Master of Engineering Thesis: Performance evaluation of the Lien Son Irrigation System, North Vietnam

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PERFORMANCE EVALUATION OF THE LIEN SON IRRIGATION SYSTEM, NORTH VIETNAM

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 Development/DANIDA,

Asian Institute of Technology School of Civil Engineering

August, 2004

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Irrigation performance indicators, which comprise engineering and economic indicators, allow an assessment on performance of itrigation 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 irigation performance indicators have been proposed over the years. But they still receive relatively litle use, and that use is mostly by researchers rather than managers. Aecording to Nelson (2002), each irrigation community needs to select a ‘group of key indicators, that are applied offen 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 itrigation 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 irigation performance for the study area,

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1 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. [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 facilites throughout my study.

[also would like to thank to all members of the Vinh Phục 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 ftiendship. 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

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1.2. Need for study

13 Objectives and scope of study.

CHAPTER II DESCRIPTION OF STUDY AREA. 2.1. Location and area,

2.2 Climate and hydrology. 23. Topography and soil 24, Land use,

2.5. Crop cultivation

2.6. Irrigation system and facilities. 2.7. Present operation and management

CHAPTER II LITERATURE REVIEW,

CHAPTER IV MEDOTHOLOGY.

4.1. Benchmasking in the Irrigation and Drainage sector. 4.2, Data collection and analysis,

4.2.1. Data collection 4.2.2, Data processing

CHAPTER V__ ANALYSIS, RESULTS AND DISCUSSION, 5.1. Service delivery performance indicators

5.146 Annual irigation water delivery per unit irrigated area, 5.2. Productive efficiency indicators

5.2.1 Gross annual agricultural production 5.2.2 Total annual agricultural production, ‘5.3 Finalcial performance indicators

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5.3.1 Total number of personnel 5.3.2 Imigated area per person unit 53.3 Total costs

5.3.4, Maintenance Budget Ratio 5.3.5 Personnel Cost Ratio 5.36 Cost of ierigated area unit 5.3.7 Total water fee collection

5.3.8 Water fee collected per irrigated area unit 5.3.9 Ratio of water fee collection per

CHAPTER VI CONCLUSIONS AND RECOMMENDATIONS, 6.1, Conclusions

6.2. Recommendations

Appendix I Climate Data Appendix IL, Crop Data Appendix II. Cropwat output

Appendix IV, Curreney exchange rae

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LIST OS TABLES

Table Title

‘Table 2.1; Area distribution on elevation. ‘Table 2.2. Number of cooperatives.

‘Table 2.3. Percentage of Production yield as water fe.

‘Table 2.4. Total budget received by LIMC from Vinh Phuc PPC.

‘Table 4.1: Data and information for evaluating indicators Table 4-2: Data processing.

‘Table $.1: Average monthly value of climatic parameters Table 52; Total rainfall

Table 5.3: Reference Evapotranspiration ‘Table 54: Irigated area under different crops

Table 5-5 : Effective Rainfall

‘Table 5-6: Irrigation water requirement

‘Table $.9: Annual irigation water delivery per unit irrigated area ‘Table 5.10: Total crop Area, Productivity and Yield

‘Table 5.11: Total annual agriculture production, ‘Table 5.12: Number of personnel

‘Table 5.13: ligated area per person unit. ‘Table 5.14: Total costs

‘Table: 5.15: The Maintenance Budget Ratio. ‘Table 5.16: The Personnel Cost Ratio

‘Table 5.17: Ratio of total cost per irrigated area ‘Table 5.18: Water fee collection

‘Table 5.19 ; Water fee collected per irrigated area unit ‘Table 5.201: Ratio of water fee collection per total cos.

