Luận văn optimal reservoir operation for water supply in dry season

MINISTRY OF EDUCATION AND MINISTRY OF AGRICULTURE AND THUYLOI UNIVERSITY Ly tk tt OPTIMAL RESERVOIR OPERATION FOR WATER SUPPLY IN DRY SEASON: THE CASE STUDY OF CUA DAT RESERVOIR IN TH

MINISTRY OF EDUCATION AND MINISTRY OF AGRICULTURE AND

THUYLOI UNIVERSITY

Ly tk tt

OPTIMAL RESERVOIR OPERATION FOR WATER SUPPLY IN DRY SEASON: THE CASE STUDY OF CUA DAT

RESERVOIR IN THE CHU-MA RIVER SYSTEM

THANH HOA PROVINCE

TRINH XUAN MANH

MSc Thesis

December 2014

case study of Cua Dat Reservoir in the Chu — Ma river system

Thanh Toa province

Master of svience lhesis

This research is finished for the partial fulfillment of requirements for the Master of seience

degree at Thuy Lot University, Ha Noi, Vietnam

(This Master Progranme is supported by NICHE-VNM106 project)

DECLARATION

I hereby certify that the work which is being presented in this thesis entitled, “Optimal reservoir operation in dry season: the case study of Cua Dat Reservoir in the Ma-Chu River system, Thanh Hoa province” in partial fulfillment of the requirement for the award of the Mater of Science on integrated Water Resource Management, is an authentic record of my own work carried out under supervision of Dr Nguycn Mai Dang

‘the matter embodied in this thesis has not been submitted by me for the award of any other degree or diploma

Date: ./12/2014

Water supply of reservoirs and especially reservoirs used for irrigation,

hydropower, aquaculture, navigation, environment the dry season are often

troubled due to increasing water demands according lo the economic development, and

society, while the flow to the reservoir is limited In recent years, the depletion of the river flow during the dry season occurs more frequently and at a more intense level This is partly due to forest coverage reduction in the upstream of river basins, and

partly due to the effects of climate change

Hence, computation of the optimum water supply of reservoir for the water

demands in the dry scason is needed, This study presents the initial rescarch on applying Fuzzy Logic Algorithm for optimal operation of water supply in the dry

season of 2011-2012 of the Cua Dat Reservoir in the Chu River basin, Thanh IIoa

province The Cua Dat Reservoir is a multi-purpose reservoir for the following tasks:

flood prevention, water supply, irrigation, power generation, and environmental flows

In addition, MIKE 11 model is also uscd to simulate the release from the reservoir to

the downstream to evaluate the efficiency of the optimal method

The research used Fuzzy Logic algorithm based on the rule, the principle of "IT

- THEN" and built the membership functions for the input variables: water level, inflow to the reservoir, the water demands, and discharge from the reservoir It is

developed for the Fuzzy operating systems for the Cua Dat Reservoir and is meant to determine the optimal discharge process in case of shortage of water in the dry season

Inflows, releases and water levels of the Cua Dat Reservoir were collected from actual operation of the reservoir For water demand of stakeholders, the author determined

that the total water demand for whole area was about 4547 Mim’ For hydropower

based energy production waler is used al the largest rae (67% of tolal water demand),

while domestic purposes water is obtamed smallest rate of water use of the Cua Dat

Reservoir

Finally, the results from optimal method, the reservoir can meet 80% of water

demand more than actual release throughout the dry season of 2011-2012 The initial

research has been successful and the tesully showed thal this method can be applied

well to the optimal reservoir operation in Vietnam,

Key words: Cua Dat, reservoir operation, optimization, Vuzsy Logic, water

demand, Fuszy rule, MIKE 1] model

Trinh Xuan Mank

MSc Thesis

Acknowledgement

First of all, 1 would like to give a big thank to all people wha have supported

and assisted me during the Master Thesis Research Thanks for their support,

encouragement and guidance (hat allowed me lo complete this study in time

Especially, | would like to express my appreciation to Dr Nguyen Mai Dang,

my supervisor, for his unlimited encouragement, guidance, comments and technical supports on the Fuzzy Logic approach and other models as well as the thesis writing process from the beginning of the thesis research

I would like to thank NICHE-VNM-106 project from the Government of the

Netherlands for their financial support during the MSc study in the ThuyLoi

‘University I thank to Mrs Iioang Nguyet Minh and Mrs Vu Thi Thuy Ngan who

made a linkage between me and NICHE I also would like to thank Assoc Prof Dr

Nguyen Thu Hien, Dean of the Favully of Waler Resources Engincering, for hor help and comments during the Master study in the ThuyLoi University

T wish to thank Dr Tyas Masih and Ms Martine Rutlen for their feedback,

references and support from the proposal process

L also wish to thank Mrs Mariette Van Tilburg, my English teacher, for her

comments and supporl from the final thesis report

I also want to thank the ThuyLoi University (TLU), Song Chu Lrigation

Company, National center for Lydro-Meteorological Service (IMS) for providing me

very useful data sets

‘Thanks to all of my colleagues at the HaNoi University of Natural Resources

and Environment in Vietnam for your assistance in the last two years You will always

CIIAPTER I: INTRODUCTIO!

1.1 Background

1.2 Problem statement “

13 Objectives and Rescerch questions

13.1 Objectives of the study

1.3.2 Research Question

TA, Structure of the thesis “

CHAPTER Il: LITERATURE REVIEW

ILL Studies on reservoir operation using optimal theory

12 Fuzzy logic theory

1.3 Overview of hydraulic and hy dtologicl modeing

LIL1 Description of the study 4rea cà not erireroee 13 TI11.1., Location of the study area - 13 IIL1.2 River network - 14 1111.3 Topographical characteristics - 16 UL.1.4, Geological, land and vegetable characteristics — -

TIT.2, Climate and hydrological condition

4.2.1 Climate condition sete

TIL.2.2 Hydrological condition -

11L3 Population and economic characteristics

11.3.1 Population of the study area

11L3.3 Eoonomic characteristics

TI.4 Descnphion of the Cua Dal Reservoir

CHAPTER IV: DATA AND METHODOLOGY

TV.1 Data collection

TV.1.1 Meteorological data

1V.1.3 Cua Dat reservoir operation data

IV.1.4 Determining total water demand

1V.2 Optimal analysis and Fuzzy logic approach for Reservoir operation sects 50

TV.2.1 Meiliodk ung in optimal reservoir operation - 30

TV.2.3 Using Fuzzy logic techmique to oplimiva the Cua Dal reservoir tr Ghemiion54

