WATER BALANCE FOR MA RIVER BASIN IN THE CONTEXT OF CLIMATE CHANGE
MSc Thesis

ABSTRACT
Water is one of the most common and most important substances on the earth's
surface. It is essential for the existence of life, and the kinds and amounts of vegetation
occurring on various parts of the earth's surface depend more on the quantity of water
available than on any other single environmental factor (Kramer, Paul J.; Boyer,
1995). Facing with water crisis has singled out as a major worldwide concern. Under
the main impact of Climate change, it is considered as an added driver for many of the
societal and environmental problems of the 21st century. Climate change may affect
water systems through increased/unusual spatio-temporal variability, long-term
temperature and water balance changes, and sea-level rise which in turn have
implications for water security, food security, energy security, health of human and
ecosystems, and human livelihoods (Vörösmarty et al. 2000; Richardson et al. 2011).
Water availability will be increasingly affected by climate change, which in Africa
could expose 250 million people to greatered water stress. In some countries drought
could halve the yields from rain-fed agriculture by 2030s. Across Sub- Saharan Africa
and South and East Asia drought and rainfall variations could lead to large
productivity losses in cultivated food staples (Development, 2015). By the contrast of
the decrease of water availability and the increase of water demand gather with the
conflict between different interests of stakeholders become a huge water management
task.
The Ma River basin is one of the largest rivers in central Viet Nam, orginated from the
southern of Dien Bien province, flowing through the Ma river district of Son La
province, through Laos and into Vietnam by Ba Thuoc district, Thanh Hoa province.
Ma river basin has abundant water resources. However, the demand for water is rising
day by day under the pressure of population and development - social growth.
Moreover, the uneven distribution of water resources in time and space with the
requirements of environmental flows, leading to water shortages appear. Besides, the
competing interest of different stakeholders even exaggerates the issue. Moreover,

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WATER BALANCE FOR MA RIVER BASIN IN THE CONTEXT OF CLIMATE CHANGE
MSc Thesis

impact of climate change on temperature and annual rainfall also has to concern as its
negative influence to water supply capacity.
The objectives of research are to analyze the water balance in the basin in three
scernarios: baseline (2002-2012), future scenarios with socio-economic development
text into account impacts of climate change (RCP4.5 and RCP8.5) in 2030s. The water
use activities in this basin such as irrigation, industry, domestic… are also taken into
account. In order to get these objectives, WEAP model is implemented to simulate the
water balance in the basin. MIKE-NAM model is used to simulate the inflow to
ungauged basins. CROPWAT model is applied to estimate the water requirement for
crop.
The results shows that the imbalances between water supply and water demand occur
in the dry season. In 2030s, the system cannot supply sufficient water quantity for the
projected growing demand of socio-economic development scenario. The unmet
demand is going up compared to the current scenario. However, the situation is much
more severe in the scenario in which the climate change impacts are considered.

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MSc Thesis

DECLARATION
I hereby certify that the work which is being presented in this thesis entitled, “Water
balance for Ma river basin in context of climate change” in partial fulfillment of the
requirement for the award of the Master of Science in Integrated Water Resource
Management, is an authentic record of my own work carried out under supervision of
Dr. Ngo Le An and Associate Professor. Nguyen Thu Hien.
The matter embodied in this thesis has not been submitted by me for the award of any
other degree or diploma.
Date:

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ACKNOWLEDGMENT
I would like to express my deepest gratitude and sincere appreciation to my advisor,
Doctor Ngo Le An, who is the Deputy Head of ThuyLoi University’s Hydrology and
Water Resources Division and my co-advisor, Associate Professor Nguyen Thu Hien,
Dean of Thuyloi University’s Water Resources Engineering Faculty for their patient,
valuable advice and continuous encouragement throughout the process of this thesis
work.
I would especially like to thank my colleagues in the National Centre of Water
Resource Planning and Investigation (NAWAPI), where I am working for supporting

me in many ways during the time I am busy with my thesis.
I would also like to acknowledgement my friends from Thuyloi University including
Ms. Vu Thi Thu Phuong, Mr. Syphachan Phommachan and many others for their help
to prepare input for models.
Finally, I must express my very profound gratitude to my parents and to my husband
for providing me with unwavering support and continuous encouragement throughout
my years of study and through the process of researching and writing this thesis. This
accomplishment would not have been possible without them. Thank you.