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Figure Title

igure 2.1. Map of the study area Figure 5.2: Crop calendae,

LIST OF FIGURES:

Page

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'REVIATION AND SYMBOLS

A slope vapour pressure x ppsyerometrie constant A ‘Arca

ACIAR Australian Centre for International Agricultural Research,

Ai “Area cropped by crop i

CROPWAT (Crop water requirement

Dp Deep percolation

(ea-ed) Vapor pressure deficit

FAO Food and Agriculture Oganization

ET Evapotranspitation

B10 Reference crop evapatranspita a Soil heat flux

icp International Commission on Inigation and Drainage

IPTRID. ‘The International Programme

for Technology and Research in Irigation and Drainage

IWMI International Water Management Institute

MOM ‘Maintenance, operation and management

Pe Effective rainfall Pmon Monthly rainfall

PPC Provincial People Commitee Rn Net radiation at erop surface

RRD Red River Delta Rs Radiation

Tmax ‘Maximum temperature

Tin Minimum temperature “ Wind speed at 2m height Yi Yield of crop i

we World Bank

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CHAPTER L INTRODUCTION

1.1. Problem identification

‘With increasing population and demand for food, sustainable production increase from invigated agriculture must be achieved. With limited freshwater and land resources, and increasing competition for these resources, imigated agriculture worldwide must improve its ullization 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 leam how irrigation systems are performing relative to cách other and what the appropriate targets for achievement are.

With about 80 millions inkabitants and 331,700 square kilometers total area, of which ‘one third only is covered by plains, the iigated agriculture in Vietnam has become one ‘of the major sectors in the national economy and food security strategy. Inigation water ‘management thus has enormous economics implications for this country. While the structural infrastructure for itrigation- 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. Developm 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 inigation water management in developing country — at both macro as well as miero level

<small>= will ead to significant economic benelits.</small>

In most of the irrigation system in the North of Vietnam, water is increasingly becoming 4 scare resources duc tothe pressure frominereasing water requirement. In addition, due to change climate, the serious deforestation in the watershed, ete, 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 irigated 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 efficieney, 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

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inrigation systems are: a) many of them had been operated for years, but insufficiently rehabilitated; b) investment for irigation 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 exop productivity (ACIAR, 1999),

‘The Lien Son Imigadon 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, fom Pho Day river at the Lien Son diversion. The system started operation in 1917 with initial itrigation area of 17,000 ha. In 1962.the Bach Hac pumping station with capacity

of 11.2 m/s was constructed, it take Water from Red River for supplying water to system

«and the irrigated area of system was expanded up 10 23,000 ha,

In recent years, many rehabilitation projects for the Lien Son irigation 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 i?

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

<small>system management,</small>

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

4) Collection data: Including data of hydrometeorology, crops, irigation management costs, water fee,

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

timating of data: Caleulate crop water requirement, irrigation requirement,

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

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

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CHAPTER II

DESCRIPTION OF STUDY AREA 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, Bình Xuyen and Vinh Yen town of Vinh Phuc Province, I is within the longitude of 104955" to 106012) ast and the latitude of 21912" to 21948" North. The system has boundaries with Tam

Dao mountain at the North and North-East, Hanoi city atthe 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 inthe economic development of the Vinh Phúc 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 t0 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 9C, the hottest month is July in terms of

monthly mean temperature(28.79C), and the lowest isin January (16.2 °C). The annual relative humidity i high, as 84.5%

‘The prevalent wind direction in winter season is North-East with average speed of about 200 ns. The prevalent wind direction in surnmer season is South-East with average speed ‘of about 1.8 ms, Typhoons and storms occurs in the rainy season from July to October.

There are about 5.5 typhoons landed in 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 mỔj (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 km) 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 ofthe Pho Day river atthe Lien Son sation as Following

In dry season: Max discharge of 11 m/s to 13 m3/sin April and min of 4.5 ms 10.6.0 Ss in March

= In rainy season: Max discharge of 60 m¥/s to 83 mis in une and min of 12 miso 15

Ôn September.