1V.3 Hydraulie and hydrological model setup - 62

TV.3.1 Determination of the model hạnh - - 62

1V.3.2 Model setup ¬ ¬— -

Trinh Xuan Mank

MSc Thesis

CHAPTER V: RESUI.TS AND DISCUSSIONS

Vii, Optimizing the Cua Dat reservoir operation

V.2, Routing the release to the downstream

CIIAPTER VI: CONCLUSIONS AND RECOMMENDATIONS

Figure 2-1: Relationship between the various representations of a model dO Figure 3-1: Location of study in the Thanh Hoa province in Viet Nam 13 Figure 3-2: Ma Chu River Network in Viet Nam 16 Figure 3-5: Digital Hlevation Model (DEM) of Thanh Hoa provinee „17

Figure 3-5: The main dam of the Cua at Reservoir 28

Figure 3-6; The spillway of the Cua Dat Reservoir 28 igure 3-7: The storage of the Cua I2at Reservoir Tre ¬-ˆ

Figure 3-8: The intake tower of the Cua Dat Reservoir 8

Figure 3-9: The gate of spillway of the Cua Dat Reservoir "-

Figure 4-1: Distribution of monthly rainfall pattern at Thanh Hoa station - 30,

igure 4-2: Distribution of monthly air temperature at Thanh Hoa station 31

Figure 4-3: Distribution of monthly average evaporation al Thanh Hoa station in 2011

Figure 4-4: Distribution of relative humidity al Thanh Hoa station mì 2011 & 2012 .32 Figure 4-5: Annual discharge of the Cam Thuy and Cua Dat station - 33

Figure 4-6: Schomalization of hydrological station network - 34

Figure 4-7 Monthly average discharge of Turbm o[ hyđropower plant i in years of

Tipure 4-8: Tnflow chacharge of the Cua Dal reservoir m 2017 and 2012, 35

Figure 49: Seasonal period and chart of waler requirement of Spring paddy in 2011 39 Figure 4-10: Scasonal period and chart of water requirement of winter paddy in 2011

4I Figure 4-11; Scasonal poriod and chart of water requirement of sugar cane m 2011 .42 Figure 4-12; Water use structure of whole downstream area of the Cua Dat reservoir in

igure 4-14; Fuzzy inference system for Fuzzy Mamdani

igure 4-15; ‘lransformation of input variable to membership value

Kigure 4-16, Membership function for reservoir level for Fuzzy Mamdani model

fïgure 417: Membership fuaetion for mflow for luzzy Mamadani rnodel 58 Figure 4-18; Membership function for water demand for Fuzzy Mamdani model 59 Figure 4-19; Membership function for release for Fuzzy Mamdani model „59 Eigure 420: Fuzzy rules base for operation of Cua LDak Tessrvoir sasssoosốD

Trinh Xuan Mank

MSc Thesis

Figure 4-21, Process of application, implication and ggrogation

Figure 4-22 Hydraulic network of the Ma Chu river basin

Figure 4-23, Observed and simulated hydrograph at Cua Dat station in 2006

Figure 4-24, Observed and simulated hydrograph at Cua Dat station in 2008

Figure 4-31: Structure of fizzy system for Cua Dat reservoir

Figure 4-32: Comparison of water demand and fuzzy and actual releases

Figure 8-1: Hydrograph of oplimal operation al the Bai Thuory, weir

Figure §-2: Hydrograph of optimal operation al the Xuan Khanh station

Figure §-3 Hydrograph of optimal operation al {he Giang station

Trinh Xuan Mank

MSc Thesis

‘Table 3-1: Distribution of natural areas according to provincial border of the Ma river

basin (ha) - - - 14

‘Table 3-2: Characteristics of river shape of some large tributaries « co 15 Table 3-3: Average annual rainfall for many years at some stations of the Ma river basin 19 Table 3-4: Annual rainfall characteristics - 20 Table 3-5: Monthly and armual wind speed at some stations of the Ma river banin (m/s)

21 Table 3-6: Avorage monthly temperature for many years at some slations 22 Table 3-7: Monthly average evaporation of some slalions of the Ma River Basin 22

Table 3-8: Some main parameters of the Cua Dat Reservoir

Table 4-1: Kinds of data have been used in the study 29 Table 4-2: Crop disinbution of different cultivated area in downstream of the Cua Dat

Table 4-3: Plant coctficionts of paddy HH HH He ngư „39

Table 4-S: Water requirement of Spring paddy in 2011 40 Table 4-6: Waler requirement of winter paddy in 2011 „41

‘Table 4-7; Water requirement of sugar cane in 2011 „43 Table 4-8: Monthly water demand of agriculture of whole arca in the Cua Dat reservoir

cdownstream in 201 1 c2 chư Hee ed 44

‘Table 4-9: Water demand of industrial ‘production at downstream of the Cua Dat

‘Table 4-LU; Domestic water demand of downstream area 6

‘Table 4-11: Structure of water use of whole area m 2011 AB

‘Table 4-£2: Water demands and inflows in ten-day period in 2011 AD Table 4-13: List of tributary basin on the Ma — Chu river basin 64

Table 4-14: Results of MIKE 1111D model calibration at Ma-Chu river basin in 2006

70 Table 4-15: Results of MIKE 111ID model validation at the Ma-Chu river basin in

Table 4-16: The NASII for calculation of alternatives ee TA

Table 5-1: Flow characteristics at the Chu River downstream using optimal operation

76

Trinh Xuan Mank

MSc Thesis

CHAPTERI INTRODUCTION

TA Background

Reservoirs play an important role in the development of many countries

Nowadays, there are many reservoirs and dams which were built im mi

ay developing

countries for various purposes, for example, water supply, flood control, electric

generalion, environment and recreation However, in 18" Century reservoirs were

built to supply water, flood control and navigation as the main purposes, atter that reservoirs were built for hydropower generation purpose by increasing demand for energy consumption of human,

As mentioned above, most of reservoirs are used for multiple-purpose All those purposes need to be satisfied but the capacity of reservoir is limited, For this reason some conflicts may happen among the water users who have other interests and conflicts also may bappen in reservoir itself For hydropower generation, higher storage of water is needed, on the contrary, much water should be relaesed for cultivated areas in dry season especially Besides this, there are also many other contlicts in uscr factors such as transportation and hydropower generation, flood control and environment ete