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TABLE OF CONTENTS
ABSTRACT .................................................................................................................... i
DECLARATION .......................................................................................................... iii
ACKNOWLEDGMENT .............................................................................................. iv
LIST OF FIGURES ..................................................................................................... vii
LIST OF TABLE .......................................................................................................... ix
CHAPTER 1: INTRODUCTION ................................................................................ 1
1.1. Background............................................................................................................................... 1
1.2. Problem statement.................................................................................................................... 1
1.3. Research Objectives................................................................................................................. 2
1.4. Research questions ................................................................................................................... 3
1.5. Methodology ............................................................................................................................ 3
1.6. Structure of the thesis............................................................................................................... 3

CHAPTER 2: LITERATURE REVIEW ................................................................... 5
2.1. Water balance ........................................................................................................................... 5
2.2. Climate change impact on water resources ........................................................................... 6
2.3. Climate change scenarios ........................................................................................................ 8
2.4. Models for Integrated Water Resource Management (IWRM) ........................................ 10
2.4.1. Water Balance Modeling - WEAP ...................................................................... 10
2.4.2. Rainfall – runoff Modelling: MIKE 11- NAM ................................................... 11
2.4.3. CROPWAT 8.0 .................................................................................................... 13
CHAPTER 3: DESCRIPTION OF STUDY SITE .................................................. 15
3.1. Geographical location and topography ................................................................................ 15
3.1.1. Geographical location .......................................................................................... 15
3.1.2. Topography.......................................................................................................... 16
3.2. Climate .................................................................................................................................... 17
3.3. Population - economic and social conditions ...................................................................... 20
3.3.1. Local Administration ........................................................................................... 20
3.3.2. Population ............................................................................................................ 20
3.3.3. Economic and social conditions .......................................................................... 20

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3.4. Hydrology ............................................................................................................................... 23
3.4.1. Main River network .............................................................................................23
3.4.2. Stream network ....................................................................................................25
3.4.3. Hydraulic structures .............................................................................................25

3.5. Climate change scenarios for the study areas .........................................................25
3.6 Scenarios for water balance ................................................................................................... 28
CHAPTER 4: WATER BALANCE SIMULATION FOR MA RIVER BASIN ...31
4.1. Schematization of the Ma River Basin ................................................................................ 31
4.2. Input data ................................................................................................................................ 32
4.2.1. Runoff...................................................................................................................32
4.2.2 Water demand........................................................................................................42
4.3. Water balance for current scenario in the basin .................................................................. 54
4.4. Water balance calculations for climate change scenarios in the period 2020-2039
(2030s) ............................................................................................................................................ 57
CHAPTER 5: CONCLUSION AND RECOMMENDATION ................................66
5.1. Conclusion .............................................................................................................................. 66
5.2. Recommendation ................................................................................................................... 67
REFERENCES .............................................................................................................70
APPENDICES ..............................................................................................................72

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LIST OF FIGURES
FIGURE 1.1: THE MA RIVER BASIN ........................................................................1
FIGURE 2.1: RADIATIVE FORCING OF THE REPRESENTATIVE
CONCENTRATION PATHWAYS. ...............................................................................9
FIGURE 2.2: THE SCHEMATIZATION OF THE MA RIVER BASIN ...................11
FIGURE 2.3. PROCESSES OF NAM MODEL ..........................................................13