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Figure 2-1; Map of study area

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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 mabove the MSL, in ‘which 57.49% of area is from 48 to +11 m above the MSL. The cultivated land, build up by alluvial soil of Redriver, i light loamy sand. The low land near by the rivers are giay for medium loam, The high land near by the mountain or hill are feraliúc. Area distribution on elevation are shown in table 2.1

‘Table 2.1: Area distribution on elevation

No. Elevation (m) ‘Area (ha) Percent (59)

“The study area with 6 districts which have 23,000 ha of agricultural land of which 20.400 hha 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 dy season hecause itis 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 Phục statistical Department) 3⁄5. Crop cultivation

In general, the crop yield of study area isa lite bit higher than the national average yield "The cropping intensity inthe area is 1.98.

Rice (paddy)

Rice is the staple food crop in the study area, providing the people with about 80% of carbohydrate and 35% protein imake

According to statistical data (Vinh Phúc statistical Department, 2002), average rice yield (of study area(4.67 tons/ha) exceeded the yield capacity of national level (4.4 tonvha) in which Vinh Tuong district occupied the highest yield (5.50 tonsfha) and Mong Cau is the lowest (4.07 tonvha), However, rice yield remain relatively low compared with neighbor

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provinces in the Red river Delta, such as Ha Tay and Thai Bình provinces has raised rice yields to more than Š tons/ha/erop.

i has two erop 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 tonsa, in which Vinh Tuong district occupied the highest yield (3.9 tondha) and Vinh Yenis the lowest (3.0 tons/ha),

TL has 1wo crop seasons a year: sp and summer-autumn soybean as maize t00, Yen

supplied by two head works of Lien Son diversion and bility to supply in dey ‘The irigation inthe study are

Bach Hac pumping station, in which Bach Hac has main resp 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 LOSm, ‘comprises 3 spans, height of 5.l6m, the elevation of spillway is 21,13m. Its design ‘migation 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 m/s

2, Bach Hae pumping station

Ie was built up in 1962, take water from Red river. Capacity of pumping was designed of

112 m3/s with 6 units in which of 2.225 m3/s Amit, Head of design is 9m. As survey in

2001, it was sil in good performance

<small>3, The canal system:</small>

[A the present, the canal system of the study area isin good condition because almost of canal fom main canal to on-farm canal has boen lined by concrete or brick from 1995 to present. Tn this area, 86km of main anal, 263 intake structure and 13 secondary canal, 294 over level slices and many other structure such as siphons, divert slices, checks, drops, transitions,

‘Main canal: At the end of 2002, 74 kmlined by concrete of total 86 km. The width of bottom changes from 2.5 m at the end to 11.5 mat the head of eanal. The average bed

slope is 210-4

‘Secondary canal: 13 ones with length of 3.9.5 km, the width of bottom is from 3 to 10m, inrigation service area of each canal is about 200-1500 ha, about 70% lined (counted at the end of the year 2003).

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

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

i has total 11 local pumping stations with capacity of 1000 to 2500 mỔ/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 irtigation system in the study area is operated and managed by the Lien Son inigation management company(LIMC) as state company of the Vinh Phục 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 activites

‘The central office is responsible to administrate main activites 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 Tương, Yen Lac and Binh Xuyen. The sub-company is responsible for irrigation, drainage in each area of distrit, Each sub-company has a set of irrigation group, each being responsible for about 1000 ha. The irigation 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 ofeach district is given in Table 2.2

Table 2.2. Number of cooperatives

District Mong Tam | Vinh YenLac| Binh | Vinh | Total

Cau Duong_| Tương Xuyen | Yen

Number of 8 23 | 4 sa | 9 | 150

‘The water fee are estimated based on average production yield and water supply condition. Water fees are determined by percentage (%) of average production yield as stipulated by Provincial People Committee (PPC). These percentage for different water supply condition in dry and wet season are given in Table 2.3.

