NUMERICAL MODELLING OF SURFACE AND SUBSURFACE FLOW INTERACTIONS IN PAYA INDAH WETLAND OF SELANGOR D. E., MALAYSIA
BAHAA-ELDIN ELWALI ABDEL RAHIM ELWALI
THESIS SUBMITTED IN FULFILMENT OF THE REQUIREMENT FOR THE DEGREE OF DOCTOR OF PHILOSOPHY OF SCIENCE
(PH. D.)
FACULTY OF SCIENCE UNIVERSITY OF MALAYA
KUALA LUMPUR 2009
ii
PEMODELAN NUMERIKAL INTERAKSI ALIRAN PERMUKAAN DAN SUB- PERMUKAAN DI TANAH LEMBAB PAYA INDAH, SELANGOR DE, MALAYSIA
BAHAA-ELDIN ELWALI ABDEL RAHIM ELWALI
TESIS YANG DIKEMUKAKAN UNTUK MEMPEROLEH IJAZAH DOKTOR FASAFAH SAINS
FAKULTI SAINS UNIVERSITI MALAYA
KUALA LUMPUR 2009
iii
PREFACE
This thesis was prepared as one of the requirements for the Ph.D. Degree as well as a contribution to the formulation of the Paya Indah Water Resources Management Plan. The study has been carried out from March 2006 to December 2008. The Paya Indah Wetland Sanctuary with its ex-mining ponds at the southern portion and peat swamp forest at the northern portion may act as natural flood detention storage and therefore it is essential to understand the complex water balance of this wetland.
The research focused on the mathematical modelling approach to model the hydrology and the water balance of the Paya Indah wetland and the surrounding peat swamp forest. The mathematical model is based on the integrated hydrological modeling system, MIKE SHE.
This modeling system is particularly suited for wetland modeling because of its integration nature and the ability to count for both surface and subsurface flows and their interactions.
Current and future researches will undoubtedly improve understanding of the basic concepts involved in this modelling project and may lead to more sophisticated flow and/or transport modelling(s).
The modelling protocol and related procedures in this thesis are therefore validated and aimed to be used as a management tool, thus the model subject to continuous refinement as new data become available and new questions arise.
This Ph.D. thesis contributes to the literature via participation in different national and international conferences; and publication in a few journals. Selective papers may include:
Bahaa-eldin E. A. R., Yusoff I., Azmi M. J, and Zainuddin O. 2009. Numerical modelling of tropical wetland catchment using MIKE SHE system: Calibration and Validation. Water Resources Research. Submitted
Bahaa-eldin E. A. R., Yusoff I., Azmi M. J, and Zainuddin O. 2009. Application of MIKE SHE modelling system to set up a water balance for Paya Indah wetland. Journal of hydrology. Submitted
Bahaa-eldin E. A. R., Yusoff I., Azmi M. J, and Zainuddin O. 2009. Predictions of hydrological modification on Paya Indah Wetland in Malaysia. Water Resources Management. Submitted.
iv Bahaa-eldin E. A. R., Yusoff I., Azmi M. J, and Zainuddin O. 2009. Simulation of integrated surface-water/groundwater flow for a freshwater wetland in Selangor State, Malaysia. Geological Society of Malaysia, Bulletin 55: 95 – 100.
Bahaa-eldin E. A. R., Yusoff I., Azmi M. J, and Zainuddin O. 2007. MIKE SHE modelling of surface water and groundwater interaction. National Geoscience Conference. Kota Kinabalu, Sabah; Malaysia. 7-9 June. P5A-4.
Bahaa-eldin E. A.Rahim, Yusoff, I., Azmi M.J. and Zainudin O. 2006. Modelling of hydrological interactions at Paya Indah Wetland, Malaysia. Proceedings of the 2nd Mathematics and Physical Science Graduate Conference. Faculty of Science, Building, National University of Singapore. Singapore, 12 – 14 December.
v ACKNOWLEDGEMENTS
The production of this thesis was made possible by the complementary funding from two different bodies including the Malaysian Ministry of Sciences, Technology & Environment under IRPA grant No. 02-03-08-003-EA003 and the University of Malaya under the Fellowship Scheme. Thanks are extended to the Department of Geology, Faculty of Science, and University of Malaya for all the provided facilities and assistance.
