derived to the system through Lien Son diversion and Bach Hac pumping station 27

Table 5.8: Over all efficiency (OAE) 28

Table 5.9: Annual irrigation water delivery per unit irrigated area 29

Table 5.10: Total crop Area, Productivity and Yield 30

Table 5.11: Total annual agriculture production 32

Table 5.12: Number of personnel 33

Table 5.13: Irrigated area per person unit 33

Table 5.14: Total costs 35

Table: 5.15: The Maintenance Budget Ratio 37

Table 5.16.: The Personnel Cost Ratio 38

Table 5.17: Ratio of total cost per irrigated area 39

Table 5.18: Water fee collection 40

Table 5.19 : Water fee collected per irrigated area unit 41

Table 5.20.: Ratio of water fee collection per total cost 41

LIST OF FIGURES

Figure Title Page

Figure 2.1 Map of the study area 4 Figure 5.2: Crop calendar 25

LIST OF ABBREVIATION AND SYMBOLS

ACIAR = Australian Centre for International Agricultural

Research

Drainage

for Technology and Research in Irrigation and Drainage

CHAPTER I INTRODUCTION

1.1 Problem identification

With increasing population and demand for food, sustainable production increase from irrigated agriculture must be achieved With limited freshwater and land resources, and increasing competition for these resources, irrigated agriculture worldwide must improve its utilization of these resources Few would disagree with these statements, yet we do not have a way of determining the present state of affairs with respect to irrigated agriculture The question—how is irrigated agriculture performing with limited water and land resources?—has not been satisfactorily answered This is because we have not been able

to compare irrigated land and water use to learn how irrigation systems are performing

relative to each other and what the appropriate targets for achievement are

With about 80 millions inhabitants and 331,700 square kilometers total area, of which one third only is covered by plains, the irrigated agriculture in Vietnam has become one

of the major sectors in the national economy and food security strategy Irrigation water management thus has enormous economics implications for this country While the structural infrastructure for irrigation- comprising of reservoirs, canal networks, drainage works and delivery systems-is created at a huge financial investment, a commensurate effort is also essential on developing scientific water management policies Development

in systems science, operation research and mathematical modeling for decision making under uncertainty have been usefully exploited for water resources management in many technologically advanced countries Applications of such mathematical techniques in irrigation water management in developing country – at both macro as well as micro level – will lead to significant economic benefits

In most of the irrigation system in the North of Vietnam, water is increasingly becoming

a scare resources due to the pressure from increasing water requirement In addition, due

to change climate, the serious deforestation in the watershed, etc, water resources, especially in the dry season, is much more reduced comparing to the time when the system was designed

In view of the foregoing discussion, an effective method in management of natural resources for irrigated agriculture on the sustainable basis is essential since the efficiencies of both water and land use are low, and fewer opportunities are there to increase irrigated areas by the development of new system

By considering all the different criteria, a better management of the utilization of water resources is required to promote the water use efficiency

In this study, the Lien Son Irrigation and Drainage System is chosen as study area

1.2 Need for study

According to survey and assessment of the Ministry of Vietnamese Agriculture and Rural Development (Diem, 2000), many of the irrigation systems are performing with low efficiency, the operation cost is high, especially for pumped irrigation of the Red River Delta in the North area of Vietnam The major reasons causing low efficiency of

irrigation systems are: a) many of them had been operated for years, but insufficiently rehabilitated; b) investment for irrigation systems had not been properly planned; and c) policies of institutional management had some problems, especially regulations of water fee collection In addition, in the irrigation systems of the Red River Delta, low efficiencies for water delivery and water use are major impediments to increasing crop productivity (ACIAR, 1999)

The Lien Son Irrigation and Drainage System belongs to the Red River Delta of Vietnam The total area is 44439 ha It has been built since 1914 with water resources from Pho Day river at the Lien Son diversion The system started operation in 1917 with initial irrigation area of 17,000 ha In 1962,the Bach Hac pumping station with capacity

of 11.2 m3/s was constructed, it take water from Red River for supplying water to system , and the irrigated area of system was expanded up to 23,000 ha

In recent years, many rehabilitation projects for the Lien Son irrigation canal system have been implemented for improving delivery efficiency, reducing water percolation However, the question is what is reasons of low irrigation performance and how to improve it?

For those reason, the study is essential to find out the appropriate management strategy which will overcome the existing problems of the Lien Son irrigation system

1.3 Objectives and scope of study

The main objective of study is to analyze and evaluate irrigation performances of Lien Son system and based on these results provide recommendations for improving irrigation system management

The Benchmarking Performance procedure recommended by IWMI is issued for analysis and evaluation of irrigation performance of Lienson Irrigation System with the scope of work as following:

a) Collection data: Including data of hydrometeorology, crops, irrigation management costs, water fee,

b) Estimating of data: Calculate crop water requirement, irrigation requirement,

c) Calculating indicators: Including 3 groups of indicators as service delivery performance, productive efficiency and financial performance

d) Discuss of results: Based on results of indicators calculated, to discuss and give comment for them

e) Recommendations : Based on above results for provide some recommendations on to improve irrigation performance for the study area

CHAPTER II DESCRIPTION OF STUDY AREA 2.1 Location and area

The Lienson Irrigation system is the midland plain at the left-bank of Red River It includes 5 districts Mong Cau, Tam Duong, Vinh Tuong, Yen Lac, Binh Xuyen and Vinh Yen town of Vinh Phuc Province It is within the longitude of 104o55’ to 106o12’ East and the latitude of 21o12’ to 21o48’ North The system has boundaries with Tam Dao mountain at the North and North-East, Hanoi city at the South-East, Red river at the South and South-West The location of study area along with its layout is shown in Figure 2-1

