MOI UNIVERSITY

SCHOOL OF ENGINEERING

DEPARTMENT OF CIVIL AND STRUCTURAL ENGINEERING

QUASI TWO-DIMENSIONAL RIVER FLOOD MODELLING FOR THE BUDALANGI FLOODPLAINS

MUKU OMAI LAWRENCE

MSc/PGC/03/07

Proposal submitted in partial fulfilment for the award of degree of Master of

Science in Water Engineering, Moi University, Eldoret.

AUGUST 2009

DECLARATION

STUDENTI hereby declare that this research proposal is my original work and that it has not been

submitted in any institution.

Signed: _________________ Date: __________________Muku Omai LawrenceMSc/PGC/03/07

SUPERVISORS

We have read this proposal and approved it for submission

________________ _________________Dr. J. Kibiiy DateDepartment of Civil and Structural EngineeringMoi University

_________________________________ __________________Prof. P. Willems DateDepartment of Civil EngineeringKatholieke University-Leuven, Belgium

ii

List of Abbreviations and Acronyms

1D One-dimensional

2D Two-dimensional

DEM Digital Elevation Model

GIS Geographical Information System

WETSPRO Water Engineering Time Series PROcessing tool

SOBEK Flood Model

DHI Danish Hydraulic Institute

HD Hydrodynamic

HECRAS Hydrologic Engineers Centre- River Analysis Centre

NWCPC National Water Conservation and Pipeline Corporation

nhc Northwest Hydraulic Consultants

LiDAR Light Detection And Ranging

SAR Synthetic Aperture Radar

ASTER Advanced Spaceborne Thermal Emission and Reflection Radiometer

SRTM Shuttle Radar Topography Mission

ADCP Acoustic Doppler Current Profiler Machine

MWMC Manitoba Water Management Consultants.

WMC Water Management Consultants

MWI Ministry of Water and Irrigation

iii

ABSTRACT

Flooding problem in Budalangi has been there for quite a long time. The flooding poses a major challenge to the riparian communities as well as the Kenyan Government and these calls for a solution to this problem as it hampers the development process, further increasing the vulnerability of the rural society and thereby perpetuating and increasing the incidence of poverty.

In the past years, especially from the year 2001, the ministry of water and irrigation (MWI) has been implementing flood control works aimed at taming flooding in Budalangi by the employment of structural measures but with little success (CAS consultants, 2006).

River flood modelling is one of the techniques employed in understanding and managing the flood prone zones. In many applications, river flood modelling is performed by a one-dimensional full hydrodynamic modeling system. To model the flood plains with such a system a quasi two-dimensional approach is used which is more appropriate.

The latter approach shall be used in this research, in which the flood plains shall be modeled as a network of fictitious river branches and spills/links with the rivers. The river branches represent the topographical depressions (floodplains) and the spills correspond with the river embankments.

A Digital Elevation Model (DEM) in conjunction with MIKE 11 river model and GIS system shall be used. The GIS system shall be used both as a pre-processing and post-processing tool as well.

The main objective is to develop flood maps for different return periods using MIKE 11-gis interface. In identifying the potential flood risk zones, representative hydrographs, which are derived on the basis of an extreme value analysis shall be simulated in the model for return periods in the range of 1 to 100 years and eventually flood maps for different return periods shall be created.

The model shall be calibrated using satellite flood images. The main data to be collected shall include topographical data, river flow data, lake levels and river geometry data. The expected results shall be simulated water levels and inundation flood maps based on return periods.

iv

TABLE OF CONTENTS

DECLARATION.................................................................................................................iiList of Abbreviations and Acronyms.................................................................................iiiCHAPTER ONE..................................................................................................................11.0 INTRODUCTION.........................................................................................................1

1.1 BACKGROUND TO THE STUDY..........................................................................11.2 STUDY AREA..........................................................................................................21.3 PROBLEM STATEMENT........................................................................................31.4 JUSTIFICATION OF THE RESEARCH.................................................................31.5 SCOPE OF THE RESEARCH..................................................................................31.6 OBJECTIVES OF THE RESEARCH.......................................................................4