Vietnam has many big river networks with nine major river basing spread along the country At present, many multi-purpose reservoirs were built to serve the socio-

economic issues such as Cua Dat, Hoa Binh and Dau Tieng Reservoir ete The

Management and operation for many purposes are really difficull, On the other hand,

the operation of each reservoir is a challenge for management and operators Reservoir operation is needed to balance efficiently interests of water users and satisfy constraint

systems aim to gct maximum interests An optimal policy is necessary to accomplish

the problem objective and rule curve is one of appropriate methods to determine operation policy of reservoir Reservoir operation policy specifies the criteria to retain

or release water in or from a reservoir at different times of the year depending upon the

inflows and demands

Trinh Xuan Mank

MSc Thesis

Optimization model used the mathematical programming technique to find the best possible solution based on a specific performance function and some physical conshaints Mathematical programmmg includes several techniques such as dynamic progranuning (DP), nonlinear programming (NLP), linear programming (LP), genetic algorithms (GAs) and optimal control theory (OCT) (Hirad and Ramamurthy 2000)

Within the development of soft compuling tcchmque, optimal technique has been used in number water resources issues In this thesis, the author will use Fuzzy technique combine with hydraulic model to develop an operation policy for multi- purpose reservoir in an efficient way

12 Problem statement

Ma river basin is located in North-West region of Vietnam, it bordering Laos on the West, Ihe upstream basin is located in Vietnam, the middle basin is located in Laos and the downstream is located in Vietnam Accordingly, Ma river basin is an

international basin The catchment area of Ma river basin is about 31.060 Km? of

which that it Vietram is 20.190 Kin? (WRP 2003) The Chu River is a main tributary

of the Ma River It is located in the downstream area (TWRP 2003)

Rased on potential water resources of this river systema, many kinds of reservoir

such as single purpose and multi-purpose were built on the main river of the Ma river system The Cua Dat Reservoir is one of the biggest projects related to water resource projects in Thanh Hoa province The Cua Dat Reservoir is a multi-purpose reservoir Those purposes include as: to reduce flood peak and protect downstream area due to probability of flood of 0.6% and control water level in downstream area at Xuan Khanh slation on the Chu river (under 13.71m) in high flow season, To supply discharge of

7.715 m?/s for domestic and industrial water demand; ‘o imigate about 86.862 ha

cultivated area; To generate electricity with capacity of 97 MW: To prevent salt water intrusion lower than 1%e at Ham Rong measured station (MARD 2013)

As mentioned above, the Cua Dat Reservoir has purposes are to supply water for some water users such as hydropower generation, agriculture, industry, domestic and cuviromuent However, in dry season the iereasing water demand of waler users ia one of the important problems within water shortage in this river basin due to less rainfall will enhance the conflicts among all the factors In order to balance different

Trinh Xuan Mank

MSc Thesis

wator interests and solve the problems which related to using water, the Cua Dat reservoir needs to optimize reservoir operation

1.3 Objectives and Research questions

13.1 Objectives of the study

The main objectives of this research are:

- To optimize uperation of the Cua Dat Reservoir ist dry season, Thank Hoa province

by using simulation model (MIKE 11 model) and optimal model (Huzzy Logic Technique)

- To provide management recommendations or altematives and suggest appropriate

method of operation of the Cua Dat Reservoir inthe Ma Chu river basin

13.2 Research Questions

1 What is Fuzzy logic theory and how to apply fuzzy logic in reservoir operation?

2 Tow to balance the water demand and water interests of the stakeholders in

operation of the Cua Dat Reservoir?

3 What are the objective funchions and consbaints im operation of the Cua Dat Reservoir?

4 Does the Cua Dat Reservoir supply enough waler for all of sectors in downstream:

area regarding to current secnarios?

L4, Structure of the thesis

This thesis structure includes (hose parts as below:

Chapter 1: This chapter discusses an overview of the study, the problem statement and the objectives of the study are presented

Chapter 2 This chapter reviews several researches of optimal reservoir operation Overview of hydrological model and optimization formulation are presented MIKE 11 model also is briefly introduced in this chapter

Chapter 3: This chapter presents natural characteristic, natural conditions of the study as well as population and economic characteristics of the study Moreover, this chapter also briefly introduces characteristics of the Cua Dat Reservoir and water

demand of each water user in downstream area

Chapter 4: ‘his chapter describes all kind of data collection and data analysis

which are used in this study In this chapter, the author also shows the results of data

Trinh Xuan Mank

MSc Thesis

water user in the downstream area This chapter determines the objective functions and all of constraint systems in (he Cua Dat reservoir as well as using oplimization model

to determine optimal rule curve (standard mule curve) Hence, the author also presents MIKE 11 model set up for calibration and validation model and the results of routing Now from the Cua Dal Reservoir by MIKE 11 model in this chapter

Chapter 5: ‘the results of optimal model and simulation model are shown in this chapter through figures and evaluation tables The chapter also analyzes the results from two models m order to achicve the objectives of the study

Chapter 6: ‘This chapter also focuses on the main performances, conclusions and recommendations for future studies

Trinh Xuan Mank

MSc Thesis

CHIAPTERI LITERATURE REVIEW

LL Studies on reservoir operation using optimal theory

Optimization is scientific field about best choice in some possible alternatives Optimal theory has been developed and investigated for many years over the world Optimization has been applied to a lot of ficlds in human life Especially, in water resource issues are used optimal theory as one of the effective tools for management and decision making Furthermore, optimization techniques have become increasingly important in management and operations of complex reservoir systems in reservoir management, a lot of researchers have developed reservoir optimal operation during

the past four decades using dynamic programming (DP), linear programming (LP),

nonlinear programming (NLP), ote.(Cheng cl al 2008)

Rama and Sharad (2009) have developed operation policy for multi-purpose

reservoir in India using Neuro — Fury technique including Fuxyy Mamdani and

ANFIS (Adaptive Neuro Fuzzy Interactive system) Their research determined operation policy for monsoon period and non-monsoon period of Ramganga reservoir and optimum releases against demands for domestic supply, irrigation and hydropower generation In other research, Omid et al (2008) used optimal algorithm (HBMO-