This system covers an area of 44439 ha in which 23.000ha cultivated area with irrigation

It plays the substantial role of agriculture in the economic development of the Vinh Phuc province The total population living in this area is 748,568 inhabitants.(Vinh Phuc statistical Department, 2002)

2.2 Climate and hydrology

The climate of the study area belongs to the tropical monsoon zone, consisting of the dry season, November to March and the rainy season, April to October As the records in

20 years (1983-2002) duration at the Vinh Yen meteorological station, the mean annual rainfall is 1662 mm, of which 84.5% fall in the rainy season, specially in July to September In dry season, the mean monthly rainfalls are recorded at 16-45 mm The average sunshine is short 4.2 hours per day, and specially short in dry season as 2.4 hours per day The annual mean temperature is 23.7 oC, the hottest month is July in terms of monthly mean temperature(28.7oC), and the lowest is in January (16.2 oC) The annual relative humidity is high, as 84.5%

The prevalent wind direction in winter season is North-East with average speed of about 2.0 m/s The prevalent wind direction in summer season is South-East with average speed

of about 1.8 m/s Typhoons and storms occurs in the rainy season from July to October There are about 5.5 typhoons landed in a years

The Red river basin (A=169,000 km2) is a wider river system, which is the second in Vietnam in terms of catchment area, annual mean discharge of about 3,715 m3/s (average 1960-2002), and the lowest discharge of 500 m3/s (April, 1960) at the Son Tay observation station, about 10 km downstream of the study area

The Pho Day river basin (A=1,387 km2) is a small river, originated in Long Hoa Mountain of Tuyen Quang province at the North of study area According to statistical data (1960-2002), discharge of the Pho Day river at the Lien Son station as following:

- In dry season: Max discharge of 11 m3/s to 13 m3/s in April and min of 4.5 m3/s to 6.0 m3/s in March

- In rainy season: Max discharge of 60 m3/s to 83 m3/s in June and min of 12 m3/s to 15 m3/s in September

Figure 2-1: Map of study area

2.3 Topography and soil

The direction of the surface slope is from North-West down to South-East and from West to East The ground surface elevation varies from +5 to + 16.5 m above the MSL, in which 57.49% of area is from +8 to +11 m above the MSL The cultivated land, build up

by alluvial soil of Red river, is light loamy sand The low land near by the rivers are glay

or medium loam The high land near by the mountain or hill are feralitic Area distribution on elevation are shown in table 2.1

Table 2.1.: Area distribution on elevation

The study area with 6 districts which have 23,000 ha of agricultural land of which 20,400

ha has devoted to rice cultivation, 2,600 ha was dedicated for upland crops (maize, soybean, vegetables) Winter crops as vegetables occupies small area of 1,250 ha, accounting for 5.4% total agricultural area About 1,600 ha produces only one crop of dry season because it is subjected to deep flooding during the rainy season

The present cultivation area per farmer is 360 -540 m2 which consist of 1-3 plots

(Source: Vinh Phuc statistical Department)

According to statistical data (Vinh Phuc statistical Department, 2002), average rice yield

of study area(4.67 tons/ha) exceeded the yield capacity of national level (4.4 tons/ha) in which Vinh Tuong district occupied the highest yield (5.50 tons/ha) and Mong Cau is the

provinces in the Red river Delta, such as Ha Tay and Thai Binh provinces has raised rice yields to more than 5 tons/ha/crop

U

Maize

It has two crop seasons a year: spring maize and summer-autumn maize The average maize yield of this area in 2002 of 3.35 tons/ha is higher than the national average of 2.9 tons/ha, in which Vinh Tuong district occupied the highest yield (3.9 tons/ha) and Vinh Yen is the lowest (3.0 tons/ha)

U

Soybean

It has two crop seasons a year: spring and summer-autumn soybean as maize too Yen Lac district occupied the highest yield (1.38 tons/ha) and Mong Cau is the lowest (1.8 tons/ha)

2.6 Irrigation system and facilities

The irrigation in the study area is supplied by two head works of Lien Son diversion and Bach Hac pumping station, in which Bach Hac has main responsibility to supply in dry season while Lien Son is in wet season

1 The Lien Son diversion: It was built in 1914 on the Pho Day river Its long is 105m, comprises 3 spans, height of 5.16m, the elevation of spillway is 21.13m Its design irrigation area is 17,000 ha cultivated area

Main intake sluice: located at head of main canal of 15m upstream of diversion dam including 5 units with dimension of 1.3x2.3 m, elevation of bottom on upstream is +14m and downstream +13m, design discharge is 17 m3/s

2 Bach Hac pumping station:

It was built up in 1962, take water from Red river Capacity of pumping was designed of 11.2 m3/s with 6 units in which of 2.225 m3/s /unit Head of design is 9m As survey in

2001, it was still in good performance

3 The canal system:

At the present, the canal system of the study area is in good condition because almost of canal from main canal to on-farm canal has been lined by concrete or brick from 1995 to present In this area, 86km of main canal, 263 in-take structure and 13 secondary canal,

294 over level sluices and many other structure such as siphons, divert sluices, checks, drops, transitions,

Main canal: At the end of 2002, 74 km lined by concrete of total 86 km The width of bottom changes from 2.5 m at the end to 11.5 m at the head of canal The average bed slope is 2*10-4