1.6.1 Overall Objective of the Research......................................................................41.6.2 Specific Objectives of the Research...................................................................4

CHAPTER TWO.................................................................................................................52.0 LITERATURE REVIEW..............................................................................................5

2.1 INTRODUCTION.....................................................................................................52.2 ABOUT MIKE 11 MODEL......................................................................................52.2.1 Model Features.......................................................................................................62.2.2 Model Physical Details...........................................................................................62.2.3 Model Framework..................................................................................................62.3 CASE STUDIES........................................................................................................7

2.3.2 Flood Hazard Mapping for the Skeeria River at Terrace...........................................72.3.3 Dender and Demer Catchments in Belgium...............................................................72.3.4 Entella Catchment in Italy..........................................................................................82.3.5 Kushabhadra River Canal in India..............................................................................8CHAPTER THREE...........................................................................................................103.0 METHODOLOGY......................................................................................................10

3.1 INTRODUCTION...................................................................................................103.2 DATA COLLECTION............................................................................................10

3.2.1 Data Requirements............................................................................................103.2.2 Data Collection Techniques..............................................................................10

3.3 FIELD MEASUREMENTS....................................................................................113.4 USE OF A GEOGRAPHICAL INFORMATION SYSTEM (GIS)........................113.5 COMPUTER MODELLING...................................................................................11

3.5.1 Initial Visualization of the Potential Flood Zones............................................113.5.2 Extraction of Topographical Information.........................................................123.5.3 Identification of the potential Risk Zones........................................................123.5.4 Visualization of the floodplain simulation.......................................................12

REFERENCES..................................................................................................................13

v

APPENDICES...................................................................................................................15APPENDIX 2: TIME SCHEDULE...................................................................................17APPENDIX 3: SUMMARY OF COST ESTIMATES.....................................................18

vi

CHAPTER ONE

1.0 INTRODUCTION

1.1 BACKGROUND TO THE STUDY

Growing population and economic activities along the river Nzoia have caused an

increased flood risk to riparian communities living on the flood plains. Currently, one-

dimensional (1D) hydrodynamic models have been widely used in modeling flood flows.

These types of models are computationally efficient for dealing with large and complex

river channel systems and various hydraulic structures. However, when modelling

floodplain flows where the ‘one-dimensional’ assumption is in question, then the

accuracy and appropriateness of a 1D model decreases (Willems et al., 2002).

Two-dimensional hydrodynamic models can be used for floodplain modeling. The main

constraints of 2D models are the high requirements of hardware, data and computational

time. However these models are more accurate for floodplain modeling (Timbe L., 2007).

Since 1-dimensional models are accurate to simulate water level in the main river

channel, some packages are coupling 1D-2D hydrodynamic models. The 1D model is

used to simulate the water flow in the river, while the 2D model simulates the floodplain

flow when the water exceeds the dike or embankment.

Quasi two-dimensional model shall be constructed in this research. In this approach, the

flooded areas are modeled as separate 1D river branches that are connected to the main

river by means of spills or link channels. The river branches are represented as

topographical depressions while the spills represent topographical elevations such as the

dikes and embankments between the river and the floodplains.

(http://www.kuleuven.be/river.htm)

The direction of the flood branches is taken equal to the preferential flow direction. The

cross-sections perpendicular to this direction are derived from a digital elevation model

(DEM). In this way, the volumes along the flooded areas can be described accurately. By

making appropriate assumptions for the roughness coefficients along these areas, the

model is also able to describe the water surface profile along the flooded areas.

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1.2 STUDY AREA

The study area is the Budalangi floodplains, situated at the lower reaches of Nzoia River.

The Nzoia River derives its water from the Nzoia River catchment. It measures about 334

km long with a catchment area of about 12,900 km2, with a large mean annual discharge

of 777 x 106 m3/year (www.unep.org/Training/downloads/PDFs/NRBMI_small.pdf).

Budalangi flood plains are located in new Bunyala District of western province of Kenya.

The river reach of interest is approximately 20 km and the enjoining floodplain.