My sincerest thanks are due to my Advisor Assoc. Prof. Dr. Ismail Yusoff for his constant guidance and encouragement throughout the study period. The author duly appreciates the cooperation and support of Hj. Mr. Azmi M. Jaffri the Head of Department of Drainage and Irrigation Department (DID) of Malaysia; Dr. Zainudin Othman from the Malaysian Nuclear Agency.
Special gratefulness and appreciation are due to the helpfulness and gentleness of Mr.
Salim from Drainage and Irrigation Department of Malaysia; Mr. Yagambaram V. (Baram) from Minerals and Geoscience Department of Malaysia/Selangor State Office; and Mr Ahamed Zaki from Malaysia Meteorological Department. I am also thankful Brother Mohammed who kindly and generously rescued the flow of work of this research project (Appendix K; Photo K.8).
I am so grateful for Ir. Miss Azizah Abdul Gadir and Ir. Mrs. Atikah Shafae from Drainage and Irrigation Department of Malaysia for their special treatment. A sincere gratitude is extended also to all the staff of Department of Geology of University of Malaya, Drainage and Irrigation Department of Malaysia and Minerals and Geoscience Department of Malaysia.
My final and special gratefulness and appreciation are due to my parents, sisters and brothers for their putting up with me and being patient all this while.
vi vi
vii ABSTRACT
MIKE SHE modelling system was used to simulate the surface and subsurface flow interactions at the Paya Indah wetland catchment which covers an area of 242.21 km2 and lies in Selangor State in west of Malaysian peninsular. The watershed hydrology has been changed considerably due to the increased anthropogenic activities, producing different hydro-ecological problems for the catchment. These include frequent peat forest fires and dropping of the surface water level in the Paya Indah lakes system. Being physically-based distributed hydrologic model, the MIKE SHE model set-up, therefore, requires a vast set of input data which precisely include rainfall, evapotranspiration, river cross-section, detailed soil hydraulic properties and aquifer characteristics. The model was calibrated and validated against three targets including surface water, channel flow and groundwater head.
The multi-criteria evaluation and hydrographs visual judgments revealed that the model performance was satisfactory which allowed running the water balance and assessing the impact of the predicted future scenarios. Results revealed that elevated rate of the evapotranspiration losses and the landuse change impacts considerably influence the water level in the Paya Indah lakes system at rechargeable area of peat cover. On contrast during both calibration and validation periods it was found that groundwater abstraction controlled the dynamics of the groundwater within a large zone covered most of the downstream area of the catchment. The impact of over-abstraction at the Megasteel Co. Ltd. property on surface water level of the Paya Indah lakes system was investigated. It was found that the exchangeable flow between unsaturated zone and saturated is very limited at the area of the lakes system due to occurrence of impermeable clay layer of 10 m – 15 m thick and of a low permeability of an average value of 4.8E-7 m/s which acts as barrier that controls exchangeable flow between the unsaturated and saturated zones at this part of the catchment. Nonetheless, it was found that the current rate of pumping had influenced the groundwater table to drop as low as ∼ 4.0 m below sea level within the influenced zone of the Megasteel pumping wells which in turn, may rise up the potentiality of seawater intrusion and deep aquifer collapse. Looking at the overall water balance it is clear that evapotranspiration accounted for the largest water loss of ∼ 60 % of the total rainfall. The model was slightly underestimated the total water balances by 0.45 % and 0.21 % the total rainfall for the calibration and validation periods respectively. Hydrological scenarios that likely might alter the quantity and timing of water exiting the Paya Indah wetland catchment were simulated with the validated model (baseline scenario) in order to evaluate their impacts on the watershed’s hydrology. In this context, decreasing of the North-Inlet- Canal (SWL1) inflow as a result of launching the flood mitigation new channel that diverts Cyberjaya water towards Klang River Basin is one of the expected impacts of the full development of the adjacent Cyberjaya City and E-village. While as the results revealed that the deep aquifer might deplete partially or totally depending on the quantity of the groundwater withdrawal.