‘Table 2.3. Percentage of Production yield as water fee

No._| Water supply condition Dry season Rainy season 1, |= Inrigated by gravity from Lien 4-65 % 355%

Son diversion

2._|-Irigated by pumping stations 5158 465%

‘Water fees are reduced by half for farmers who get water from the ierigation system but have to use portable pumps- or manual lift with a scoop handled. Inthe study area, water

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is supplied directly by gravity into farmer Fields of about 60% irrigated area and about 40% ofthe 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 sation, 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 oF ân kind. Standard of water fee amount ranges from 380 kg/halyear in Tam Duong district 10644 kgfha/year in Vinh Yen district.

he central office manages the financial and personnel affairs of company. All costs (calary, 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 forthe Irigation Management Company based on report. submitted. Table 2.4 shows total budget which LIMC has received from Vinh Phục PPC during Š years * Source: Lien Son Irrigation Management Company

~ Currency exchange rate: Appendix 4

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CHAPTER IIL LITERATURE REVIEW

[Nelson et al. (2002) provided a set of performance indicators for itrigation 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 erop yields that are also affected by other factors. Indicators also oriented toward the existing system, aspects which do not requize major modification of the infrastructure,

Peter et al. (2002) summaries the background to irrigation water provider benchmarking in Australia, summaries why the tigation providers participate in the annual benchmarking report, outlines what has been achieved by providing the benchmark 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 T8 imigadion 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 irigation and drainage benchmarking exercise

Sakthivadive etal. (1999) introduced comparative performance indicators that make it possible to see how wel irrigated agriculture is performing atthe system, basin or

c performance of irigation 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,

<small>‘+ Inigation managers to identify long-term trends in performance, to set reasonable</small>

‘overall objectives and to measure progress.

‘+ Researchers to compare irrigation systems and identify factors that lead to better performance,

Kioezen 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

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environmental performances of irrigation systems. The aim of applying comparative indicators is to evaluate outputs and impacts of imigadon management practices, imerventions across different systems and system levels, as well as to compare various itrigation 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, asa consequence, enable them to identify

‘gaps in irrigation management policies. Generally, process indicators are used to assess

Actual irrigation performance relative t0 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 ate 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 imigation managers can use in assesing

performance of itigation 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 40 improve performance

Bos (1997) summatied the performance indicators currently used in the Research Program on Irrigation Performance. Within program field data are measured and collected 10 quantify and test about multidseiplinary performance indicators. These indicators cover water delivery, water use efficiency, maintenance, sustainability of 3, environmental aspects, socio-economics and management. The indicators now are sufficiently mature to be recommended for use in tigation and drainage

performance asses!

‘Small (1996) gave an overview of Imigation operation and maintenance in Vietnam ‘under economic restructuring Institutional and financial considerations. Vietnam's, policies to establish a market economy are reshaping the slate or

agricultural cooperatives that have operated and maintained irigation systems. The new Policies emphasize financial autonomy for state enterprises, and a shift in the responsibiliies of the agricultural cooperatives away from collective production activities. Specifi 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 iigation 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 st lerprises have partial financial

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‘autonomy, financing their activities primarily from itrigation fees collected fom 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 aze faisly high by ‘comparison with other Asian countries; however they are lower than typically paid by

farmers in the small pump irigation schemes operated by the agricultural cooperatives. Lank Ford & John Gowing (1995) provided a method is presented to analyse the impact ff the selection of irrigation gates on operational performance of the Sungai Muda Invigation 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 hydromodile isthe reciprocal of "waterduty” and thus has units of litressecond/hectare. The greater the deviation between the (wo, the greater the potential loss of conol 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 tumout 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 irigation schemes, the operational implications of design approximations should be examined more carefully.

Makomb et al. (1998) analysed the water management performance of small holder itrigation 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 cttor committed by each system in tying 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 irigation development in Zimbabwe.

Small & Rimal (1995) Based on a simulation model reflecting physical and economic conditions typically foun tion systems in As ierigation 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.

Inigation ‘performance is evaluated using several efficiency measures reflecting the physical, agronon-de and economic productivity of water, and one measure of equity.

Economic efficiency and equity among farmers within the portion of the irigation 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

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‘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 is 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 distibution 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 lo maximize

<small>{economic efficiency.</small>

Zalidis etal, (1997) provided a method for estimating of a network irrigation efficiency {0 cope with reduced water supply. The overall itigation efficiency, ep, forthe irrigation networks in the Thessaloniki plain, in Norther Greece, was estimated from historical data, spanning eight years. Irigadon networks differ regarding the method of water delivery and the method of Field application.