The floodplain physiographically, falls on the sediment plain of the river within the

altitude range of 1100 to 1350m above mean sea level. The floodplain topography is

fairly flat to very gently undulating with gradients of less than 2%. The soils type in the

floodplain is dominantly black cotton soils (vertisols) with heavy alluvial deposition

within the river channel. Pockets of shallow murram soils (course textured) are also

evident (NWCPC, 2008).

Figure 1.1: Study Area

2

BUDALANGI

L. Victoria

FUNYULA

URANGA

UKWALA

USIGU

4 0 4 8 Miles

Ext.shpExtension.shp

L.shpL. Victoria

Studya.shpStudy Area

N

Study Area

1.3 PROBLEM STATEMENT

The problem of floods in Budalangi floodplains has been there for the last couple of

years. This has received a lot of attention both in the print and electronic media locally

and internationally.

During the short and long rains, Budalangi experiences excessive flooding waters from

the catchment areas. Hence a low safety level in the Budalangi flood plains to the riparian

communities. This is due to the high recurrence of the floods in the flood plains. River

Nzoia have created prized farmland in the floodplains, but also flood fields and the

community settlements built alongside them. Flood impacts within the Budalangi

floodplains are manifold, among them are: loss of life, health and developmental impact,

economic loss and environmental impacts (NWCPC, 2008).

Despite the concerted efforts by the ministry of water and irrigation (MWI) to tame the

floods by the rehabilitation and raising of the dyke embankments, the solution has been

elusive. This calls for a new way of solving the problem.

This research intends to investigate the possibility of increasing the safety levels via

hydraulic modelling using MIKE 11 river model.

1.4 JUSTIFICATION OF THE RESEARCH

The river flood modelling using the quasi two-dimensional hydrodynamic modelling is

important in the evaluation of the river states at every computational point along a river

reach. The research shall generally provide basis for decision-making concerning the

flooding problem in Budalangi floodplains to the relevant authorities. Additionally

MIKE11 is a handy model that is useful in floodplain modelling. The study will serve as

a basis for future floodplain studies in Kenya.

1.5 SCOPE OF THE RESEARCH

This study is to be restricted to the last 20km reach of the Nzoia River in Budalangi

floodplain, which is prone to flooding.

3

The study shall involve the collection of the flow data at the upstream of the river reach,

the downstream water levels (Time series of lake levels), the river geometry data, and

topographical data and satellite images of flood scenes.

1.6 OBJECTIVES OF THE RESEARCH

1.6.1 Overall Objective of the Research.The overall objective of the research is to develop flood maps for different return periods

using MIKE 11-GIS interface in a GIS environment.

1.6.2 Specific Objectives of the Research.i) Visiting the stakeholders in the water sector to hold fora on flooding situation in

Budalangi.ii) To develop an inventory of spatial and hydraulic data and construct a MIKE 11 river model for Budalangi floodplains. iii) To construct a MIKE 11 river model for Budalangi floodplains and validate the

simulated flood maps by the use of satellite images.

1.7 LIMITATIONS

The main limitation of the research is in connection to the duration of the research,

which is to be carried within the specified academic calendar. The other limitation is

the low measurement consistency of the GPS instrument.

4

CHAPTER TWO

2.0 LITERATURE REVIEW

2.1 INTRODUCTION

This chapter discusses the literature related to river flood modelling. It particularly focuses on the fundamentals of the MIKE 11 model and the case studies that have employed the use of the MIKE 11 hydrodynamic river model.

No previous studies that have been carried out on the subject of river flood analysis using quasi two-dimensional hydrodynamic model in Budalangi or elsewhere in Kenyan rivers. (CAS Consultants., 2006).

Literature is fairly available on quasi two-dimensional floodplain modelling carried out in Europe, especially in the Netherlands and Belgium.

2.2 ABOUT MIKE 11 MODEL

MIKE 11, developed by Danish Hydraulic Institute (DHI) Water & Environment, is a

modeling package for the simulation of surface runoff, flow, floodplains, sediment

transport and water quality in rivers, and channels. The hydrodynamic module (MIKE11

HD) is commonly applied as a flood management tool simulating the unsteady flow in

branched and looped river networks and quasi two-dimensional flow on floodplains.