Secondary canal: 13 ones with length of 3-9.5 km, the width of bottom is from 3 to 10m, irrigation service area of each canal is about 200-1500 ha, about 70% lined (counted at the end of the year 2002)

On-farm canal network: Set up completely to reach to all farm, estimated about 60% this level canals lined by brick at the same time in 2002

Local scale pumping station: Water on the irrigation canals flow down to drainage canal system due to underdeveloped on-farm ditches, insufficient and inoperative check structures, and poor management Therefore, it is necessary to pump up again to the field

It has total 11 local pumping stations with capacity of 1000 to 2500 m3/hr, managed by communes or cooperatives In addition, 4 drainage pumping stations within the study area are responsible to drainage by flooding in rainy season

2.7 Present operation and management

The irrigation system in the study area is operated and managed by the Lien Son irrigation management company(LIMC) as state company of the Vinh Phuc province Central office of company is located in Vinh Yen town The functions of the company are under the supervision of a director and two deputy Under them are 4 departments for finance, administration, planning and technical activities

The central office is responsible to administrate main activities of company consisting of operation, maintenance the main canal system and two head works of Lien Son diversion and Bach Hac pumping station

The LIMC is assisted by 6 sub-companies, one per concerned district, those are Mong Cau, Tam Duong, Vinh Yen, Vinh Tuong, Yen Lac and Binh Xuyen The sub-company

is responsible for irrigation, drainage in each area of district Each sub-company has a set

of irrigation group, each being responsible for about 1000 ha The irrigation group works with cooperatives to manage water, maintain facilities and collect water fee The company have to pay expenses for cooperatives to collect water fee The number of cooperatives of each district is given in Table 2.2

Table 2.2 Number of cooperatives

District Mong

Cau

Tam Duong

Vinh Tuong

Yen Lac Binh

Xuyen

Vinh Yen

Table 2.3 Percentage of Production yield as water fee

1 - Irrigated by gravity from Lien

Son diversion

2 - Irrigated by pumping stations 5-7.5% 4-6.5%

Water fees are reduced by half for farmers who get water from the irrigation system but

is supplied directly by gravity into farmer fields of about 60% irrigated area and about 40% of the irrigated area of farmers need a manual lift with a scoop handled or portable pumping to get for water to the farm

The water fee varies from one cooperative to another, this fee of each cooperative obey the regulation of PPC and plus extra fee (if any) for electric fee of cooperative pumping station, field application costs

Every six months farmers have to pay an individual water fee which is collected by cooperatives The water fee is expressed in kilo of paddy but farmers can pay in cash or

in kind Standard of water fee amount ranges from 380 kg/ha/year in Tam Duong district

to 644 kg/ha/year in Vinh Yen district

The central office manages the financial and personnel affairs of company All costs (salary, maintenance, operation, ) and revenues(water fee, ) of sub-companies must be reported and approved by Board of Director The general costs of company such as tax, insurance, are paid by central office

The Government still maintains the policy of subsidizing total cost of drainage works for Irrigation Management Company such as electric fee of drainage pumping station, maintenance costs of drainage canals, structures, Every year, PPC approve total budget

of these costs for the Irrigation Management Company based on report submitted Table 2.4 shows total budget which LIMC has received from Vinh Phuc PPC during 5 years (1998-2002)

Table 2.4 Total budget received by LIMC from Vinh Phuc PPC

* Source: Lien Son Irrigation Management Company

- Currency exchange rate: Appendix 4

CHAPTER III LITERATURE REVIEW

Nelson et al (2002) provided a set of performance indicators for irrigation canal system

managers or water user associations which can be applied within limited time, money, and information resources available to the typical manager or water user associations Indicators are oriented toward items that directly or indirectly affect water deliveries, rather than indicators like crop yields that are also affected by other factors Indicators also oriented toward the existing system, aspects which do not require major modification

of the infrastructure

Peter et al (2002) summaries the background to irrigation water provider benchmarking

in Australia, summaries why the irrigation providers participate in the annual benchmarking report, outlines what has been achieved by providing the benchmarking reports and explores the challenges for benchmarking in the future

Molden et al (2001) provided a set of comparative performance indicators, which relates

outputs from irrigated agriculture to the major inputs of water, land, and finance Nine indicators are presented with the objective of providing a means of comparing performance across irrigation systems These indicators require a limited amount of data that are generally available and readily analyzed Results of application of the indicators

at 18 irrigation systems are presented and large differences in performance among systems are shown In spite of uncertainties in estimation of indicators, the large differences discerned by the indicators justify the approach taken

IPTRID Secretariat, FAO(2000) provided Guidelines for Benchmarking Performance

in the Irrigation and Drainage sector support procedures to assist in the process of data

identification, collection, entry, processing and analysis for the irrigation and drainage benchmarking exercise

Sakthivadive et al (1999) introduced comparative performance indicators that make it

possible to see how well irrigated agriculture is performing at the system, basin or

national scale As a tool for measuring the relative performance of irrigation systems or tracking the performance of individual systems the IWMI comparative performance

indicators help:

• Policy makers and planners to evaluate how productively land and water resources are being used for agriculture, and to make more informed strategic decisions regarding irrigation and food production

• Irrigation managers to identify long-term trends in performance, to set reasonable overall objectives and to measure progress

• Researchers to compare irrigation systems and identify factors that lead to better performance