Overall irigation efficiency is the parameter which helps to adjust water supply to meet the actual erop water requitements. A method is introduced which calculates networks ep using spatially distributed data. Ehciency 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 018 1. Anaiysis ofthe time series ep values ean identify operational factors that might affect network ep. Sprinkler and surface network irigation 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 cdteria common to ‘many inrigation systems are suggested. A format for describing these and other ‘maintenance activities is proposed. A methodology for setting decision levels for ‘maintenance activites is presented. Maintenance cost is compared with incom last 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 Mexible 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 inrigation 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 efficieney must improve. A flexible irrigation water supply can lead to improved efficiencies. Non-point-source pollution and in-stzeam 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 ‘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 envizonmental benefits,

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FAO (1990) provided Guideline for computing crop water requirement.

‘This publication presents an updated procedure for calculating reference and crop cevapotranspiration from meteorological data and crop coefficients. The guidelines are intended to provide guidance to project managers, consultants, irigation engineers, hydrologists, agronomists, meteorologists and students for the calculation of reference and crop evapotranspiration, They can be used for compating crop water requirements for both imigated 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 57, 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 cootains 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 pattem) and results (crop water

requirements, soil moisture deficit) can be drawn and printed with ease. Complex cropping pattems can be designed with several erops 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,

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CHAPTER IV METHODOLOGY

41. 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 Inigation and Drainage (ANCID) on 33 imigaion systems and used 15 performance indicators and the 1998/09 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, WML 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

NG.[— Indicator Data need Frequent | Source | Note

+ Service delivery

1 | Total annual volume | * for calculating evaporation |aonghly | Vin _ oferopidigadon — | bY FAO Cropwat: ret

tang ~ rainfall, ae temperature, air Station and humidity, wind speed, sunshine AD

~ average percolation rate

<small>~crop coefficient</small>

<small>area planted to each crop</small>

<small>2 | Total annual volume | Daily average discharge at Atleast | Lienson Suy</small>

ofirrigation water | Lienson diversion and Bachhae | twice/day_| Irrigation inflow pumping tation management

Lic

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'Toialannual volume | Inflow at Lienson diversion and [annual |[LIMC — of total water supply | Bachhac pumping station

<small>+ daily rainfall at Vinhyen</small>

‘meteorological station discharge pumping from groundwater

‘Total annual iigated | - Imigated crop area for each | annual | LIMC and | Secondary crop area individual crop of 2 season set, Agricultural

and dey Departments

Gross annual -Plamted area ofeach erop and | Annual” | LIMCand | Secondary agricultural crop yield crop AD

Total annual “Local price of each crop Every [LIMC and | Secondary agricultural “Currency exchange rate season | AD

production Financial

Total number oF ‘Number personnel oF station and | annual [TIMC Seven

personnel engaged in | center office I&D service

Tnigated area per bal person unit

= Bulk water fee amual [TIM Sun.

‘Total MOM* cost <small>= staff cost</small>

<small>= operation cost (electricity for</small>

‘operation pumping station and

Personnel Cost Ratio Ratio of cost and inrigated area

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Gross water fee costs for cultivated plants Every [LIMC and | Secondary

collected = yield of erop season | AD

= local price of erop productions

Water fee per „ inrigated area unit

Ratio of water fee ~

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

No. Data need Processing Unit

1 = Monthly (afar VETu, = X(Etc, - ReJAv ms temperature, air humidity,

wind speed, sunshine hour...)