Once a model is established and calibrated, the impact of change of artificial or natural

origin of flood behavior can be quantified and displayed as change in flood level and

discharges (Kumar, 2005).

MIKE 11 is based on an effective numerical solution of the complete non-linear St-

Venant equation for 1-D flows.

DHI's MIKE 11 software package is a versatile and modular engineering tool for

modeling conditions in rivers, lakes/reservoirs, irrigation canals and other inland water

system (DHI, 2002).

MIKE 11 has an interface to GIS allowing for preparation of model input and

presentation of model output in a GIS environment

(www.dhisoftware.com/MIKE11/News/MIKE 11 Papers.htm).

5

2.2.1 Model Features

MIKE 11 is a modular engineering tool for modelling conditions in rivers, lakes and reservoirs, irrigation canals, and other inland water systems (DHI, 2008). It is designed for:

i) Flood risk analysis and mapping,ii) Design of flood alleviation systems,iii) Real-time water quality forecasting and pollutant tracking,iv) Real-time flood forecasting,v) Hydraulic analysis and design of structures, including bridges,vi) Drainage and Irrigation studies,vii) Optimization of river and reservoir operations,viii) Dam break analysisix) Water quality issues andx) Integrated groundwater and surface water analysis.

2.2.2 Model Physical Details

The MIKE 11 hydrodynamic module (HD) uses an implicit, finite difference scheme for the computation of unsteady flows in rivers and estuaries. The scheme is called 6-point Abbot Scheme (DHI, 2008). The module can describe subcritical as well as supercritical flow conditions through a numerical scheme that adapts according to the local flow conditions (in time and space).

The computational scheme is applicable for vertically homogeneous flow conditions extending from steep river flows to tidal estuaries.

2.2.3 Model Framework

MIKE 11 consists of a hydrodynamic core module and a number of add-on modules, each simulating certain phenomena in a river system (www.dhisoftware.com/MIKE11/News/MIKE 11 Papers.htm).

The modular structure offers great flexibility, because:

i) Each module can be operated separately,ii) Data transfer between modules is automatic,iii) Complex physical processes can be coupled (e.g. river morphology, sediment

re-suspension and water quality), andiv) Updating or expansion of existing installations or models with new modules is

simple.

6

2.3 CASE STUDIES

The following sections seek to explore previous researches that made use of MIKE 11 in the river flood modelling.

2.3.1 Fraser River (British Columbia) Flood Modelling

In 2006, Fraser Basin Council contracted Northwest Hydraulic Consultants (nhc) Ltd to develop a state-of-the art numerical model for the lower Fraser River, 170 km long. The model was based on detailed surveys of the river channel. The model was calibrated to known recorded floods and then used to calculate the water levels. MIKE 11 was used where over 1,200 river cross sections describing the main and side channels were used (www.cwra.org/Branches/British_Columbia/Assets/Runoff_April_2008.pdf).

Through the model results, the government of British Columbia funded the upgrading of

dykes and the model assisted in making decision on which dyke sections most critically

needed to be raised.

The nhc Ltd did not carry out the flood hazard mapping.

2.3.2 Flood Hazard Mapping for the Skeeria River at Terrace

Water Management consultants (WMC) were contracted by the city of Terrace in Canada in the year 2005 to prepare flood hazard mapping for floodplain areas within the city.

The scope of the work included setting up MIKE 11 hydrodynamic model and determining depths of flooding, erosion rates and potential avulsion paths. A hazard evaluation rating was prepared for floodplain zones and a colour-coded flooded hazard maps prepared. (www.cwra.org/Branches/British_Columbia/Assets/Runoff_April_2008.pdf).

Out of the model results appropriate development guidelines for each hazard area were recommended.

2.3.3 Dender and Demer Catchments in Belgium

For the Dender catchment (708 km2), the historical flood events of 1993, 1995 and 2002 were investigated and modelled. A 4m LiDAR DEM and flood satellite images for the catchment were available (Willems et al., 2003).