Toney Bee Mating Optimization) for single and multi-purpose reservoir to minimize

the tolal present net cost of the syslem and maximum possible ratio for generale electricity with installed capacity In a case study of Hirakud Reservoir in Mahanadi basin, India, D_Nagesh Kumar et al (2009) used Folded Dynamic Programming (TDP)

to develop a long -term optimal operation policies for flood control He showed that

EDP is a new search technique which can take care of all difficulties of other methods

to certain extend faced

Long N.L et al (2007) presented successfully a method as a tool for optimizing operation of reservoir by using a combination of the simulation model and optimal

model The authors optimized control strategies for the largest reservoir in Vietnam,

Hoa Binh Re: crvorr, in order to neutralize the conflicls im regulating water bolweer

flood control and hydropower generation The authors also organized two main

purposes in the flood season Wilh simulation model, they used MIKE 11 to guide the

Trinh Xuan Mank

MSc Thesis

meteorological conditions, and the time of the year Afterward, the shuffled complex

evolution (SCR) algorithm was chosen as a porfeet tool for optimizing the reservoir operation, Babel et aL (2011) analyzed that the tradeoff between hydropower

production and environmental flow requirements for the hydropower system and the

impael, of allernalive scenarios of a hydropower system operation on energy production and natural flow regime in the La Nga river basin in Vietnam ‘the authors used different altemative operation policies to simulate the system by the Range of Variability Approach (RVA) method Hirad and Ramamurthy (2000) showed a now composite algorithm as an altemative model to solve the problem related to the size of reservoir when operating policy of multireservoir systems is applied based on Pontryagin’s minimum prineiple

Genetic algorithms have been widely applied in optimization to solve water resources system Cheng et al (2008) used Chaos Genetic Algorithm (CGA) which

based on the Chaos Optimization Algorithm (COA) and Genetic Algonthm (GA) to

apply to the global optimum of the Rosenbrock fimction, the Schaffer fimetion and the

oplinal operation of hydropower station reservoir, M-Habese, Y Nagayania (2002)

used Neural Network and Fuzzy Systom to optimize multi-purpose Dam of flood and non- flood seasons Base on their results, the fuzzy system is an effective operation

system when the major objcelive is water usc Besides thal Kelwork Fuzzy System is

effective for flood control In other research, fuzzy mathematical programming, was

used in research of Jairaj and Vedula (2001), their study area is a three reservoir system

in the upper Cauvery river basin, south China As the results lustrated that, use of fuzzy linear programming, in miulti-reservoir system optimization presents a potential

alternative to get the steady state solution with less efforts than classical stochastic

dynamic programming (Jairaj and Vedula 2001) Panigrahi and Mujumdar (2000) also used Muzzy Logie in their study to reservoir operation modeling, the case study of the Malaprabha irrigation reservoir in Karnataka, India

Besides that, there are many researches in reservoir operation in Vietnam They also used many optimization and simulation methods Nghia 1T (2009) used

combination method between optimization and simulation model within advanced tools

Trinh Xuan Mank

MSc Thesis

such as hydraulic dynamic model MIKE 11 and optimal technique GAMS The research had three majar contents as follow: i) Determining water demand of water

users (such as Tndusiry, Agricullurc, Navigation and Environment), ii) Determining

upstream constraints of system due to periods, iii) Propose the operation process for

three reservoirs including Thac Ba, Hoa Binh, Tuyen Quang based on optimal

calculation in order fo ensure Ghat multi-rescrvoir can supply cnough water for water

requirements in downsweam Hung N.'I et al (2010) proposed models for optimal operation of multiple purpose reservoir The research proposed three distinct altcrmatives including: i) Reservoir has mutual purpose for irigation and hydropower, ii) Reservoir's major purpose is hydropower generation and second is irrigation; iii) Reservoir has major purpose is irrigation and hydropower generation is second Based

on models of the authors were built by using Delphi programming language and applied Dynamic programming The models were applied on Dinh Binh Reservoir

(Binh Dinh province) and A Vuong Reservoir (Quang Nam province) In other Tescarch, optimization and simulation method were also used in the research of Tuyen MII (2009) for supplying water in dry season of reservoir system on Huong River

basin The research combined GAMS oplimization model and MIKE 11 hydraulic dynamic model to control flow in downstream The author illustrated that

environmental flow is about 31,5 m’/s in location of Thao Long Weir thoughout GAMS

optimal model In dry water year with probability of 90%, the reservoir system can still

ensure the lowest discharge into dowstream area is 75m‘Vs

Vinally, optimization theories have been applied in a number of water resources

issues, especially in ro

oir operation Fuzzy logic technique is one of the useful optimal tools for supporting reservoir operation and decision making Using optimization and simulation models in reservoir operation research are common over the world However, the Fuzzy Logic theory has boon never applicd in any rescarch about reservoir operation in Vietnam ‘Ihat is reason in this research the l’uzzy theory will be used a3 an optimization tool to optimize operation policy of Cua Dat Reservoir

thoughout objective function and constraints

Trinh Xuan Mank

MSc Thesis

According to Rama and Sharad 2009, the Fuzzy logic is another area of artificial infelligeree Tt has becn applicd successfully in different water resources applications

‘The key content about fuzzy logic theory is that it allows for something to be partly this

and partly that, rather than having to be either all this or all that The degree of

“belongirgness” to a sel or calegory can be described munerically by a membership number between 0 and 1.0 (Rama aud Sharad 2009)

In fuzzy logic theory, variables are “fuzzification” through the use of Membership Function (MF) that defines the membership degree to fuzzy sets These

variables are called linguistic variables A fuzzy subset A of a universe of discourse U

is characterized by a membership function wA(x) in the interval [0,1] and represents the grade of membership in A (Rama and Sharad2009)

The fuzzy objectives and constraints are characterized by their membership

functions Membership functions are curves that define how each point in the input

space is mapped to a membership value (or degree of memberslrip) between O and 1 Tt can be of different forms including triangular, trapezinm, Gaussian, B-spline, sigmoid

etc Membership function can be symmetrical or unsymmetrical (Rama and

Sharad2009)

Fuzzy rule base system can be used as a suitable representation of simple and

complex physical systems The fuzzy rule based model operates on an “IF-THEN”

ptineiple, where the “IF” is a vector of fuzzy explanatory variables or premises and