VET. = Total volume of water consumed by crops less effective

rainfall (my

+ average percolation rate i =Crop ype

‘+ crop coefficient Ke Ete; = Evapotranspiration from

+ meaplanted each crop | et ! am plating to harvest

ti) Geference the falling

R= Bletve rfl ver cap

area from planting to harvest (m')

A, = Area planted 0 op i

2 Imgated crop re foreach ote stem area in each season and | bà individual cop of2 euons va dy | whole year

3 [-tntow at Linson diversion and | Agetegsteup for evry yar nơ Baca pomping sao each

5Í - 8ađeng Ageegueup foreach daulosaml [USS

<small>+ Operation cost (electricity for | whole company</small>

operation pumping station

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6 | Salary, bonus, cost for travel,.of | Aggregate up for each district and uss personnel at districts and center | whole company

1. Crop water requirement

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

uring its growth, crop requires water for digestion, photosynthesis, transport of mineral and photosynthesis, structural suppor, growth, and evapotranspiration, Because other wse reeds very smull 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 hhypothetic crop with an assumed crop height of 12 em, a fixed canopy resistance of T0

ml 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

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where: ETo reference crop evapotranspiraion [mnv/day] R net radiation at crop surface [M/ m"/day] g sol heat flux [MU mẺ /day]

T average temperature [° C]

1 ‘wind speed measured at 2m height (mvs) (exed) vapour pressure deficit kPa]

a slope vapour pressure curve [kPa"C] ñ psychometric constant [kPaFC|' 900 ‘conversion factor

Crop water requirement can be calculated by equation:

ETo*Ke 42) where:

ETo reference crop evapotranspiration [mnvday] Ke: crop coefficient

‘The crop coefficient of a particular crop depends on erop characteristics, time of planting, stages of crop development, ength of growth season and climatic conditions.

‘The crop growth duration consists of four main stages, which 1) Initial stage

2) Development stage 3) Mid season stage

<small>4) Lae season stage</small>

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

In this study, ETo and BT will be computed using CROPWAT (FAO of the LIN, 1992) CROPWAT isa decision support system developed by the Land and Water Development,

Division of FAO. Its main functions we (1) to calculate reference evapotranspiration, crop water requirements and crop ittigation requirements, (ji) to develop irrigation Schedules under various management conditions and scheme water supply, and also (i) to evaluate rained production and drought effects and efficieney of irigation practi

‘The CROPWAT is meant as a practical 1001 to help agro-meteorologists, agronomists and irrigation engineers to earry out standard caleulations for evapotranspiration and crop water use studies, and more specifically the design and management of imigation schemes. It allows the development of recommendations for improved irrigation

practices, he planning of irrigation schedules under varying water supply conditions and

the assessment of production under rained conditions or deficit irrigation,

‘The calculations of erop water requirements and isigation requirements were carried out with the inputs of climatic and crop data, The development of irigation schedules and evaluation of rained and imigation 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,

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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 S7 version. CROPWAT for WINDOWS contains a CROPWAT version in Visual Basie to operate in the Windows environment. It has been developed with the assistance ofthe Intemational Irigation and

Development Insitute (IIDS) ofthe University of Southampton, UK (Clarke, 1998) In this analysis, CROPWAT 70 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 oquirement For tice 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,

1. Temperature

‘The daily maximum and minimum air temperatures in degrees Celsius (°C) are required ‘Where only (average) mean daily temperatures are available, the calculations can stil be executed but some underestimation of ET, will probably occur due to he non-linearity of the saturation vapor pressure -temperatue relationship,

2. Humility

‘The daily actual vapor pressure, ca, in kilopascals (kPa) is required. The actual vapor

pressure, where not available, can be derived from maximum and minimum relative

húmidi (%), psychometric data(dry and wet bulb temperatures in OQ or dew-point temperature [C)

3. Radiation

‘The daily net radiation expressed in megajoules per square meter per day (MJm day”) is,

required. These data we not commonly available but can be derived from the (average) shortwave radiation measured with a pyranometer or from the (average) daily actual duration of bright sunshine (hours per day) measured with a (Campbell-Stokes) sunshine recorder

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 sol 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 writen as:

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Pe = (125 -02 * Pmon)* Pmon 125 for Pmon < 250 mn/month) (4-3) Đe=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 sol profile, elevation of water table, sil permeability, depth ‘of impervious layer, and topography generally determine these natural phenomena. Paddy field, characterized by neatly 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

percolation of 6.096 mnv/day (WASCOS, 1983),

‘The estimates assume thatthe soil of the paddy’ is wet tlled prior to transplant