FIGURE 3.1: THE MA RIVER BASIN .....................................................................16
FIGURE 3.2.: EXAMPLES OF HADGEM2-AO MODEL’S OUTPUT IN ASIA ....26
FIGURE 3.3: GRID OF HADGEM2-AO MODEL (RED DASH-LINE) WITH RAIN
GAUGE STATIONS IN THE MA RIVER ..................................................................26
FIGURE 3.4: RESCALING FACTORS BETWEEN AVERAGE MONTHLY
RAINFALL IN THE FUTURE PERIOD AND HISTORICAL PERIOD FOR RCP4.5
.......................................................................................................................................27
FIGURE 3.5: RESCALING FACTORS BETWEEN AVERAGE MONTHLY
RAINFALL IN THE FUTURE PERIOD AND HISTORICAL PERIOD FOR RCP8.5
.......................................................................................................................................28
FIGURE 3.6: THE OPERATION CURVE OF TRUNG SON RESERVOIR ............29
FIGURE 4.1: SCHEMATIZATION OF THE MA RIVER NETWORK....................32
FIGURE 4.2: FOUR SUB-BASINS IN THE MA RIVER BASIN .............................33
FIGURE 4.3: OBSERVED AND SIMULATED HYDROGRAPH IN
CALIBRATION PERIOD (1966-1971) (M3/S) ...........................................................36
FIGURE 4.4: OBSERVED AND SIMULATED HYDROGRAPH IN VALIDATION
PERIOD (1973-1981) (M3/S) .......................................................................................36
FIGURE 4.5: OBSERVED AND SIMULATED HYDROGRAPH IN SIMULATION
PERIOD (2002-2012) (M3/S) ........................................................................................39
FIGURE 4.6: OBSERVED AND SIMULATED HYDROGRAPH IN
CALIBRATION PERIOD (1962-1966) (M3/S)............................................................40
FIGURE 4.7: OBSERVED AND SIMULATED HYDROGRAPH IN VALIDATION
PERIOD (1967-1968) (M3/S) ........................................................................................40
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FIGURE 4.8: MONTHLY INFLOW TO THE BASIN IN THE PERIOD 2002-2012
(106 M3) ......................................................................................................................... 42
FIGURE 4.9: METEOROLOGICAL DATA IN CROPWAT .................................... 45
FIGURE 4.10: RAINFALL DATA IN CROPWAT ................................................... 45
FIGURE 4.11: CROP DATA IN CROPWAT ............................................................. 46
FIGURE 4.12: SOIL DATA IN CROPWAT .............................................................. 46
FIGURE 4.13: THE IRRIGATION REQUIREMENT FOR EACH AREA (L/S/H) . 47
FIGURE 4.14. THE FREQUENCY CURVE OF THE DRIEST MONTHLY FLOW
IN CAM THUY STATION (M3/S) .............................................................................. 51
FIGURE 4.15: WATER REQUIREMENT BY SECTORS IN THE PERIOD 20022012, CURRENT SCENARIO (106 M3) ....................................................................... 55
FIGURE 4.16: UNMET DEMAND BY MONTHS IN THE PERIOD 2002-2012,
CURRENT SCENARIO (103 M3) ................................................................................ 56
FIGURE 4.17: .MONTHLY INFLOWS TO THE AREAS IN KB4.5 SCENARIO .. 59
FIGURE 4.18: MONTHLY INFLOWS TO THE AREAS IN KB8.5 SCENARIO ... 59
FIGURE 4.19: COMPARISON OF MONTHLY INFLOWS BETWEEN PAST
SCENARIO(BASELINE), KB4.5 AND KB8.5 SCENARIOS. ................................... 60
FIGURE 4.20: UNMET DEMAND BY MONTHS IN THE PERIOD 2020-2039,
KB4.5 SCENARIO (106 M3/S) ..................................................................................... 61
FIGURE 4.21: TURBINE DISCHARGE AND HYDROPOWER GENERATION OF
TRUNG SON RESERVOIR, KB4.5 SCENARIO. ...................................................... 62
FIGURE 4.22: UNMET DEMAND BY MONTHS IN THE PERIOD 2020-2039,
KB8.5 SCENARIO (106 M3/S) ..................................................................................... 63
FIGURE 4.23: TURBINE DISCHARGE AND HYDROPOWER GENERATION OF
TRUNG SON RESERVOIR, KB8.5 SCENARIO. ...................................................... 64