Kloezen and Garcés-Restrepo (1998) In addition to using process indicators, the

International Water Management Institute (IWMI) suggests using a minimum set of comparative indicators to assess hydrological, agronomic, economic, financial, and

environmental performances of irrigation systems The aim of applying comparative indicators is to evaluate outputs and impacts of irrigation management practices, interventions across different systems and system levels, as well as to compare various irrigation seasons and technologies with one another The application of comparative indicators should provide system managers, researchers, and policy makers with information on differences in performance and, as a consequence, enable them to identify gaps in irrigation management policies Generally, process indicators are used to assess actual irrigation performance relative to system-specific management goals and operational targets It is believed that, in comparison with process indicators, the application of comparative indicators requires data collection procedures that are less time- and resource-consuming

To test their applicability and usefulness, comparative indicators were applied to the Alto Rio Lerma Irrigation District (ARLID) in Mexico that has a gross command area of 113,000 hectares, as well as to two modules within the district The results and data collection procedures of the comparative indicators were compared with those of a small set of process indicators

Bos et al (1994) introduced a framework irrigation managers can use in assesing

performance of irrigation and recommends a specific set of indicators for measuring performance that the authors believe are practical, useful, and generally applicable Although the primary focus is on the management of canal systems for agricultural production, the paper also discusses indicators that can be used for assessing longer term performance, including physical, economic and social sustainability Finally, the paper highlights the crucial importance of strategic, as well as operational management performance, and the necessity of having an incentive system that encourages managers

to improve performance

Bos (1997) summaried the performance indicators currently used in the Research

Program on Irrigation Performance Within program field data are measured and collected to quantify and test about multidisciplinary performance indicators These indicators cover water delivery, water use efficiency, maintenance, sustainability of irrigation, environmental aspects, socio-economics and management The indicators now are sufficiently mature to be recommended for use in irrigation and drainage performance assessment

Small (1996) gave an overview of Irrigation operation and maintenance in Vietnam

under economic restructuring Institutional and financial considerations Vietnam's policies to establish a market economy are reshaping the state organizations and agricultural cooperatives that have operated and maintained irrigation systems The new policies emphasize financial autonomy for state enterprises, and a shift in the responsibilities of the agricultural cooperatives away from collective production activities Specific policies and institutional arrangements vary considerably among the provinces In Quang Nam-Da Nang province in central Vietnam, the agricultural cooperatives generally still play an important role in irrigation O&M at the tertiary and quaternary level, serving as intermediaries between individual households and the state enterprise that operates the headworks and the primary and secondary canal network of government irrigation schemes The cooperatives also have full responsibility for many small pump irrigation schemes The state irrigation enterprises have partial financial

autonomy, financing their activities primarily from irrigation fees collected from the farmers The power to set the fees, however, resides with the provincial government and not with the irrigation enterprises The fee, which is an area-based fee differentiated by crop and season, is set in terms of paddy to facilitate maintaining its real value in the face of inflation Both cost and equity factors are taken into consideration in setting the schedule of fees The fees in government gravity irrigation schemes are fairly high by comparison with other Asian countries; however they are lower than typically paid by farmers in the small pump irrigation schemes operated by the agricultural cooperatives

Lank Ford & John Gowing (1995) provided a method is presented to analyse the impact

of the selection of irrigation gates on operational performance of the Sungai Muda Irrigation Scheme in Malaysia The method examines the discharge capacity of the water control gates at all levels in order to compare the specific water supply (the ratio of supply to command area) with the specific water demand which is the required hydromodule The term hydromodule is the reciprocal of "waterduty" and thus has units

of litres/second/hectare The greater the deviation between the two, the greater the potential loss of control during the operation of the scheme The method is relatively simple but is more complex in this particular example as two hydromodules are used for the irrigation of basin rice; one for the presaturation period and one for the normal supply period The most common cause of loss of water control is found to be provision of oversized turnout gates at the head of secondary and tertiary canals Such design approximations enable more water to be used in those command areas thus leading to waste and to shortage of water in other areas It is suggested that during design and rehabilitation of irrigation schemes, the operational implications of design approximations should be examined more carefully

Makomb et al (1998) analysed the water management performance of small holder

irrigation systems in Zimbabwe The government and fanner managed systems are compared in terms of their ability to match desired with actual water supply Desired supply is defined as crop water requirements adjusted downwards by rainfall where relevant The Theil measure of accuracy of forecasts is used to calculate the error committed by each system in trying to match water supply and demand The analysis shows that, everything else being equal, the farmer managed system performs better than the government system in matching supply and demand This means that the farmer managed systems should be encouraged for future small holder irrigation development in Zimbabwe

Small & Rimal (1995) Based on a simulation model reflecting physical and economic

conditions typically found in rice irrigation systems in Asia, the irrigation performance implications of alternative water distribution rules for dry season irrigation are evaluated under varying degrees of water shortage The rules examined reflect differing water distribution strategies designed either to maximize conveyance efficiency, economic efficiency, or equity; or to achieve a balance between efficiency and equity objectives Irrigation performance is evaluated using several efficiency measures reflecting the physical, agronon-dc and economic productivity of water, and one measure of equity Economic efficiency and equity among farmers within the portion of the irrigation system that is "on" in any given season are shown to be complementary, and not competing objectives Economic efficiency and equity among all farmers within the command area

of the irrigation system are largely complementary strategies at the lower levels of water shortage, but with increasing shortage, significant tradeoffs develop between these objectives An operational rule for water distribution under a goal of maximizing economic efficiency is developed, and the data requirements for its implementation are shown to be modest Under the model's assumed conditions of dry season rice production dependent solely on surface irrigation for water, the distribution strategy designed to maximize conveyance efficiency results in only modestly lower levels of economic efficiency and equity than could be achieved by the strategy designed to maximize economic efficiency