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 irigation requirement ofa crop is the total amount of water that must be supplied by imigation lo a disease-free crop growing in a large field with adequate soil water and feniity 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 irigation 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

T-Pe+Ro+Dp+L as)

where: I irrigation requirement [mmday] ET evapotanspiraion [mnvday|

Pe effective ruinfall [mm/day

Ro run off due to irigation [mnvday]

Dp ‘deep percolation due to irigation [mm/ay] L Teaching requirement [mmvday]

In this study, the ierigation requirement is also computed by using CROPWAT 7.0 for the whole system, CROPWAT does ot take into account leaching requirement and roundwater 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 docs not occur. Therefore, leaching requirement, L, and run off, Ro, in equation (4-5) ‘were cancelled. To obtain monthly irigation requirement forthe whole scheme, the input data needed are crop coefficient, planting date and percentage of planting area for each crop (FAO of the UN, 1992),

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CHAPTER V

IS, RESULTS AND DISCUSSION

S1 Service delivery performance indicators 5.1.1 Reference evapotranspi

1. Climate

‘The general climatic condition of the Vinh Phuc province falls under category of tropical ‘monsoon climate, Its 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 nerally from May to September. It is period of frequent and heavy rainfall, high lative humidity and cloudiness. According to statistical data, more than 80% of annual rainfall falls in this perio,

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. Inaddition, more detail value of the climatic parameters can be found in Appendix L

‘Table 5.1. Average monthly value of climatic parameters

Monh Rainfall | Maximum | Minimum | — Relative (mm) temperature | temperature | humidity (%)

* 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 177 mm in February to 270 mm in June. The average ‘maximum temperature varies from 20,99C in February to 33°C in July while average ‘minimum temperature varies from 15.49C in December to 26.8°C in July. The mean

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‘monthly relative humidity value is rather high, ít varies from 78.1% in November to 87.7 in March, The wind speed varies from 1.4mv/s (min) in August to 2.0 mv/sin February (max).

Total fall of each year (1998-2002) is shown in Table 5.2 ‘Table 5.2. Total rainfall,

yer | 1998 | 1999 | 2000 | 2001 | 2003 | average Total S234 | 13386 | 11992 | 16228 ID 12803

rainfall om)

‘The Table 5.2 shows that amount of rainfall varies from minimum value of $22.4 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 FTo for every month of study area during 5 years (1998-2002)

Table 5.3. Reference Evapotranspiration Mont ETo (mnvda

‘There is no big fluctuation of total reference evepotranspiration in study duration, the total ETo in a year varies from 1096.6 mmlyear in 2002 to 1201.1 mmwyear in 1998, ‘There are the same pattern of ETo throughout years it has usually minimum value in anuary or February and reaches to maxinum value in Tuly

5.1.2 Irrigated area under different crops

Liên 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,

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Other crop is considered negligible compare to the three main crop. Table 5-4 shows the summary data of the irigated area under different crops. Inaddition, mote deta value can

The Table 5.4 shows that rice area reaches to about 90% total cultivated area and rice area in rainy seasons are usually less than about 1600 ha compare to dry seasons due to flooding in rainy season. Maize area planted in dry season is more than 3-6 times in wet season while soybean area go to contrary direction. Crop calendar of erops is shown in

Figure 5.2. Crop calendar

“The Figure 5.2. shows that for dry season rice, the time of sowing rice seeds is atthe end ‘of December and harvesting date is atthe 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 erap cultivated atthe eft time of year.

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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:

‘The calculated results are shown in Tuble 5-5 ‘Table 5.5. Effective Rainfall

Jor Pmon < 250 mnvmonth) (4-3)

for Pmon > 250 mm/month) (4-4)

Month Effective Rainfall (mn/month)

There are big differences between total effective rainfalls throughout years. These values varies widely from minimum value 619.9 mm in 1998

effective rainfall of the year 1999 have approximate value to the year 2001

to 1018 mm in 2001. The

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 inrigation requirement for cách crop and planting date is represented in Appendix I.