viii PEMODELAN NUMERIKAL INTERAKSI ALIRAN PERMUKAAN DAN SUB-
PERMUKAAN DI TANAH LEMBAB PAYA INDAH, SELANGOR D.E., MALAYSIA
ABSTRAK
Sistem pemodelan MIKE SHE telah digunakan untuk mengsimulasi interaksi aliran air permukaan dan sub-permukaan di lembangan tanah lembab Paya Indah yang merangkumi kawasan seluas 242.21 km2 yang terletak di Negeri Selangor, di barat Semenanjung Malaysia. Hidrologi lembangan ini telah berubah secara ketara akibat peningkatan aktiviti antropogenik yang menyumbang kepada masalah hidro-ekologi lembangan. Ini termasuklah kekerapan kebakaran hutan paya bakau dan kejatuhan paras air di sistem tasik- tasik Paya Indah. MIKE SHE merupakan model hidrologi dasaran fizikal yang memerlukan pemasukan data yang banyak yang diantaranya termasuklah data kerpasan, evapotranspirasi, keratan rentas sungai, sifat hidraulik tanih dan ciri-ciri akuifer. Model ini telah dikalibrasi dan divalidasi dengan tiga sasaran kalibrasi termasuklah aras air permukaan, saliran dan air tanah. Penilaian yang dibuat menggunakan multi-kriteria dan pengvisualan hidrograf menunjukkan kebolehan model ini adalah memuaskan dan membolehkan kajian keseimbangan air dan kesan senario masa depan diramalkan. Hasil kajian ini menunjukkan peningkatan kadar kehilangan air secara evapotranspirasi dan perubahan guna tanah memberi perubahan ketara kepada aras air di dalam sistem tasik Paya Indah di kawasan imbuhan yang ditutupi oleh tanah gambut. Secara perbandingannya pula, sepanjang tempoh masa kalibrasi dan validasi adalah didapati pengambilan air tanah yang mengawal dinamik air tanah di dalam zon luas yang merangkumi sebahagian besar kawasan hilir lembangan. Kesan pengambilan air tanah secara ketara oleh Syarikat MegaSteel Sdn. Bhd kepada aras air di tasik-tasik Paya Indah juga dikaji. Adalah didapati aliran yang bertukarganti di antara zon tak tepu dan zon tepu amat terhad bagi kawasan tasik dimana terdapatnya lapisan lempung tak telap yang berketebalan antara 10 m-15 m dengan kadar ketelapan yang rendah dengan nilai puratanya adalah 4.8E-7 m/s yang juga bertindak sebagai penghalang kepada aliran tukarganti di antara zon tak tepu dan zon tepu di sebahagian lembangan ini. Apapun adalah didapati kadar pengepaman air tanah pada masa ini telah menyebabkan aras air tanah jatuh sedalam 4.0 m di bawah paras laut bagi kawasan yang dipengaruhi oleh telaga pengepaman Megasteel yang berpotensi besar menjadi penyebab kepada intrusi air laut dan kegagalan akuifer dalam. Berdasarkan keseimbangan air secara keseluruhan adalah jelas didapati evapotranspirasi menjadi penyumbang besar kepada kehilangan air lembangan sehingga mencapai 60 % dari keseluruhan kerpasan. Model ini memberi kurangan anggaran keseimbangan air semasa proses kalibrasi dan validasi masing-masing sebanyak 0.45% dan 0.21 % dari jumlah hujan keseluruhan. Model yang telah divalidasi digunakan untuk melihat senario hidrologi yang bakal mengubah kuantiti dan masa kedapatan air di lembagan tanah lembab Paya Indah bagi menilai kesan perubahan kepada tindakbalas hidrologi lembangan. Bagi kontek ini, pembangunan sepenuhnya kawasan Bandar Cyberjaya dan E-Village yang bersebelahan dengan model lembangan akan meyebabkan terbentuknya saliran pemulihan baru yang mengalihkan aliran air dari Cyberjaya ke lembagan Sg. Klang dan menghilangkan kemasukan air dari saluran North-Inlet (SWL1). Disamping itu, keputusan pemodelan menunjukkan akuifer dalam mungkin mengalami kejatuhan secara separa atau keseluruhan bergantung kepada kuantiti pengeluaran air tanah.