In this study, existing quasi-2D hydrodynamic model was used. It was implemented using the MIKE11 hydraulic modelling software. The validation of the model was achieved by the help of flood maps of the historical events after which composite hydrographs and limnigraphs were simulated for different return periods. The simulation results were then used to derive flood maps for specific return periods, which were used by Belgium government to make informed decision regarding flood management.

7

Though, it was realized that LiDAR DEM was of low quality and needed quality improvement. The limitations and advantages of various SAR imagery types were explored and established that ENVISAT ASAR and RADARSAT were shown to be better sources of SAR imagery for flood mapping.Noted also was that higher image resolution do not by default produce higher quality results. This is to the fact that some of them impose automatisation problems.

For the Demer catchment the modelling procedure is similar, the only difference was that a 10 m LiDAR DEM was available for this catchment

2.3.4 Entella Catchment in Italy

For this catchment, the historical flood events of 1999 and 2000 were investigated and modelled. A 1 m DEM was available (Willems et al, 2003).

The Entella, unlike the Dender and the Demer have no dykes. The Entella river flood model was implemented using River analysis System HEC-RAS (US Army Corps of Engineers-Hydrologic Engineering Centre). The implementation was made for the last portion of the river (about 10 km), where a plain with significant extension is located.

A long the portion of the river investigated, 65 cross-sections perpendicular to the axis of the river were topographically surveyed and superimposed to the DEM base. No useful SAR derived flood map was available. Thus the model was validated based on the historical information on the spatial extent of the floods in 1999 and 2000.

In this study, two methods were applied and compared: one, by the use of HEC-RAS and the topographic approach in order to forecast the boundaries of the flooded areas for different return periods, and two, using the DEM in the GeoRAS software. It was realized that the GIS/DEM based approach is more effective in hydraulic risk mapping due to its ability to provide water level depth estimates. (Willems et al, 2003).

2.3.5 Kushabhadra River Canal in India

A study was carried out on this canal with an aim of generating flood inundation scenarios using DEMs (ASTER and STRM) in hydrodynamic models (MIKE 11 and SOBEK) and then compare the flood extent maps derived using the satellite images.

Using MIKE 11and SOBEK hydrodynamic models, longitudinal profile of the study area, water level and routed discharge along the canal at different reaches were generated to know the flood inundation scenario. In this study, ASTER and STRM DEM were used to derive cross-sections in the river and the floodplain.

The results favoured the use of DEM derived from ASTER and the MIKE 11 model.

8

2.3.6 The Euphrates River Case Study

In this case study, Mike 11 model was employed to simulate flows in Euphrates River in Iraq. The stream length used for this case was 1.6 km. The study’s focus was the development of a MIKE 11 model based on surveyed stream cross-section data. The result of the study explains that the model gives a good simulation of the flow according to the comparison between the estimated and observed stage hydrograph.

Also, the comparison between this and the Uday model that was used for the same river explains that the MIKE 11 model gives better simulation (Kamel A.K, 2008).

2.3.7 Deductions Derived from the Case Studies

Out of the following studies it is clear that MIKE 11 hydrodynamic model is useful in river flow and floodplain modelling. The studies show that MIKE 11 is useful tool in the management of water resources especially in situations that requires critical and accurate decisions, for instance the sections of the dyke that requires urgent rehabilitation before the onset of the rain season.

9

CHAPTER THREE

3.0 METHODOLOGY

3.1 INTRODUCTION

This chapter seeks to explain the logical steps that shall be employed in the collection of

relevant field data and the techniques to be used in the analysis of the collected data.

3.2 DATA COLLECTION

3.2.1 Data RequirementsThe data requirement for the quasi-2D floodplain modelling includes:

i) Flow data- upstream boundary condition for the study river reach,

ii) Lake levels for the downstream boundary condition,

iii) Geometrical data (cross-sections) of the river channel,

iv) Topographical data (Toposheets, satellite images, DEM).