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‘Table 56. Irrigation water requirement Irrigation water requirement (mm/month

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5.144 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 § years (1998 - 2002) is shown in Table 5.7

Table 5.7. Water volume derived to the system through Lien Son diversion and Bach Hae pumping station

*Source: Lien Son Irrigation and Drainage management Company

Unit: 1 mộ

Year 1998 1999 2000 2001 2002

Lien Bach |Liên [Bach Lien Bach Lien Bạch Liên | Bach Month Son Mac _| Son Hạc Son Hac __ Son Hạc Son |Hạc

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5.15 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 | - Imigaionwater Water supply Overall

‘Table 5.8 and figure 5.2 indicate that in general the overall efficiency of Lien Son system isin range from 0.594 to 0.616, it mean that about 60% total water supply is used by erop and 40% lost in processes delivery, distribution and application of irtigation. This performance indicator is rather good because of canal network of systems has been lined rather much (refer to 2.7).

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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 wi er delivery per unit itrigated area

Year | Water supply | Tota irigated | Water delivery

volume (I0 m) | aea(hwyea) | — (mÖ⁄hg,

From table 59 and figure 5.3, ít can be seen that the ATWDPUA varies in wide range

from 4,697 m/ha in 2001 to 7,938 mỔ/ha in 2001. Because of irigation requirement of

he year 1998 is Tess than muuch the year 2001 so that water supply is correspondent to meet water demand.

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,

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Table 5.10, Total erop Area, Productivity and. Yield

Bice Maize Soybean “Teta

Year tem ¡ Unt [OO Oy

‘season Rainy season | season Rainy season | season Rainy season — (ha)

sooo | Producty” | ona) 487 410 273 346 138 188

Viele (ton) | - 88088 TrAR | 5.577 1.208. 653 4101 Total on) 188573 6784 2254.

Arealha) (ha) | - 20488 18754| — 2083 398 346 929 4800 —.... 422 4.16 3.24 3.18 1.18 140

ve (on) | — 88459 78017 | — 6788 1,266 408 41301 Total (ton) 184 478 e034 1709

Arealha) (ha) | - 18808 18,900 1880 236 ase ana) 41488 aooe | Produativy’ | fonna) 467 4.36 9.95 327 128 167

<small>ve đen) | 87810 38404 | — 6832 88 418 1,880</small>

Total đen) 170214 7239 2278

“Source: Vinh Phúc province statistical Department

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From Table 5.10, we can se 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, fo rice in dry season, crop productivity increases from 3.55 1on/ha in 1998 to 4.67 toyfha 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 tonha to 3.35 ton/ha of crop productivity and 5,383 tons to 6,332 tons of yield. Total yield ofriee 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 product shown in Table 5.11

of duration 5 years (1998-2002) are

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Table 5.11. Total annual agriculture produeion

Rice Maive Soybean

Local Local Local ‘Tota produetion

<small>year | Yield | pret Production | Yield | price? | Production | Yield | prices | Production</small>

won) | (YNDjon) HI0DOVND) | (ton) (VNDHSm (HUOVND tim) | CVNen) | LoMDVND) wsb)

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“The Table 5.11 indicates that although the crop yiekl is increased year alter 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 erop production come down. In 1998, local price of rice is 1,850 VNDfton while itis only 1,600,000 VNDiton 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

Unite person Mong | Tam | Vinh | Yen | Binh | Vinh | Offical | Total

Ye" | “caw | Đương | Tương | tac | xuyen | Yen | Center

‘The Table shows that the number of personnel of whole company increase year by year from 184 persons in 1998 to 231 persons in 2002, in which 2 units supplemented much are Vinh Yen distit (11 up to 23) and central office (35 up to 53)

5.3.2 Irrigated area per person unit

Table 5.13. Irigated area per person unit

Unit: hajperson ‘Year| Mong | Tam | Vinh | Yeo | Binh | Vinh | Average

Cau | Duong | Tuong | Lac Xuyen - Yen

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

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