“IIIHN” is fuzzy consequence Fuzzy logic theory allows the user to capture

uncertainties im data A fussy tool is available with the MATLAB sofware Two Lypes

of fuzzy inference systems including: Mamdani type and Takagi Sugeno type

Fuzzy logic theory also has been used widely in modeling of reservoir

operation According to Panigrahi and Mujumdar 2000 when applying fuzzy theory need to follow several steps: (a) J*uzzification of inputs, where the crisp inputs such as the inflow, reservoir storage and release, are transformed into fuzzy variables, (b) Formulation of the fuzzy rile set, based on an expert knowledge base, (c) Application

of a fuzzy operator, to obtain one number representing the premise of each rule, (d)

Shaping of the consequence of the rule by implication, and (e) Defuzzification

Trinh Xuan Mank

MSc Thesis

Similarly, the Fuzzy logic will be used in this study for the Cua Dat reservoir operation And this is the initial research using the Fuzzy Logic in operating reservoir

m Vicinarn

LL.3 Overview of hydraulic and hydrological modeling

Any scientific field always need a developed process including monitoring data,

revording and measuring data, simulation and explanation of natural phenomenon Hydrology is a science of water on the earth ‘fo understand the hydrological events can be described in laboratory by physical models Based on theory and practice, poople have explained clearly the most of hydrological phenomenon such as rainfall, infiltration, evaporation, and simulated them by hydrological models (hydraulic and hydrological models)

Accordmgly, hydraulic and hydrological models are tools to address the real hydrological cycle in a simplified way That kind of models are used for understanding

the hydrological processes as well as making hydrological prediction if there are some

waler Tesources management and utilization activities arc implemented (Tuan 2012) The models ara applied several algorithms to provide a quantitative relation between

the input dala (eg rainfall, meteorological dala) and output (eg nmoff) The

mathematical models have been developed from 19th century with the simplest rainfall-un off model by Mulvaney (1851) to more sophisticated models suich as MIKE

Package developed by Danish Hydraulic Tnstitute; Soil and Water Assessment Tools

(SWAT), HEC model developed by Hydraulic Engineering Center- USA, SIMONA 31) hydrodynamic models by the Dept of Public Works and Delft 2D/3D by

WIIDELFT HYDRAULICS Those models are used for simulation of Now, water

quality and sediment transport in estuaries, rivers, utigation system, channels and

others hodies They are fimdamental to integrated water management as used for

planning and decision making (Twan 2012)

‘The figure below shows the relationship between the various representations of

amodel (Van Waveren et al 1999)

Trinh Xuan Mank

MSc Thesis

basis of knowledge of the system and

serves as the basis for a mathematical

programme [ nee kK model his model may be solved either

+ analytically or numerically The model

mathematical acre vealed is further refined inlo a model

medal system (Van Waveren ct al 1999)

Figure 2-1: Relationship between the

various representations of a model

Hydrological models have been used frequently in waler resources planning and management such as hydrological forecasting, reservoir operation, water quality, research on flood, inundation and drought, designing irrigation system, supporting, for

objectives, considering input data and output data, expected results and solutions

There are many studies on water field thal using model ax an effective tool to solve

problems According to Piman et al (2012), the authors used HEC and SWA'T models

lo simulate and evaluate flow changes from hydropower development and operation in

rivers: ScKong, Se San and Sepork of the Mokong basin Long ct al (2007) used MIKE

11 simulation model to set up control strategies for Lloa Binh reservoir operation ‘hey concluded that this model is an effective tool for optimizing complex system

Bahremand and Smedt (2007) used distributed hydrological modeling (WETSPA) and

sensitivity analysis in ‘lorysa Watershed, Slovakia to predict daily discharge value

They also presented that a strategy by incorporating a model-independent parameter

estimator PEST for automatic calibration and sensitivity analysis

In this study, MIKE 11 model will be selected to rout the flow, which is released

from the Cua Dat Reservoir operation to the downstream area ti order Lo evaluate or

test discharge value within constraint system at control points MIKE 11 model is a

Trinh Xuan Mank

MSc Thesis

11

strong model This model has been applicd widely in Victnam for many projects, especially in field of water resources

IL4 MIKE model

Many kind of hydraulic models have been applied widely in water resources issues MIKE 11 model is one of hydraulic models which have used popularly in

Vicinam The MIKE 11 model has been developed by DAT waler and environment

(Danish hydraulic institute) ‘This model is a professional engineering, software package for simulation of flow, water quality and sediment transport in estuaries, rivers, irrigation system, channels and others bodies (DHI 2011)

‘The study area has slope topography, short length of river and combine complex rain regime to make flood regime change complicatedly In this study, the author selects the MIKE 11 model for routing the flow on the Ma-Chu river network ‘To apply this model for study area, the understanding of model theory plays an important role The briefly description of the model theory according to DHI user's manual as

Taltowing (Kmen! 2008):

The most commonly applied Ilydro-Dynamic (ID) model is a flood maragement lool simulating the unsteady flows in branched and looped river networks and quasi two-dimensional flows in floodplains When using a fully dynamic wave description, MIKE 11 HD module solves the equations of conservation of continuity

and momentum (the ‘Saint, Venant’ equations) as bellow:

an implicit finite difference scheme developed by Abbott and Tonescu (1967) The scheme is setup to address any form of the Saint Venant equations such as: kinematic diffusive, or dynamic The water level and flow are calculated at each time

step, by solving the continuity equalion and the momentum equation using a ố-pont

Abbot scheme with the mass equation centered on h-points and the momentum

equation centered on Q-points By default, the equations are solved with 2 iterations

The firsh iteration staris from the results of the previous Lime slep and the second uses the centered values from the first iteration The number of iterations is user specified (DHT 2011)

Cross sections arc specified in both area and longitudinal location through the user interface The water level (h points) is calculated ai each cross section and at model interpolated interior points located evenly and specified by the user-entered maximum distance The flow (Q) is then calculated at points midway between neighboring h-points and at structures (DIIL 2011)

The hydraulic resistance is based on the friction slope from the empirical equation, Manning’s or Chezy, with several ways of modifying the roughness to account for variations throughout the cross-sectional area (DIII 2011)