Zalidis et al., (1997) provided a method for estimating of a network irrigation efficiency

to cope with reduced water supply The overall irrigation efficiency, ep, for the irrigation networks in the Thessaloniki plain, in Northern Greece, was estimated from historical data, spanning eight years Irrigation networks differ regarding the method of water delivery and the method of field application

Overall irrigation efficiency is the parameter which helps to adjust water supply to meet the actual crop water requirements A method is introduced which calculates networks ep using spatially distributed data Efficiency values for all systems were calculated using the proposed method Seasonally averaged ep values for eight years for 32 (surface and sprinkler) irrigation networks ranged from 0.38 to 0.8 1 Analysis ofthe time series ep values can identify operational factors that might affect network ep Sprinkler and surface network irrigation efficiencies did not show any significant difference

Thoreson et al (1997) provided a framework for determining the effect of maintenance

events on irrigation system flows is described Standard definitions for corrective and preventive maintenance are presented and two maintenance objectives and six classifications are established Maintenance activities and decision criteria common to many irrigation systems are suggested A format for describing these and other maintenance activities is proposed A methodology for setting decision levels for maintenance activities is presented Maintenance cost is compared with income lost as a result of less than maximum production because water supplied was insufficient for crop requirements This comparison demonstrates that maintenance decision levels should be set so that maximum evapotranspiration can be achieved Budget request forms and report forms are presented with examples of actual maintenance events showing the expected and actual impact on system flows

Cross (1999) developed a general introduction into the concepts of a flexible irrigation

water supply in rate, frequency and duration together with the benefits to the farmer for doing so A flexible water supply allows the farmer the opportunity to choose an on-farm irrigation practice that best meets the needs of the desired crop, the cost and availability

of labor, and other local economic or social situations As water quality issues are more closely tied to the issues of water quantity, water use efficiency must improve A flexible irrigation water supply can lead to improved efficiencies Non-point-source pollution and in-stream flows also become factors in other social issues such as the care of threatened and endangered species Flexible supplies can again help This paper also shows, through

a case study, the application of a limited rate arranged system to an irrigation district in Washington State where significant flexibility has led to efficient water use and economic and environmental benefits

FAO (1990) provided Guideline for computing crop water requirement

This publication presents an updated procedure for calculating reference and crop evapotranspiration from meteorological data and crop coefficients The guidelines are intended to provide guidance to project managers, consultants, irrigation engineers, hydrologists, agronomists, meteorologists and students for the calculation of reference and crop evapotranspiration They can be used for computing crop water requirements for both irrigated and rained agriculture, and for computing water consumption by

agricultural and natural vegetation

Agricultural College of Velp, Netherlands (1992) provided Cropwat 7.0: User guide

CROPWAT version 5.7, issued in 1992, is written in BASIC and runs in the DOS environment (FAO of the UN, 1992) The English version of CROPWAT 5.7 is replaced

by CROPWAT version 7.0, which contains a completely new version in Pascal, developed with the assistance of the It overcomes many of the shortcomings of the original 5.7 version

The program uses the same Penman Monteith methodology as used in CROPWAT versions 5.7 and uses the same data such as the CLIMWAT climate and rainfall files The program uses a flexible menu system and file handling, and extensive use of graphics Graphs of the input data (climate, cropping pattern) and results (crop water requirements, soil moisture deficit) can be drawn and printed with ease Complex cropping patterns can be designed with several crops with staggered planting dates

CropWat 7.0 uses the same equations as in CROPWAT 5.7, but there are some differences between the menu systems and the types of calculation permitted

CHAPTER IV METHODOLOGY

4.1 Benchmarking in the Irrigation and Drainage sector

Benchmarking has only recently been introduced into irrigation and drainage sector The

first Benchmarking report for 1997/98 reported by the Australia National Committee of

Irrigation and Drainage (ANCID) on 33 irrigation systems and used 15 performance

indicators and the 1998/99 Benchmarking report reported on 46 systems and used 47

performance indicators

An international initiative on Benchmarking in the irrigation and drainage sector began in

1999 Initially coordinated by IPTRID, this is joint initiative of the WB, IPTRID, IWMI,

ICID and FAO The initiative was launched at a workshop held in Rome, August 2000 in

which the principles and objectives of benchmarking were discussed As results, a set of

guidelines for benchmarking were prepared and widely disseminated (Malano & Burton,

2001), a dedicated website to disseminate benchmarking information was established

by IWMI (IWMI, 2001) This guideline provides a set of 27 indicators, which consist of 4

groups: service delivery performance, productivity efficiency, financial and

environmental performance

Based on guideline and particular characteristics of the study area , this chapter deals

with the details of data collection, data processing and comparative analysis

4 2 Data collection and analysis

4.2 1 Data collection

There are 3 groups of indicators for evaluating service delivery performance, productive

efficiency and financial performance Data need for evaluating each indicator, frequency

of observation and the sources for data collection are provided in table 4.1

Table 4.1: Data and information for evaluating indicators

- average percolation rate

- crop coefficient

- area planted to each crop

Monthly Vinhyen

meteorologicalstation and

At least twice/day

Lienson Irrigation management company LIMC

Secondary

3 Total annual volume

of total water supply

-Inflow at Lienson diversion and Bachhac pumping station

- daily rainfall at Vinhyen meteorological station -discharge pumping from groundwater

4 Total annual irrigated

crop area

- Irrigated crop area for each individual crop of 2 season:wet, and dry

annual LIMC and

Agricultural Departments (AD)