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LIST OF TABLE
TABLE 2.1: DESCRIPTION OF EACH REPRESENTATIVE CONCENTRATION
PATHWAYS (RCPS) (IPCC, 2014) ............................................................................. 10
TABLE 3.1: MONTHLY AVERAGE TEMPERATURE IN THE MA RIVER BASIN 18
TABLE 3.2: MONTHLY AVERAGE HUMIDITY IN THE MA RIVER BASIN .... 18
TABLE 3.3: ANNUAL AVERAGE RAINFALL IN THE MA RIVER BASIN ........ 19
TABLE 3.4: THE ELEVATION –AREA - STORAGE RELATIONSHIP OF TRUNG
SON RESERVOIR ........................................................................................................ 30
TABLE 4.1: DESCRIPTION OF SUB-BASINS ......................................................... 34
TABLE 4.2: NAM PARAMETER EXPLANATION AND BOUNDARIES
(SHAMSUDIN & HASHIM, 2002) .............................................................................. 34
TABLE 4.3: THE RELIABILITY OF NASH COEFFICIENT ................................... 35
TABLE 4.4: PARAMETERS FOR SUB-BASIN 1 ..................................................... 37
TABLE 4.5: FLOWS INSIDE OF SUB-BASIN 2 ...................................................... 37
TABLE 4.6: PARAMETERS FOR SUB-BASIN 3 ..................................................... 38
TABLE 4.7: FLOWS INSIDE OF SUB-BASIN 3 ...................................................... 39
TABLE 4.8: PARAMETERS FOR SUB-BASIN 4 ..................................................... 41
TABLE 4.9: FLOWS INSIDE OF SUB-BASIN 4 ...................................................... 41
TABLE 4.10: IRRIGATION AREAS OF THE MA RIVER BASIN IN THANH
HOA............................................................................................................................... 43
TABLE 4.11: LAND AREA OF RICE CULTIVATION IN EACH AREA. .............. 44
TABLE 4.12: VIETNAMESE STANDARD FOR LIVESTOCK CONSUMPTION . 48
TABLE 4.13: THE QUANTITY OF LIVESTOCK IN THE REGION ...................... 48
TABLE 4.14: VIETNAMESE STANDARD FOR DOMESTIC WATER USE ......... 49
TABLE 4.15: POPULATION OF EACH AREA IN THANH HOA PROVINCE ..... 49
TABLE 4.16: INDUSTRIAL PRODUCTION BY REGION IN CURRENT ............. 50

TABLE 4.17: WATER SURFACE AREA FOR AQUACULTURE IN THE BASIN. 50
TABLE 4.18: POPULATION IN EACH AREA OF MA RIVER BASIN IN 2030S . 52
TABLE 4.19: INDUSTRIAL PRODUCTION BY REGION IN 2030S ..................... 53
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TABLE 4.20: LAND AREA OF RICE CULTIVATION IN EACH AREA IN 2030S53
TABLE 4.21. WATER SURFACE AREA FOR AQUACULTURE IN THE BASIN
IN 2030S........................................................................................................................ 54
TABLE 4.22: MONTHLY FLOWS INSIDE OF EACH SUB-BASIN IN THE
PERIOD 2020-2039 FOR KB4.5 .................................................................................. 58
TABLE 4.23: MONTHLY FLOWS INSIDE OF EACH SUB-BASIN IN THE
PERIOD 2020-2039 FOR KB8.5 .................................................................................. 58

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CHAPTER 1: INTRODUCTION
1.1. Background


Figure 1.1: The Ma River basin
The Ma river basin is located in the eastern of Truong Son, West North northern and
Central Laos. The basin is located in the geographic location from 19037’30” to
22037’33”north latitude and from 103005’10” to 106005’10’’ east longitude. Ma river
originates from the southern slopes Pu Huoi Long range in Tuan Giao Dien Bien
province, and runs from the northwest - southeast through Son La, Sam Nua (Laos),
Hoa Binh, Thanh Hoa and then flows into the sea at 3 inlets: Lach Sung, Lach Truong
and Cua Hoi. North of the Ma River basin borders Da River and Boi River basin; West
of the Ma River basin borders Mekong River basin, Sourth borders Hieu River and
Yen River, East borders East Coast.
1.2. Problem statement
The Ma river basin has complex geological structure with many rock formations very
abundant lithological composition and influenced strongly by tectonic activity two
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regions contain of Northwest and Truong Son, Ma River basin has formed many
regions have different natural conditions, from the Northwest (Lai Chau, Son La.
Peace) to coastal North Central region (Thanh Hoa, Nghe An). Besides, it plays an
important role in economic development & social, ecological environmental protection
of Thanh Hoa province in particular and the North Central region in general.
Although Ma river basin has much potential for development of economic, it is
difficult to promote the potential of natural resources, especially financial water
resources. Moreover, basin always appear natural catastrophes related to flows like
floods, flash floods, drought... to hinder the process of economic and social