ix
CONTENTS
Page
PREFACE iii
ACKNOWLEDGEMENTS v
DECLARATION vi
ABSTRACT vii
ABSTRAK viii
CONTENTS ix
LIST OF FIGURES xiv
LIST OF TABLES xxi
LIST OF PHOTOGRAPHS xxiii
LIST OF SYMBOLS AND ABBREVIATIONS xxv
CHAPTER I INTRODUCTION 1.1 Description of the Study Area 1
1.1.1 Geology 3
1.1.2 Hydrology 5
1.1.3 Groundwater status 8
1.2 Objectives 9
1.3 Scope of the Study 10
1.4 Importance of the Study 10
1.5 Modeling Approach 11
x CHAPTER II LITERATURE REVIEW
2.1 Hydrologic Cycle 13
2.2 Watershed Hydrology 14
2.3 Water Resources Management Problems 17 2.3.1 Water resources problems in Malaysia 18
2.4 Soil Hydraulic Parameters 23
2.5 Ramsar Convention on Wetlands 25
2.5.1 Ramsar listed wetlands of Malaysia 26
2.6 Modelling 27
2.6.1 Watershed models 30
CHAPTER III MODELLING TOOL
3.1 Hydrological Description 46
3.2 Hydrological Description 47
3.2.1 Interception and evapotranspiration components 49 3.2.2 Overland and channel flow component 53
3.2.3 Unsaturated zone components 56
3.2.4 Saturated zone components 58
CHAPTER IV MODEL INPUT DATA
4.1 Hydro-meteorological Data 63
4.1.1 Rainfall 63
3.1.3 Evapotranspiration 66
4.2 Landuse and Vegetation 67
4.3 Surface Topography 69
4.4 Overland Flow and River Network 72
4.4.1 Overland flow 73
4.4.2 Flooded area 74
xi 4.4.3 Cross sections and bathymetry data 75
4.5 Unsaturated Zone 77
4.5.1 Types of soils 77
4.5.2 Soil water 78
4.5.3 Soil sampling and insitu measurements 81
4.5.4 Soil characterization 84
4.5.5 Presentation of soil tests results 89
4.6 Saturated Zone 91
4.6.1 Geological model 91
4.6.2 Aquifers characteristics 95
4.6.3 Interactions between the surface and 96 subsurface flow
4.6.4 Groundwater abstraction 96
4.7 Surface water and Groundwater Timeseries Data 98
4.8 Model Set-up 98
4.8.1 Boundary conditions 99
4.8.2 Surface water flow system 103
4.9 Conceptual Model 105
4.10 Model Domain and Discretization 108
4.11 Model Development 110
4.11.1 Simulation time step 111
4.11.2 Model Calibration 112
4.11.3 Model Validation 112
4.11.4 Model Performance 112
CHAPTER V MODEL CALIBRATION AND VALIDATION
5.1 Calibration 117
5.1.1 Calibration targets 118
5.1.2 Primary calibration parameters 119
5.2 Calibration Results 120
5.2.1 Simulation of surface water level 120
5.2.2 Simulated groundwater heads 127
xii
5.2.3 Simulation of channel flow 132
5.3 Assessment of Calibrated Model 135
5.3.1 Performance of the coupled model 136 5.3.2 Assessment of model predictive capability 141
5.4 Validation 144
5.4.1 Validated surface water flow 145
5.4.2 Validated groundwater head 150
5.4.3 Validation of channel flow 151
5.5 Assessment of the Validated Model Performance 155
5.5.1 Performance of the coupled model 155 5.5.2 Assessment of model predictive capability 157
5.6 Sensitivity Analysis 159
5.6.1 Effect of increment of evapotranspiration rate 162 5.6.2 Effect of depletion of the inflow 165
CHAPTER V1 MODEL OUTPUTS
6.1 Water Balance 170
6.2 Saturated and Unsaturated Flow Interactions 176
6.2.1 Overland flow 176
6.2.2 Flow exchange between unsaturated 177 and saturated zones