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CHAPTER III THE STUDY AREA

IIL.1 Description of the study area

III.1.1 Location of the study area

The Ma River basin is located in the northwest region of Vietnam, on the

eastern slope of the Truong Son mountain range bordering Laos on the West The

upstream basin is located in Vietnam, the middle basin is located in Laos and the

downstream is located in Vietnam Accordingly, the Ma River basin is an international

basin and is the 4" in biggest river basins in Vietnam following The MeKong, Dong

Nai and Red river basin The whole river spreads from 22°37°30""N to 20°37°30"N

and 103°05°10""E to 106°05"10""E (IWRP 2003)

- The North borders on Da river basin, Boi river and Vac river basin,

- The West borders on the Mekong river basin;

- The South borders on Hieu and Muc river basin,

- The East borders on the East Sea

V4

Figure 3-1: Location of study in the Thanh Hoa province in Vietnam

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The total catchment arca is about 28,490 Km’, of which area in Vietnam is

17,600 Km" accounting for 62% of whole area and area in Laos is 10,800 Km’

corresponding 10 38% (TWRP 2003) The major tributaries of the Ma river system

originates from the high mountains of ‘uan Giao district which belongs to Lai Chau province, Vietnam The highest point of the upstream part is 1,500 m, the river flows

through the area of provinces and malion, namely, Son Ia, Tai Chau, Hoa Binh, Laos

and Thanh Hoa, and flows into the Hast Sea finally via three river mouths, namely Hoi, Lach Truong and Lach Sung Accordingly, Iloi river mouth is a main mouth of the Ma River, The Ma River has length of 512 Km of which 102 kin is located in Laos and in

Viet Nam is about 410 Km

Table 3-1: Distribution of natural areas according to provincial border

, weit cage [Natural : Possible ở

Na | Provincial units [27 agricultural forestry soil Geography

I Laos 1.098 751 | 32.962 824.063 High mountain

‘The Ma river flows on the Northwest Southeast direction, the river direction is

similar ta tectonic direction, the length of major river is around 512 Km, originates from the highland of Tuan Gian district, flows through some of provinces, enter into

Thanh Ifoa province at Muong Lat, Quan Iloa location to discharge the [last Sea at Hoi estuary The basin has river density of 0.66 km/km’”, the meandering index is 1,7 the

shape index is 0,17, the average slope of the basin is 17,64 (TWRP 2003)

The Chu River basin is one of main tributaries of the Ma River in this river

basin Tt is located m the downstream area The catchment of Cha River is about 7,500

kan’, of which 65% are located in Laos and 95% of Chu river catchment area is in

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15

mountains (WRP 2003) The Chu River joins the Ma River at Giang contluence which

is about at 26 kan away from Ma river mouth The river originates from Sam Nua high mountain which belongs lo Lacs, with elevation of 2,000 m, this river flows meanderingly in dangerous high mountains such as Phu Nam (2,050 m), Phụ Bo (1,455 m), entering into Viet Nam at Nghe An province The main flow has a length of 325

Km of which 100 Km is located in Vietnam

In Vietuam’s region, the Chu River flows on narrow and slope valleys with a lot

of waterfalls There are 15 waterfalls from Muong Iinh to Cua Dat location From the confluence of the Dat River to downstream, the river networks have sisen significantly, the Chu River has a protected dyke system and many large tributaries such as the Am River, the Dat River and the Dang River Among these tributaries, the Am River is a largest one

The Buoi River is a second main tributary of the Ma River This river originates from Chu Mountain which belongs to Lloa Linh Province The main river flows towards North-South direction joining the Ma River at Vinh Khang position The

length of this river is about 130 km, basin area is 1,790 km” and average slope is 1.22

The upstream of the Buoi River includes three major stream, namely Cai, Bin and Cong Toa streams

The Cau Chay River is originated from Den Mountain flowing, towards East- West direction though out delta of Ma River south and Chu River north The total

length is about 87.$ km and basin area is $51 km’*

The table 3-2 shows detailed characteristics of river shape in the Ma-Chu river

No | River Basia tre elevation |width |dope |demsity |InAatrical [` dering,

m2) t4) đam) Gn} (60) | damian’) | 2 [index inde finder index

RIVER AND METEO-HYDROLOGICAL STATION NETWORK

(OF MA-CHU RIVER BASIN IN THANH HOA PROVINCE

THANH HOA PROVINCE,

Figure 3-2: Ma— Chu River Network in Vietnam

IIL.1.3 Topographical characteristics

The Ma river basin spreads widely many regions between Vietnam and Laos This basin ranges from Truong Son Mountain range to Northern Bay, the topography is strongly fragmented and changing complexly The main slope directly ranges from West-North to East-South The topographical elevation varies from 1.0 m to 2000 m which can be divided into three main categories of topography, are described as below

- High mountain terrain: This area is in the upper part of the river basin: from Ba

Thuoc location to upstream of Ma River, and from Cua Dat location to upstream of

Chu River The highest elevation of this topography is Phu Lan Mountain with

elevation of 2,275 m The elevation changes towards North-South direction The area

of this topography is about 23,228 km? and it takes 80% in total The forestry trees are

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primary on this one Agricultural land is around 75,968 ha and accounted for 3,26% of

natural area, the current area for agriculture is 51,466 ha There are many river valleys,

those are advanced to construct multi-purpose- reservoirs in order to supply water for

many objectives such as power generation, water supply, flood prevention and control

and water environment

- Highland terrain: This area almost distributes in the districts such as Thach Thanh,

Cam Thuy, Ngoc Lac, Trieu Son, Tho Xuan in the Thanh Hoa province and Tan Lac, Lae Son, Yen Thuy in Hoa Binh province The elevation of this terrain varies from 20

m to 150 m, This region has a potential to develop industrial plants, special trees within

cultivated area of 85,100 ha, current cultivated area is 58,100 ha On this terrain there

are many streams, rivers which have potential to construct reservoirs in order to supply water for irrigation, domestic supply, flood control and environmental improvement

- Valley terrain: This terrain lies totally in the Thanh Hoa province, and it has

elevation from + 1.0 - +20 m In this terrain, the deltas have been formed due to the development of river network such as Vinh Loc, South of Ma River — North of Chu River, South of Len River

11.1.4 Geological, land and vegetable characteristics

A- Geological and land characteristics

This river basin has some geological ard soil charactaristes as following

- ‘The upstream of the Ma River, the Chu River and Buoi River are mainly Magma-

sediment Sand and gravel concentrate along the rivers

- The middle of the Ma river basin: matertal construction is abundant

- The downstream has been generated by Preterozoi Nam Co stratum and Paleozoi formation developed strongly in Thanh Iloa province where Merozoi sediment is major