3.2.2 Data Collection TechniquesThe following methods shall be employed in the collection of the above-enumerated data:

i. Preliminary field surveys and observations.

ii. Study of relevant records e.g. satellite flood images showing

extent of flooding, flow data at upstream boundary of the study

river reach and the lake levels for the downstream boundary.

iii. Making visits to stakeholders in the water sector e.g. National

Water Conservation and Pipeline Corporation (NWCPC), Lake

Victoria North Catchment Authority and the Western Kenya

Community-Driven Development & Flood Mitigation Project,

Water Resources Management Authority (WRMA) and Regional

Centre for Mapping of Resources for Development (RCMRD).

iv. Field measurements

10

3.3 FIELD MEASUREMENTS

The field measurements shall include the determination of the river channel geometry by

the use of the Acoustic Doppler Current Profiler (ADCP) machine. The cross-sections

shall be extended to the outer embankment of the dykes by use of the level machine and

the two shall be amalgamated to produce a continuous cross-section from dyke to dyke.

The GPS instrument shall be used to collect point data along the river.

3.4 USE OF A GEOGRAPHICAL INFORMATION SYSTEM (GIS)

In this research, the modelling approach will use a Geographical Information System to

extract geographical information from the DEM (pre-processing task), and to visualize

the simulation results (post-processing task).

The preferential flow direction shall be derived from the DEM after which the cross

sections along the floodplain are to be derived from the DEM elevations along lines

perpendicular to the preferential flow direction (Willems et al, 2001).

3.5 COMPUTER MODELLING

In this research a quasi two- dimensional river flood modelling approach shall be

adopted. This will be based on an implementation of the one-dimensional hydraulic

MIKE 11 modelling system on the Budalangi floodplains and the river stretch serving the

plains. The following are the steps that shall be followed:

3.5.1 Initial Visualization of the Potential Flood Zones

In a first step the one-dimensional hydrodynamic model of the river network (without

floodplains) shall be simulated. The composite hydrographs of the upstream boundary

data (river flows) and downstream boundary data (water levels), for the highest return

period considered will be simulated for the purpose. The simulated water levels in the

river shall be extrapolated to the region outside the river bed, taking the dyke levels into

account. The extrapolation of water levels will be done with the help of a DEM of the

study area. The upstream hydrographs and downstream limnigraphs shall be derived for

specific return periods, based on ‘composite hydrograph method’ (Vaes et al, 2000).

Composite hydrographs and limnigraphs are constructed based on an extreme value

11

analysis of long-term time series of river discharges and downstream water levels using

WETSPRO tool.

3.5.2 Extraction of Topographical Information Topographical data needed in the hydraulic model shall be extracted from the DEM. First

the preferential flow direction in the floodplain will be determined and then the cross-

sections along the flood plains perpendicular to the preferential flow direction. The

DEM cross-sections will be corrected using the topographical surveys. This is done

because the accuracy of these levels affects the accuracy of the flood modelling.

(Willems et al., 2001).

3.5.3 Identification of the potential Risk Zones

The simulated water levels for the highest return periods are visualized and the missing

flood risk zones identified. Additional floodplains are then modelled for these zones. The

visualization will be done in Mike/GIS interface in ArcGIS. The visualization is done at

the calculation nodes and extrapolated to surrounding DEM grid points in all directions.

3.5.4 Visualization of the floodplain simulation

This involves the simulation of the quasi two-dimensional river model. The simulation results of the water levels are used for the mapping of the floods in the floodplains. Two types of maps shall be derived: maps for historical flooding events and maps for specific return periods. Flood maps for different return periods are as a result of simulation of the composite hydrographs.

The former type of maps shall be used in model validation by comparing the maps with

flooding satellite images for the same period. (Willems et al., 2001).

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REFERENCES

CAS Consultants (2006), Study on Causes and Effects of Floods in Nyanza and Western

Provinces Tana Basin and Taita-Taveta District: Draft Study Report.

DHI (2002), MIKE 11- A Modelling system for Rivers and Channels, User Manual,

Danish Hydraulic Institute, Hørsholm, Denmark.

DHI (2008), MIKE 11-a Modelling System for Rivers and Channels, Short Introduction

Tutorial, Danish Hydraulic Institute, Hørsholm, Denmark.