6.2.3 Saturated zone and river lateral flow 180 6.3 Hydrological Impact of Groundwater Abstraction 181
CHAPTER V1I SCENARIOS
7.1 Cyberjaya Development Flagship Zone: Phase II 186
7.2 Cyberjaya Full Development and the E-village 188
7.3 Replacement of Peat Layer 191
7.4 Groundwater over- abstraction 194
xiii CHAPTER V1II SUMMARY AND CONCLUSIONS
8.1 Summary 196
8.2 Conclusions 197
CHAPTER IX RECOMMENDATIONS
9.1 challenging Issues 201
9.2 Recommendations 202
REFERENCES 204
APPENDICES
A Criteria for the Designation of Wetlands of International 220 Importance
B Ramsar-nominated Wetlands of Malaysia 221
C Polynomial Approximation of IDF Curves 226
D Monthly Rainall atthe Paya Indah Wetland Catchment 232 E Monthly Evapotranspiration at the Paya Indah 233
Wetland Catchment
F River-cross Section Data 234
G Malaysian Soil Series 237
H Soil Profile Definition and Soil Parameters used in the Model 238
I Engineering Borehole Log for PI 1 241
J Pumping Test Data 244
K Album 254
xiv LIST OF FIGURES
Figure No. Page
1.1 Index map of the Study Area 2
1.2 Geological and Location Map of the Study Area 4
1.3 Components of the Paya Indah Lakes System 6
1.4 Land Phase Components of the Hydrologic Cylce 12
2.1 A System Representation of the Hydrologic Cycle 14 2.2 Hydrologic cylce components with golobal annual 15
average water balance given in units relative to value of 100 for the precitiparion rate on land
2.3 Classification of hydrologic models 28
2.4 The modelling protocol and schedule proposed 29
for the present study
3.1 Schematic Representation of MIKE SHE Model 48
3.2 Schematic Diagram of Interception and Evapotranspiration 49 4.1 Estimated Rainfall Fields for the Catchment using 64
Thiessen-polygon Method
4.2 Hyetograph of the Paya Indah Wetland Catchment 65
4.3 Daily Evapotranspiration for the Paya Indah 66
Wetland Catchment
4.4 Landuse Map of the Paya Indah Wetland Catchment 67
4.5 Topography Data 70
4.6 Layout of Paya Indah Lakes System showing the Locations 71 of the Spot Level Data
4.7 Topographic Model of the Paya Indah Wetland Catchment 71 4.8 Zooming-in for Set-up of Channel Flow Network the Location 72
of Hydrodynamic Boundaries, Cross-sections, Culvert and the Lotus Lake Outlet Controlled Gate
xv 4.9 Flooded Areas within of the Paya Indah Wetland 74
Catchment: Lakes names and their representing code number
4.10 Bathymetry model 75
4.11 Longitudinal Profile for Tin Lake, Tin-Perch-Connect 76 and Perch Lake
4.12 Longitudinal Profile for Tin Lake, Tin-Perch-Connect 77 and Chalet Lake
4.13 Soil Map of the Paya Indah Wetland Catchment 78
4.14 Overview of Soil Volume/Weight Relationship: “V” and “W” 79 represent volume and weight, respectively; “soil” refers to
the fine earth fraction (any combination of sand, silt and clay minerals mixed with soil organic matter and pores), but excludes coarse fragments (CF); “soil particles” refer to fine earth minerals and organic matter. Solid refers to fine earth +CF. Total volume refers to fine earth,
CF and pores.