development there. Also, in recent years in the dry season in some parts of the Ma
River basin appear salinity intrusion significant impact to production operations and
activities of the people in the region. Climate change is also the “hot” issue in the
water resources problems. The climatic impact on the water regime may also
exacerbate other environmental and social effects of water management. For instance,
the decrease runoff can cause pollutants or exacerbate the spread of water-borne
disease. Climate change will greatly complicate the design, operation, and
management of water-use systems (Gleick & Shiklomanov 1989). On the other hand,
climate change that increases overall water availability could either be beneficial or
could increase the risk of flooding. Regions with an arid and semi-arid climate could
be sensitive to even insignificant changes in climatic characteristics (Linz et al. 1990)
Moreover, using of water resources still appears conflicts between water demand and
water availability. Water demand is increasing rapidly during amount of available
water decline. In order to stabilize the lives of the people, ensuring sustainable
development in the basin, finding solutions to operators, rational use of water
resources of the Ma River basin has become urgent practical needs to ensure a balance
between supply and demand.
1.3. Research Objectives
- Possibility of water supply and current situation of using water in Ma River basin.

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- Establishment of water balance model on basin and assess the level of water shortage
between supply and demand for water.

- Proposed management measures.
1.4. Research questions
Some questions are given to answer in order to get the objectives.
1. What is the water status in each region of Ma River Basin currently?
2. What are suitable tools to assess water availability and water demand in the river
basin?
1.5. Methodology
In this study, relevant data and information in the study area must be collected. The
data collection contain of: (1) time series of hydro-meteorological data; (2) water
demand of all water use activities in each region (if lack of data, must be calculated);
(3) Characteristics of infrastructures in the basin such as reservoir (4) Topography,
landuse, soiltype maps... Rainfall-runoff model is used to simulate the runoff for
ungauged basin. Then, water balance model is employed to estimate the water balance
in the basin in different scenarios (including Climate change scenarios). Finally, base
on the result of modelling, some analysis and recommendations will be proposed.
Due to the lack information of water requirement in Dien Bien province and in Laos
territory, the research only focus in the Ma river basin in Thanh Hoa province.
1.6. Structure of the thesis
This thesis is present in five main chapters including the introduction, literature
review, the description of study area, the simulation of water balance in Ma River
Basin and the result analysis, and last chapter is the conclusions and recommendations.
Chapter 1: Introduction, this chapter provides about the overview of physical
characteristic of Ma river Basin as well as brings out the problem statement about

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MSc Thesis

water resources management in the basin. In addition, a set of research questions and
the methodology are also given.
Chapter 2: Literature review shows an overview of “water balance”, “climate change
impacts on water resources.”
Chapter 3: The chapter presents overview of area which contain of characteristic of
Ma River Basin with regard to Geographical location and topography, the climate
conditions, the socio-economic development, the illustration of river network, the
current water use activities, and the water storage.
Chapter 4: In this chapter, the simulation of models in Ma River Basin is showed. The
schematic basin is brought out; the data requirements for applying the WEAP model
are focused and demonstrated. Moreover, this chapter also defines main scenarios.
After calculating, the results of the main scenarios with respect to the water supply and
water requirement will be brought out and analyzed in this chapter. It illustrates and
compares the water shortage in needs of each water user node corresponding to each
scenario.
Chapter 5: The chapter focuses on the main findings and recommendations for the
future planning.

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CHAPTER 2: LITERATURE REVIEW
2.1. Water balance

In every business, there are some types of accounting procedure. In fact, it is essential
for a good business, not an option. For water, we also need a good accounting of water
supplies, changes in storage, and water destinations for proper management of the
resource. For irrigation engineers, proper irrigation scheduling – both timing and
amount, control of runoff, minimizing deep percolation, and the uniform application of
water – are of primary concern. In field level, water requirements of the plants are met
by the storage of soil, supplies from irrigation and rainfall, and to some extent, from
shallow groundwater tables. Losses of water from the field include surface runoff from
the field, deep percolation out of the root region, transpiration by plants, and
evaporation from the soil surface.
Field water supply has been a major focus of agricultural research and management.
The soil-water balance is a widely used method of tracking soil water supply in a field.
Water balances are essential for making wise decisions regarding water conservation,
water management, and irrigation scheduling. Water conservation implies that within
the boundaries of interest, the available water is to be conserved. Accurate
computation of water balance can help to avoid past errors and improve for the future.
The components of water balance change over time, from day to day, from year to
year, etc.
According to Ali, the field water balance is an account of all quantities of water added
to, subtracted from, and stored within a given volume of soil during a given period of
time in a given field. The water balance is merely a detailed statement of the law of
conservation of matter, which states simply that matter can neither be created nor
destroyed but can only be changed from one state or location to another. It is a mass
balance of the flow and storage of water in surface soil (for a particular depth) per unit
area basis, using the hydrologic equation:

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Inflow - Outflow = Change in storage (Ali, 2010)
Water balance calculation requires two types of boundaries: (i) physical or spatial
boundary, and (ii) temporal (time) boundary. Water balance can be studied for a field,
farm, irrigation district, or a hydrological basin. The principle is the same for all units,
but one must specify which boundary is being talked about when making
computations. Similarly, a time boundary should also be specified. (Ali, 2010)
Besides, follow different aspect from Zhang, Water balance is based on the law of
conservation of mass: any change in the water content of a given soil volume during a
specified period must equal the difference between the amount of water added to the
soil volume and the amount of water withdrawn from it. In other words, the water
content of the soil volume will increase when additional water from outside is added
by infiltration or capillary rise, and decrease when water is withdrawn by
evapotranspiration or deep drainage. The control soil volume for which the water
balance is computed is often determined arbitrarily. (Zhang et al, 2002)
Summary, a water balance equation can be used to describe the flow of water in and
out of a system. A system can be one of several hydrological domains, such as a
column of soil or a drainage basin. Water balance can also refer to the ways in which
an organism maintains water in dry or hot conditions. It is often discussed in reference
to plants or arthropods, which have a variety of water retention mechanisms, including
a lipid waxy coating that has limited permeability.
2.2. Climate change impact on water resources
In recent years, and particularly since the outcome of the second and third assessment
reports of the Intergovernmental Panel on Climate Change (IPCC, 1996) and (IPCC,
2001), it has become clear that global climate change is a scientific reality. An
increasing awareness that global climate change will affect water resources has also
clearly emerged and this has been reflected in a rapidly growing body of scientific

literature.

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Actually, water resources are arguably the most important domain to be considered in
a climate change impact assessment study. This importance stems from the fact that
climate change has direct impacts on the availability, timing and variability of the
water supply and demand, and is also related to the significant consequences of these
impacts on many sectors of our society. Water is used for human consumption,
industrial purposes, irrigation, power production, navigation, recreation and waste
disposal, as well as for the maintenance of healthy aquatic ecosystems. Its availability
and the occurrence of extreme events like floods and droughts condition the location
of urban, industrial and agriculture areas, power generation plants and trading centers.
The IPCC Third Assessment Report (IPCC, 2001) estimates a global increase of mean
annual temperature of 0.8°C to 2.6°C by 2050 and 1.4°C to 5.8°C by 2100. The study
also reports results that indicate an increase in annual rainfall induced by climate
change in high and mid latitudes and most equatorial regions, as well as a general
decrease in the subtropics. Results also show that flood magnitude and frequency is
likely to increase, due to the concentration of rainfall in winter in most areas of the
globe. Simultaneously, the decrease of low flows in many regions associated with
higher temperatures constitutes a serious threat to the quality of water resources. As
regards the impacts of climate change in Europe, the IPCC studies suggest that
Southern Europe, and namely the Mediterranean region, will be particularly affected in
a negative way. This will be especially true in the Iberian Peninsula, south of river

Tagus, where a considerable increase in temperature and a reduction in rainfall and
runoff is expected by 2100.
As pointed out by Moss et al. (2010), the research community currently needs new
scenarios. First, more detailed information is needed for running the current generation
of climate models than that provided by any previous scenario sets. Second, there is an
increasing interest in scenarios that explicitly explore the impact of different climate
policies in addition to the no-climate-policy scenarios explored so far (e.g. SRES).
Such scenarios would allow evaluating the “costs” and “benefits” of long-term climate
goals. Finally, there is also an increasing interest in exploring the role of adaptation in
more detail. This requires further integration of information for scenario development
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across the different disciplines involved in climate research. The need for new
scenarios prompted the Intergovernmental Panel on Climate Change (IPCC) to request
the scientific communities to develop a new set of scenarios to facilitate future
assessment of climate change as given by report in 2007.
The IPCC also decided such scenarios would not be developed as part of the IPCC
process, leaving new scenario development to the research community. The
community subsequently designed a process of three phases (Moss et al. 2010):
1) Development of a scenario set containing emission, concentration and land-use
trajectories—referred to as “representative concentration pathways” (RCPs).
2) A parallel development phase with climate model runs and development of new
socio-economic scenarios.
3) A final integration and dissemination phase. (Vuuren et al., 2011)

2.3. Climate change scenarios
RCPs are the third generation of scenarios. The first set - IS92 - were published in
1992. In the year 2000, the second generation - SRES - were released. The latest, now
in use, are the RCPs.
Climate change scenarios are Representative Concentration Pathways (RCPs) which
have been developing and updating by IPCC since 2013 (IPCC, 2014). Four RCPs
were selected and defined by their total radioactive forcing (cumulative measure of
human emissions of GHGs from all sources expressed in Watts per square meter)
pathway and level by 2100. The RCPs were chosen to represent a broad range of
climate outcomes, based on a literature review, and are neither forecasts nor policy
recommendations.