2 Irrigated area per

person unit

**

3

Total MOM* cost

- Bulk water fee

- staff cost

- operation cost (electricity for operation pumping station and equipment,…)

- maintenance cost (canal, facilities,…)

- Overheads(include administrative expenses, insurances, taxes, )

4 Maintenance Budget

Ratio

**

6 Ratio of cost and

irrigated area

**

7 Gross water fee

LIMC and

AD

Secondary

8 Water fee per

irrigated area unit

**

9 Ratio of water fee

gross per cost

Data collected have to be processed before calculating indicators Procedures of

processing of each set of data collected (refer Table 4.1) are provided in Table 4.2

Table 4-2: Data processing

1 - Monthly (rainfall, air

temperature, air humidity, wind speed, sunshine hour,…)

• average percolation rate

• crop coefficient Kc

• area planted to each crop

VETRNetR= ∑(EtcRi R - RReR)ARiR

VETR Net R = Total volume of water consumed by crops less effective rainfall (mP

3

P

)

i = Crop type EtcR i R= Evapotranspiration from

crop i from planting to harvest

2 Irrigated crop area for each

individual crop of 2 seasons:wet, dry

whole system area in each season and whole year

ha

3 -Inflow at Lienson diversion and

Bachhac pumping station each

6 - Salary, bonus, cost for travel, of

personnel at districts and center

Aggregate up for whole company US$

8 Water fee collection of

sub-companies

Aggregate up for whole company US$

1 Crop water requirement

The main aim of an irrigation system is to supply irrigation water to fulfill crop water requirement Therefore the determination of crop water requirement is essential in assessment of irrigation performance, as it is needed both in efficiency and adequacy indicators

During its growth, crop requires water for digestion, photosynthesis, transport of mineral and photosynthesis, structural support, growth, and evapotranspiration Because other use needs very small percentage of water, they can be considered insignificant Crop water requirement can be approximated by evapotranspiration (ET)

Crop evapotranspiration could be determined by direct measurement or calculated from crop and climate data In this study, ETo is computed by using Penman-Monteith approach which is currently considered as best performing combination equation Reference evapotranspiration (ETo) is defined as the rate of evapotranspiration from a hypothetic crop with an assumed crop height of 12 cm, a fixed canopy resistance of 70 sm-1 and an albedo of 0.23, closely resembling the evapotranspiration from an extensive

surface of green grass of uniform height, actively growing, completely shading the

ground and not short of water (Smith, 1990)

The estimation of the ETo can be determined with the combination formula based on the Penman-Monteith approach When combining the derivations found for the aerodynamic and radiation terms as presented above, the combination formula can be noted as (Allen

et al., 1998):

)1.4 (

)(

2273

900)

(408

0

U

ed ea U T

G Rn ETo

++

∆

−+

where: ETo reference crop evapotranspiration [mm/day]

R, net radiation at crop surface [MJ/ mP

U2 wind speed measured at 2m height (m/s)

(ea-ed) vapour pressure deficit [kPa]

∆ slope vapour pressure curve [kPa/P

ETo reference crop evapotranspiration [mm/day]

3) Mid season stage

4) Late season stage

Kc value for difference crops under Red river delta conditions is not available so that in this study, Kc values is taken by FAO, Irrigation and Drainage Paper No.56 (Richard G Allen, 1998), the detail values are shown in Appendix 3

In this study, ETo and ET will be computed using CROPWAT (FAO of the LJN, 1992) CROPWAT is a decision support system developed by the Land and Water Development Division of FAO Its main functions we (i.) to calculate reference evapotranspiration, crop water requirements and crop irrigation requirements, (ii) to develop irrigation schedules under various management conditions and scheme water supply, and also (iii)

to evaluate rained production and drought effects and efficiency of irrigation practices The CROPWAT is meant as a practical tool to help agro-meteorologists, agronomists and irrigation engineers to carry out standard calculations for evapotranspiration and crop water use studies, and more specifically the design and management of irrigation schemes It allows the development of recommendations for improved irrigation practices, the planning of irrigation schedules under varying water supply conditions and the assessment of production under rained conditions or deficit irrigation

The calculations of crop water requirements and irrigation requirements were carried out with the inputs of climatic and crop data The development of irrigation schedules and evaluation of rained and irrigation practices were based on a daily soil-water balance using various options for water supply and irrigation management conditions Scheme water supply was calculated according to the cropping pattern provided

CROPWAT version 5.7, issued in 1992, is written in BASIC and runs in the DOS environment (FAO of the UN, 1992) The English version of CROPWAT 5.7 is replaced

by CROPWAT version 7.0, which contains a completely new version in Pascal, developed with the assistance of the Agricultural College of Velp, Netherlands It overcomes many of the shortcomings of the original 5.7 version CROPWAT for WINDOWS contains a CROPWAT version in Visual Basic to operate in the Windows environment It has been developed with the assistance of the International Irrigation and Development Institute (IIDS) of the University of Southampton, UK (Clarke, 1998)

In this analysis, CROPWAT 7.0 is employed because in one hand it is an improved version of CROPWAT 5.7 and on the other hand it is able to calculate crop water requirement for rice which is unable to calculate it, and CROPWAT for Windows is used

to calculate crop water requirement for upland crop To calculate the crop water requirement, data needed in CROPWAT (FAO of the UN, 1992 and Allen and others, 1998):