- ‘The Ma River Basin has 40/60 types of soils and has formed into lIsoil groups

Sandy soil; Salt soil: Acidic alum soil, Alhrvial soil, Bog soil and Permatrast soil; Grey

soil; Black soil; Red soil; Humus soil, Valley soil; Leachy soil

- Thanh [oa province has 8 types including: Sandy soil; Salt soil; Alluvial soil; Grey

bog soil, Black soil, Grey soil, Red soil and Leachy soit

- Among 8 soil types in Thanh Hoa provinee, Alluvial soit is main soil in della and important soil to form a sustainable agriculture in local region

B- Vegetable cover characteristics

Vegetable surface on the basin is very abundant in types, categories and is formed by differentiation of climate, geography and human activities

Geography of the basin cecupics an important role in forming the vegelable on

this basin: high mountain terrain always has types of vegetation such as wide leaf forestry and brushwood Llighland terrain forms wide leaf forest, secondary

brushwood, bamboo Dela terrain 3s mainly industrial trees, rice, fruit-lrees

Among categories of vegetation, type of secondary vegetation and plantation are

major Natural vegetation still is existed, but little

TM.2 Climate and hydrological condition

11.2.1 Climate condition

The Ma river basin spreads on two lativades and longitudes Therefore, the

climate of region varies on space The region has the tropical monsoon climate There are four seasons in year including spring, summer, autumn and winter, Climate of

different regions are spatial and temporal distribution The upper area is located on

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North-West pattern climate and Chu River is on Central North pattem climate The

others are located on interaction area between above climates (IWRP 2003)

a) Precipitation

Precipitation of the Ma river basin has been divided into three different regions

The upper part of Ma River has rain regime of Northwest region, the wet season starts

early and Gnish carly than middie region The Chu River basin tics on Central North

rainy region, the wet season comes late in range of 15 20 days; finish late in range of

10-15 days than Northern region

The annual average rainfall of the region varies from 1100 to 1860 mm/ycar

‘The region has two seasons of rain which are dry season and wet season According to the statistical data of many years, the wet season of the Ma River upstream frequently begins from May to November and the dry season is from December to April the rainy season of Chu river basin begins frequently at the end of November to the

beginning of December Total annual rainfall of two seasons is strongly dispropertate

The tolat rainfall of wel season accounts 65 — 70% of total armual raindali, the total

rainfall in dry season only accounts 30-35% of total annual rainfall

Table 3-3: Average annual rainfall for many years at some stations

of the Ma river basin

Maximum rainfallin | Mininum raintall in

X (am) Year =| X(mm) Year

Song Ma 1964 2010 1,134 1,512 1973 906 1984

Sop Cop 1963- 2010 1172 1,656 1970 806 1969

Tien Kiet 1962- 2010 1/877 2,444 1963 1,06 1986

1iet Xuan I1960- 2010 1,856 2,680 1973 1,229 1976

1a Thuac II959- 2010 1,713 2,884 1963 693 1977

Cam Thuy 1960- 2050 1,712 2,674 1963 1,E31 1987

Yen Dinh II962- 2010 1,500 2,269 1980 $31 1977

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MSc Thesis

Maximum rainfall in | Minimum rainfall in

(Source: Final engineering report af Cua Dat Reservair in operation period -20\A)

Table 3-4: Annual rainfall characteristics

Winer has North — FasL monsoon wind duc to strony Norther circulation,

average wind speed is 2-3 m/s The North-Last monsoon wind commonly begins from

December to February of next year In summer the common wind direction is South- ast wind due to the Northern Air Circulation and the low position of Gulf of Tonkin,

it brings much more moisture to make heavy rain The average wind speed is from 2 —

2.5 m/s This wid occurs from March lo Oclober with armual year Besides thal, there

is dry and hot South- West wind in April and May It only occurs 3-4 times in year with 4-5 days for one

Table 3-5: Monthly and annual wind speed at some stations

of the Ma river basin (m/s)

MSc Thesis

There are 02 regions on the Ma river basin with different, lermperature regime

‘The highland, cold season starts from November to February, dry season is from March

to October The temperature of this region is similar to North- West region The delta

of Ma river, average annual temperature is higher than the highland The Winter ends

early than North region form 15 — 20 days, the highest temperature is higher than

highland On whole basin, average annual temperature changes from 22°4 to 23.6°C

Avemge sunshine hours are range from 1,756.7 1o1 896.4 hra/year

‘Table 3-6; Average monthly temperature for many years at some stations

‘Total yearly evaporation on the basin is from 872 mm to 925 mm Minimum

daily average is about 1.3 mm/day, maximam is 46 mm/day The maximum

evaporation happens in May, June and July ‘The difference of land evaporation and

water evaporation AZ = 230 — 250 mm/year

Table 3-7; Monthly average evaperation of some stations of the Ma River Basin

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MSc Thesis

Tinh Gia [46,3] 36.5 | 40.2 53.9 |106.3|124.8|138.5 | 88.2 | 68.0 78.5| 76.1 | 68.1 | 925.4 Tuan Giao |63.9| 50.6 | 49.7 55.2 | 86.5 | 88.3 |101.6| 68.1 | 63.0 2?4.4| 78.3 | 76.7 | 856.3

months which have maximum flow is July, August and September with 53 56 % in

total while that of August has maximum flow with 20 — 30% in total On the Chu

River, Hood season often occurs from July to October, accounts Lor $2 — 60% in total,

‘the month that has maximum flow is September with 20 -24 % in total anmual flow

Dry flow occurs in dry season in year The Ma River Basin has dry season which is from November to May Bosides that dry scason spreads 08 months, from

October to June on the Chu River Basin Amount of flow in this season only takes 20

35% in total In general, dry season can be divided into 03 periods: First period

includes 02 months (November aud December), this period can be seen as middle

period between 02 seasons, maximum middle dry period is from January to April in

year

THL.3 Population and economic characteristics

10.3.1 Population of the study area

According 1o the statistical yearbook 2012, the population of the Thanh Hoa

TL3.2 Economic characteristics

Based on statistical data in year of 2007, gencral economic distribution of the Thanh Lloa province was as follow: Industry was 36.87 %, Service was 34.77 %, Agriculture, Forestry and Fishier was 28.36 % of GDP in year of 2007 was 25,689.3 billion VND Ihe economic growth rate was about 10.5 %