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Figure 2.1: Radiative Forcing of the Representative Concentration Pathways.
While each single RCP is based on an internally consistent set of socioeconomic
assumptions, the four RCPs together cannot be treated as a set with consistent internal
socioeconomic logic. For example, RCP8.5 cannot be used as a no-climate-policy
socioeconomic

reference

scenario


for

the

other

RCPs

because

RCP8.5’s

socioeconomic, technology, and biophysical assumptions differ from those of the other
RCPs. Each RCP could result from different combinations of economic, technological,
demographic, policy, and institutional futures. For example, the second-to-lowest RCP
could be considered as a moderate mitigation scenario. However, it is also consistent
with a baseline scenario that assumes a global development that focuses on
technological improvements and a shift to service industries but does not aim to reduce
greenhouse gas emissions as a goal in itself (similar to the B1 scenario of the SRES
scenarios). Four RCPs used a common set of historical emissions data to initialize the
integrated assessment models. Description of each RCP at the table below:

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Table 2.1: Description of each Representative Concentration Pathways (RCPs)
(IPCC, 2014)
Type of RCPs
RCP 8.5

Description
Rising radiative forcing pathway

IA Model
MESSAGE

leading to 8.5 W/m2 in 2100.

RCP6

Stabilization without overshoot

AIM

pathway to 6 W/m2 at stabilization
after 2100

RCP4.5

Stabilization without overshoot

GCAM

pathway to 4.5 W/m2 at stabilization


(MiniCAM)

after 2100

RCP2.6

Peak in radiative forcing at ~ 3 W/m2

IMAGE

before 2100 and decline

Following the description of each scenarios, it is appeared that the RCP4.5 and
RCP8.5 are the most suitable scenarios with the socioeconomic assumptions as well as
the current conditions of Ma River Basin, therefore, this study will reveal the insight of
the balance between water availability and water demand at the present as well as in
projected future circumstances considering RCP4.5 and RCP8.5 characteristics as the
primary influence factors.
2.4. Models for Integrated Water Resource Management (IWRM)
2.4.1. Water Balance Modeling - WEAP
WEAP model is used to simulate the water balance in the basin. WEAP, developed by
the Stockholm Environment Institute (SEI), is a practical tool for water resources
planning, which incorporates both the water supply and the water demand issues in
addition to water quality and ecosystem preservation, as required by an integrated
approach to basin management (SEI 2007). The model is semi-theoretical, continuous
time, deterministic and semi-distributed. As the model is semi-theoretical, it needs
calibration and verification.
WEAP is a laboratory for examining alternative water development and management
strategies (SEI 2005). The model simulates water system operations within a river
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system with basic principles of water accounting on a user-defined time step; it
computes water mass balance for every node and link in the system for the simulation
period (SEI 2007), (Yilmaz & Harmancioglu, 2010). Simulation allows the prediction
and evaluation of “what if” scenarios and water policies such as water conservation
programs, demand projections, hydrologic changes, new infrastructure, and changes in
allocations or operations. (Hamlat, Errih, & Guidoum, 2013)
WEAP model has two primary functions (Sieber et al., 2005):


Simulating the processes of hydrology such as runoff, evapotranspiration in
order to assess the availability of water inside a basin.



Simulating activities of anthropogenic which superimposed on the natural
system to influence water resources and their allocation to enable evaluation
of the impact of water users.