NWCPC (2008), Status Report on the Floods Problem at Budalangi-Bunyala District.

Kamel A.K, (2008), ‘Application of A hydrodynamic MIKE 11 model for the Euphrates

River in Iraq,’ In the Slovak Journal of Civil Engineering.

Kumar Shailesh Singh, (2005), Analysis of Uncertainties in Digital Elevation Models in

Flood (Hydraulic) Modelling. Thesis submitted to the International institute for Geo-

information science and Earth Observation.

Timbe L., (2007), River flooding analysis using quasi-2D hydraulic modelling and

geospatial data. PhD thesis Faculty of Engineering K.U.Leuven

Vaes G, Willems P, and Berlamont J. (2000), ‘Selection and composition of

representative hydrographs for river design calculations’, International conference on

‘Monitoring catchment water quantity and quality’, Gent, Belgium, September 2000.

Willems P., Christiaens K, Vaes G, Popa D, Timbe L, Berlamont J and Feyen J

(2001), ‘Methodology for River flood modelling by the quasi two-dimensional approach’,

in “Bridging the Gap: Meeting the World’s Water and Environmental Resources

Challenges”, ASCE Publications.

Willems P., G. Vaes, D. Popa, L. Timbe & J. Berlamont (2002), Quasi 2D River flood

modeling, In: River Flow 2002, D. Bousmar and Y. Zech (ed.), Swets & Zeitlinger, Lisse,

Volume 2, 1253-1259.

Willems P., Sylvia T., and Massimo B, (2003). Flood Risk and Damage assessment

using Modeling and earth observation techniques (FAME) Demer, Dender and Entella

service cases Report, ESA-DUP 2 small services Project, Spatial Application Division

KU Leuven, Belgium.

13

http://www.kuleuven.be/river.html, Accessed at 18:42 hrs on Wednesday 1st September

2008

www.unep.org/Training/downloads/PDFs/NRBMI_small.pdf accessed at 15:20 hours on

Monday 7th April 2008

http://en.wikipedia.org/wiki/Flood accessed at 1800 hrs Wednesday 1st September 2008

http:// www.dhisoftware.com/MIKE11/News/MIKE 11 Papers.htm

McLean D, Monica M, and Tamsin L, (2008), Fraser River Modeling: Canadian Water

Resources Association BC Newsletter April 2008. Available at:

http://www.cwra.org/Branches/British_Columbia/Assets/Runoff_April_2008.pdf ).

(March, 13, 2009 11:30)

14

APPENDICES

APPENDIX 1: Map of study Area

a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)a)

Map of Kenya showing the Nzoia River Basin

15

b) Distribution of Rainfall and Discharge Stations in NzoiaThe area of study is the downstream of the gauging station number 1EF01 as shown in the figure above.

16

APPENDIX 2: TIME SCHEDULE

1. Carrying out of the Literature Review.

2. Data collection from relevant organizations (Databases)

3. Field Data collection (Field Measurements).

4. Analysis of collected data using MIKE 11.

5. Research/Thesis discussions with Prof. Willems in Belgium.

6. Thesis compilation and Finalization.

7. Thesis Submission and defence.

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APPENDIX 3: SUMMARY OF COST ESTIMATES

S/No. 2 -Involves the cost of vehicle hire for transport from Moi University to Budalangi, fuel cost, hire for technical person to operate the equipment, hire of casuals and the driver’s and researcher’s D.S.A.

18

S.N Description Unit Cost (Kshs) Amount

1 River flow data And L. Victoria Levels data

River flow-FreeL.Levels@2000

2000.00

2 Field data collection at Budalangi

112,500.00

3 Processing of Maps Consolidated amount of 10,000

10,000.00

4 Acquisition of Satellite Images

2-ASTER Images (@6,400)

12,800.00

5 Trip to Belgium for compilation and discussion of thesis with Supervisor

200,000.00

6 Local Trips 10 trips @ 1,500 15,000.00

7 Expenses related to the Production of Thesis

- 20,000.00

SUB-TOTAL 487,500.00

Contingencies 5% of Total 2,438.00

TOTAL 489,938.00