The major economic activities were paddy rice cultivation, farming of industrial crops, trading, livestock breeding and handicraft

TIL4 Description of the Cua Dat Reservair

- Position

The Cua Dal reservoir has been constructed on Chu River aud in Xuan My Commune, Thuong, Xuan District, Thanh Hea provinee (Figure 3-4) This is the largest reservoir which has maximum storage on the Ma — Chu river system with total storage

of 1,364 million cubie meter Some main parameters of the Cua Dat Resorveir are

shown in the table 3-8

-Main abjectives of the reservoir:

This is a multi-purpose reservoir wilh following objcclives:

- To control flood in order te protect downstream area with probability flood of 0.6 % To ensure water level of the Chu River at Xuan Khanh station (Tho Xuan district) is lower than 13.71 meter;

- Supplying domestic and industrial water with suitable discharge of 7.715 m°/s,

- Inrigating for 86,862 ha of cultivated land (Including Nam Song Chu region is 54,301 ha and Bae Sang Chu—Nam Song Ma is 32,831 ha)

- Generating hydropower with installed capacity of 97 MW

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- Supplying additional water in dry scason with discharge of 30.42 m’¥s in order

to control salt intrusion at Ham Rong Bridge (lower than 1 %o)

Table 3-8: Some main parameters of the Cua Dat Reservoir

1 Basin parameters

m Reservoir parameters

1 Surface area of the reservoir at useful water level kmẺ

TH Construction

Dam

Valve

1 Surface weir with arc valve

Hydropower Plant

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MSc Thesis

Figure 3-4: The location of the Cua Dat Reservoir on the Ma-Chu river system

- Existing operation rule curve of the Cua Dat Reservoir:

Reservoir operation plays an important role and is one of problems related to

water resources planning and management Generally, after dam construction, an operation policy has been established to help managers giving significant decisions Operation policy is determined based on water storage, water demand and all of

information of inflow with current reservoir status, The single purpose reservoir

decides an operation policy which aimed to maximize that purpose interest The multi-

purpose reservoir is optimal release allocation in order to balance interest among purposes Finally, the complex operation is based on amount of objectives and membership functions

The Cua Dat Reservoir has been operated since 2012 Annual operation policy

of this reservoir is established by Ministry of Agriculture and Rural Development (MARD) According to new operation policy during the flood season in 2013 to the

beginning of flood season in 2014, included 7 main chapters with following concepts

(1) General article; (2) Regulated operation in flood season in 2013; (3) Regulated

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operation in dry scason in 2014, (4) Emergency operation, (5) Monitoring Meteorological — hydrological data; (6) Responsibility and Right, (7) Implementation policy According to Ihe purpose of this thesis, the third policy is considered to be the most important The articles of third poticy will be briefly described as below

Article 9: Before the dry season in 2014, Song Chu Irrigation Company has to plan to supply water which is based on current storage reservoir, meleo-hydrological forceast, water demand It should be reported to the Department of Agriculture and Rural Development of Thanh Iloa province, and all of water users in the system

Article 10 Regulate watcr level of reservoir in dry scason

1- During regulated operation, the reservoir elevation must be above or equal the lower rule curve in operation policy

2- Lowest reservoir elevation at the end of every month is described as below:

Article 17) When the reservoir clevation is above or equal the lowesL rule curve, Song

Chu Inigation Company oust supply cnough water to all of walor users according Wo

the water supply planning

Article 12: Hydropower genvralion schedule of the Cua Dat and Doc Cay hydropower

plant have to follow the inigation schedule of the Cua Dat rescrvoir

Article 13° Operate waler supply in some cmergency casos

1- When the reservoir elevation is lower than lower rule curve and above mactive

level, Song Chu Irrigation Company and water uscrs nced to implement water saving solutions

2- When the rescivoir clevation is equal or lower than inactive level, Song Chu

Ligation Company need to plan a water supply schedule using inactive storage, then, reports the Department of Agriculture and Rural Development, Thanh Iloa province in order to make decision and implement

Some figures that the author collected after the field survey to the Cua Dat

Reservoir in 2014 Those pictures present clearly constructions or parameters related to the Cua Dat Reservoir such as dam, flood valve, spillway, storage, intake tower, and

weir Those pictures are as below:

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CHAPTERIV DATA AND METHODOLOGY

IV.A Data collection

In this thesis, the author used some kinds of data for the contents such as Determining water demand, Optimizing reservoir operation and Numerical model The datascts were used in this study including meteorological data, hydrological data, the Cua Dat Reservoir data and some other information regarding to crops, population and industrial zones They are listed in the following table

‘Table 4-1: Kinds of data were used in the study

- Rainfall National center for Hydro-

- Evaporation Meteorclogical Service

- Wind speed

= Sunshine hours

> Water level of rivers National center far Hydro-

Hydrology - Discharge of rivers Meteorological Service

- Crops on cullivated area

- Industrial zone

The above data set were accumulated from Vietnamese Institutions and Organivations such as the National center for Melzo-hydrologival Service and Song Chu Lrigation Company (Table 4-1) The kinds of data have been established as well

as checking, approved by these organizers Hence it is able to have confidence into those sources The dala collection plays an important role in the thesis calculation, as a foundation 1s to determine water demand of each crop, operate the reservoir and set the

hydraulic model for study area and achieve the better output of this thesis so far

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MSc Thesis

In the study area, there are many rainfall stations and meteorological stations

These stations have been located in or close to the basin and have a long time period of

observation (from 1980 to 2009) However, the author did not use all of them, it only

used some of them due to data quality and location of stations

In order to define the water demand of each crop and cultivated plants, the

author used the meteorological data of the Thanh Hoa station such as rainfall,

evaporation, relative humidity, wind speed and sunshine hours within time interval of

daily period of 02 years (2011 and 2012) Some of figures of these data are shown as

following

According to the Figure 4-1, we can see that maximum rainfall occurs in the

month of September in year of 2011 and 2012 The rainfall in the month of January to

May is quite small The rainfall increased significantly from June to September and it

reaches a peak at September with more than 700 mm in year of 2011, more than 400 in year of 2012 Then, it decreased from October to April

Monthly rainfall at Thanh Hoa station in year of 2011&2012

800

1 201