2 Humidity

The daily actual vapor pressure, ea, in kilopascals (kPa) is required The actual vapor pressure, where not available, can be derived from maximum and minimum relative humidity (%), psychometric data,(dry and wet bulb temperatures in OQ or dew-point temperature ('C)

4 Wind speed

The daily wind speed in meter per second (m/s) measured at 2 m above the ground level

is required It is important to verify the height at which wind speed is measured, as the wind speeds measured at different heights above the soil surface differ

2 Effective rainfall

Effective rainfall in relation to crop water requirement is the portion of total annual or seasonal rainfall that is useful directly or indirectly for crop production at the site where it falls Effective rainfall can be measured directly or determined by formula Among several formulae available, USDA SC method is the most appropriate to apply in this study to analyze effective rainfall Mathematically, the USDA SC method for monthly effective rainfall can be written as:

Pe = (125 - 0.2 * Pmon)* Pmon/ 125 for Pmon < 250 mm/month) (4-3)

Pe = 0.1 * Pmon + 125 for Pmon > 250 mm/month) (4-4)

in which

Pmon: monthly rainfall (mm)

3 Deep percolation and land preparation

Seepage and percolation are the lateral and vertical subsurface movement of water Texture and structure of the soil profile, elevation of water table, soil permeability, depth

of impervious layer, and topography generally determine these natural phenomena Paddy field, characterized by nearly level or very gently slopping soils with clay soils and with low water table level below the ground surface, is estimated to have a seepage and percolation of 6.096 mm/day (WASCOS, 1983)

The estimates assume that the soil of the paddy is wet tilled prior to transplanting The deep of water required for land preparation of paddy includes land soaking, through seepage and percolation and evaporation So that the water requirement for land preparation is taken as 200 mm (Ministry of Agriculture of Vietnam, 1986) For other crops, land preparation can be neglected

4 Irrigation requirement

The irrigation requirement of a crop is the total amount of water that must be supplied by irrigation to a disease-free crop growing in a large field with adequate soil water and fertility and achieving full production potential under the given growing environment (Doorenbos and Pruit, 1977) The irrigation requirement includes water used for crop consumptive use, maintaining favorable salt balance within the root zone and overcoming non-uniformity and inefficiency of irrigation, The irrigation requirement excludes water from natural sources such as precipitation that crops can effectively use

Irrigation requirement can be computed when ET is known by using:

I = ET - Pe + Ro + Dp + L (4-5)

where: I irrigation requirement [mm/day]

ET evapotranspiration [mm/day]

Pe effective rainfall [mm/day

Ro run off due to irrigation [mm/day]

Dp deep percolation due to irrigation [mm/day]

L leaching requirement [mm/day]

In this study, the irrigation requirement is also computed by using CROPWAT 7.0 for the whole system CROPWAT does not take into account leaching requirement and groundwater contribution to the soil moisture zone (FAO of the UN, 1992) Because the fields in the system are designed as rice fields bordered by bunds, the horizontal runoff does not occur Therefore, leaching requirement, L, and run off, Ro, in equation (4-5) were cancelled To obtain monthly irrigation requirement for the whole scheme, the input data needed are crop coefficient, planting date and percentage of planting area for each crop (FAO of the UN, 1992)

CHAPTER V ANALYSIS, RESULTS AND DISCUSSION

5.1 Service delivery performance indicators

5.1.1 Reference evapotranspiration

1 Climate

The general climatic condition of the Vinh Phuc province falls under category of tropical monsoon climate It is influenced primary by the seasonal monsoons, namely Northeast (NE) and the Southeast (SE) the monsoons The NE monsoons in the dry season normally occurs from mid October to April The characteristics of this period are less amount rainfall, lower humidity and less cloudiness The SE monsoons in the rainy season generally from May to September It is period of frequent and heavy rainfall, high relative humidity and cloudiness According to statistical data, more than 80% of annual rainfall falls in this period

Climatic parameters were taken from the record of Vinh Yen town weather station, this station is located at the center of study area The study duration is 5 years (1998-2002) The average monthly value of climatic parameters of the study area is shown in Table 5.1 In addition, more detail value of the climatic parameters can be found in Appendix I

Table 5.1 Average monthly value of climatic parameters

Month Rainfall

(mm)

Maximum temperature (P

o

P

C)

Minimum temperature (P

o

P

C)

Relative humidity (%)

Wind speed (m/s)

* Source: Vinh Yen weather station, 1998-2002

Table 5.1 indicates that the rainfall is distributed unevenly throughout the year The mean monthly rainfall varies from 17.7 mm in February to 270 mm in June The average maximum temperature varies from 20.9oC in February to 33P

o

P

C in July while average

monthly relative humidity value is rather high, it varies from 78.1% in November to 87.7

in March The wind speed varies from 1.4m/s (min) in August to 2.0 m/s in February (max)

Total rainfall of each year (1998-2002) is shown in Table 5.2

Table 5.2 Total rainfall

Total

rainfall(mm)

822.4 1338.6 1199.2 1622.8 1418.4 1280.3

The Table 5.2 shows that amount of rainfall varies from minimum value of 822.4 mm in

1998 to maximum value of 1622.8 mm in 2001 Mean amount of rainfall in duration 5 years is 1280.3 mm

2 Reference Evapotranspiration ETo

ETo is determined by using CROPWAT 7.0 The Table 5.3 shows the calculated results

of ETo for every month of study area during 5 years (1998-2002)

Table 5.3 Reference Evapotranspiration

5.1.2 Irrigated area under different crops

Lien Son system has 2 planting season every year Rice is cultivated as major main crop about 90% total area Maize and soybean also are cultivated with considerable area