Figure 2.2: The Schematization of the Ma river basin
This model need input data for running, these data will be collected by models were
used in this thesis: MIKE 11-NAM to calculate insides flow in each sub-basin and
CROPWAT model to compute water requirement for irrigation.
2.4.2. Rainfall – runoff Modelling: MIKE 11- NAM

Hydrological models are important and necessary tools for water and environmental
resources management. Demands from society on the predictive capabilities of such

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models are becoming higher and higher, leading to the need of enhancing existing
models and even of developing new theories. Existing hydrological models can be
classified into three types, namely, 1) empirical models (black-box models); 2)
conceptual models; and 3) physically based models. To address the question of how
land use change and climate change affect hydrological (e.g. floods) and
environmental (e.g. water quality) functioning, the model needs to contain an adequate
description of the dominant physical processes.
The use of simulation models should be considered as an important tool in water
resources management and related decision-making. Hydrological models are welldeveloped and a long tradition of application exists. Rainfall – Runoff modeling is the
process of transforming rainfall into catchment runoff. Almost all rainfall - runoff
models take as input data, at least, rainfall and potential evapotranspiration and
calculate as result catchment runoff. The MIKE 11 is a powerful hydrological
modeling system which can be used in water resources management. The system,
developed by DHI, was designed to simulate water flow in rivers and open channels. It
is composed by several modules namely rainfall-runoff (RR), hydrodynamic (HD),
advection-dispersion (AD) etc., which in some cases can be used in combination and
in others cases as standalone simulators (DHI 2009)
In order to simulate the process of hydrology, NAM model was chosen to apply in this
thesis. The NAM (Nedbør Affstrømnings Model) model is a deterministic, lumped

conceptual rainfall-runoff model which is originally developed by the Technical
University of Denmark Nielsen and Hansen (Nielsen, 1973). Each sub-basin is one
unit, so the parameters and variables are considered for representing average values for
the all sub-basins. The result is a time series of the runoff from the basin throughout
the period which set up in model. So, the MIKE 11 NAM model provides both peak
and base flow conditions that accounts for antecedent soil moisture conditions over the
modeled time period. The processes of NAM model is shown in Figure 2.3.

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Figure 2.3. Processes of NAM Model
Because of the limited of data and research conditions, this thesis only focus on
surface storage and snow is not appear in the research area. The thesis is only
concentrate about surface water balancing withour considering groundwater. Input
data required in this model are daily rainfall and evaporation, and then the output data
of the model is the runoff.
2.4.3. CROPWAT 8.0
CROPWAT 8.0 for Windows is a computer program for the calculation of crop water
requirements and irrigation requirements based on soil, climate and crop data. In
addition, the program allows the development of irrigation schedules for different
management conditions and the calculation of scheme water supply for varying crop
patterns. CROPWAT 8.0 can also be used to evaluate farmers’ irrigation practices and
to estimate crop performance under both rained and irrigated conditions.


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The crop water requirement is the amount of water needed for various kinds of crops
to grow optimally, and it depends mainly on the climate conditions, crop types, and the
growth stage of crop. In this method, most of the equation parameters are directly measured
or can be readily calculated from weather data. The equation can be utilized for the direct
calculation of any crop evapotranspiration (ETc).

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CHAPTER 3: DESCRIPTION OF STUDY SITE
3.1. Geographical location and topography
3.1.1. Geographical location
Ma River Basin is located in the eastern of Truong Son Mountain Range, which is
located in Central Vietnam, Central Laos and Northwest of Northern Vietnam. The
basin is located in the geographical location from 22o37'33" to 20o37'33"N, from
103o05'10 "to 106o05'10" E. The basin has the following boundaries:
- Northeastern part is the divided watershed between Da River and Ma River

- Southwestern part is adjacent to the Mekong River basin.
- Southern part is adjacent to Ca River basin.
- Eastern part is the East Coast.
Mainstream of Ma River originates from the southern slopes of Pu Huoi Long
mountain range in Tuan Giao of Dien Bien Province, and flows in the Northwest –
Southeast direction through Son La, Sam Nua (Laos), Hoa Binh, Thanh Hoa and then
flows into the sea at 3 estuaries: Sung, Lach Truong and Cua Hoi.
The Ma River system includes the mainstream of Ma River and two major tributaries
which are Chu River and Buoi River. This river system has a total length of 881 km,
the annual total average flow is 19.52 billion m3. Network of Ma River develops in the
form of tree branches, the shape factor is 0.17, drainage network density is 0.66
km/km2.
The total area of Ma River basin is 28,490 km2 and it is stretched over the territories of
Laos and Vietnam. In which, the basin area in Vietnam territory is 17,720 km2, and the
basin area in Laos territory is 10,680 km2.

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