Other crop is considered negligible compare to the three main crop Table 5-4 shows the summary data of the irrigated area under different crops In addition, more detail value can

be found in Appendix II

Table 5.4 Irrigated area under different crops

Figure 5.2 Crop calendar The Figure 5.2 shows that for dry season rice, the time of sowing rice seeds is at the end

of December and harvesting date is at the end of April, while calendar for wet season is from middle of May to beginning of September For maize in dry season, transplanting date is at the end of January and harvesting date at the end of May, as wet season, respectively time is from middle of June to end of September While, calendar of soybean

in dry season begin at the end of January and come to end at the beginning of June, the last calendar for soybean in wet season is from end of June to beginning of October

There are no crop cultivated at the left time of year

5.1.3 Irrigation requirement

* Effective rainfall

Effective rainfall of the study area in the period 1998 to 2002 is calculated by using equations (4-3) and (4-4) as follows:

Pe = (125 - 0.2 * Pmon)* Pmon/ 125 for Pmon < 250 mm/month) (4-3)

Pe = 0.1 * Pmon + 125 for Pmon > 250 mm/month) (4-4)

in which

Pmon: monthly rainfall (mm)

The calculated results are shown in Table 5-5

Table 5.5 Effective Rainfall

Considering the copping pattern and effective rainfall, irrigation requirement in mm/month for the whole scheme can be calculated and shown in Table 5.6 More detail irrigation requirement for each crop and planting date is represented in Appendix III

Table 5.6 Irrigation water requirement

is much higher than compare to correspondent value of the year 1998 (refer to Table 5.5)

5.1.4 Water supply

Surface water supplied to Lien Son Irrigation system is taken through Lien Son diversion

and Bach Hac pumping station Statistical data of duration 5 years (1998 – 2002) is

Lien Son

Bach Hac

Lien Son

Bach Hac

Lien Son

Bach Hac

Lien Son

Bach Hac

Feb 10.2 20.4 10.9 19.4 18.3 13.86 18.41 16.99 18.4 4.46 Mar 20.8 12.53 11.8 19.9 26.78 5.97 25.4 1.336 18.87 4.024 Apr 30.5 11.34 13.2 13.8 18.92 15.3 21.35 6.512 21.82 5.77

5.1.5 Over all efficiency

The over all efficiency is ratio of irrigation water requirement and total inflow into canal system It indicates how many percent of water used actually by crop from total water

supply Table 5.8 shown these value throughout years

Table 5.8 Over all efficiency

Year

Irrigation water Water supply Over all

efficiency Requirement (10P

Table 5.8 and figure 5.2 indicate that in general the overall efficiency of Lien Son system

is in range from 0.594 to 0.616, it mean that about 60% total water supply is used by crop and 40% lost in processes delivery, distribution and application of irrigation This performance indicator is rather good because of canal network of system has been lined rather much (refer to 2.7)

5.1.6 Annual irrigation water delivery per unit irrigated area

The AIWDPUA depend on irrigation requirement and ability of supply of water sources These values of duration (1998-2002) are shown in Table 5.9

Table 5.9 Annual irrigation water delivery per unit irrigated area

0 2,000 4,000 6,000 8,000

5.2 Productive efficiency indicators

5.2.1 Gross annual agricultural production

Planted area, productivity, yield of each crop and gross agricultural production of

duration 5 years (1998-2002) is show in Table 5.10

Table 5.10 Total crop Area, Productivity and Yield

season Rainy season

Dry season Rainy season

Dry season Rainy season (ha)

From Table 5.10, we can see that the crop productivity and yield in study area increase year to year while total area are stable or even decrease approximate 2,000 ha in 2002 Examples, for rice in dry season, crop productivity increases from 3.55 ton/ha in 1998 to 4.67 ton/ha in 2002 while yields increase 15,799 tons from 72,011 tons (1998) to 87,810 tons (2002), equivalent 21.9%, then maize respectively are 2.60 ton/ha to 3.35 ton/ha of crop productivity and 5,383 tons to 6,332 tons of yield Total yield of rice of 141,826 tons

in 1998 increased to 170,214 tons in 2002, different amount is 28,388 tons

5.2.2 Total annual agricultural production

Yield, local price and total agricultural production of duration 5 years (1998-2002) are shown in Table 5.11

Table 5.11 Total annual agriculture production

Local price* Production Yield

Local price* Production (ton) (VND/ton) (1000VND) (ton) (VND/ton) (1000VND) (ton) (VND/ton) (1000VND) (1000VND) (USD)

The Table 5.11 indicates that although the crop yield is increased year after year, but total production decreased from 24,084,644 USD in 1998 to 19,038,606 USD in 2002 because of local market price of crop production come down In 1998, local price of rice

is 1,850 VND/ton while it is only 1,600,000 VND/ton in 2002, even 1,550,000 VND/ton

in 2001 Similarly, local price of maize and soybean are decreased also

5.3 Financial performance indicators

5.3.1 Total number of personnel

Total number of personnel of districts and whole company is shown in Table 5.12

Table 5.12 Number of personnel

Unit: person

P

Year Mong Tam Vinh Yen Binh Vinh Offical Total

Cau Duong Tuong Lac Xuyen Yen Center

5.3.2 Irrigated area per person unit

Table 5.13 Irrigated area per person unit

Unit: ha/person

P

The Table 5.13 indicates that there are big difference of irrigated area per person unit between districts The average value of Binh Xuyen district is 342.60 while Vinh Yen is