4.15 Locations of Soil Sampling and Insitu Measurements 82 4.16 Infiltration Test for the Selangor-Kanchung Series. 88
Location: Kg Sg Manggis (Mangostine River Village)
4.17 Presentation of a Geological Cross-section across 91 the Modelled Area
4.18 Thickness of the Geological Layer 1 93
4.19 Thickness of the Geological Layer 2 94
4.20 Thickness of the Geological Layer 3 94
4.21 Location of Monitoring and Production Wells within 97 the Modelled Area
4.22 Boundary Conditions for the Study Area 100
4.23 Conceptual Model of the Paya Indah Wetland Catchment 107
4.24 Model Domain and Grid 109
4.25 Mesh Discretization for the Study Area 110
xvi 5.1 Calibrated Water Level Hydrograph for North-Inlet-Canal (SWL1) 121 5.2 Calibrated Water Level Hydrograph for Visitor Lake 122 5.3 Calibrated Water Level Hydrograph for Main Lake 122 5.4 Calibrated Water Level Hydrograph for Driftwood Lake 123 5.5 Calibrated Water Level Hydrograph for Perch Lake 123 5.6 Calibrated Water Level Hydrograph for Marsh Lake 124 5.7 Calibrated Water Level Hydrograph for Crocodile Lake 124 5.8 Calibrated Water Level Hydrograph for Hippo Lake 125 5.9 Calibrated Water Level Hydrograph for Chalet Lake 125 5.10 Calibrated Water Level Hydrograph for Typha Lake 126 5.11 Calibrated Water Level Hydrograph for Lotus Lake 126 5.12 Calibrated Water Level Hydrograph for Lotus-Outlet (SWL2) 127 5.13 Calibrated Groundwater Head Hydrograph for BH1 128 5.14 Calibrated Groundwater Head Hydrograph for BH2 129 5.15 Calibrated Groundwater Head Hydrograph for BH3 129 5.16 Calibrated Groundwater Head Hydrograph for BH4 130 5.17 Calibrated Groundwater Head Hydrograph for BH5 130 5.18 Calibrated Groundwater Head Hydrograph for BH6 131 5.19 Calibrated Groundwater Head Hydrograph for BH7 131 5.20 Calibrated Groundwater Head Hydrograph for BH8 132
5.21 Calibrated Channel Flow Hydrograph for SWL1 133
5.22 Hyetograph and Hydrographs for SWL1 133
5.23 Calibrated Channel Flow Hydrograph for SWL2 134
5.24 Hyetograph and Hydrographs for SWL2 135
xvii 5.25 Scattered Plot for the Observed and Simulated Channel Flow 142
at SWL1 during Calibration Period
5.26 Scattered Plot for the Observed and Simulated Channel Flow 143 at SWL1 during Calibration Period
5.27 Validated Water Level Hydrograph at Visitor Lake 146 5.28 Validated Water Level Hydrograph at Main Lake 146
5.29 Validated Water Level Hydrograph at Tin Lake 147
5.30 Validated Water Level Hydrograph at Crocodile Lake 147 5.31 Validated Water Level Hydrograph at Hippo Lake 148 5.32 Validated Water Level Hydrograph at Chalet Lake 148 5.33 Validated Water Level Hydrograph at Typha Lake 149 5.34 Validated Water Level Hydrograph at Lotus Lake 149 5.35 Validated Groundwater Head Hydrograph at BH3 150 5.36 Validated Groundwater Head Hydrograph at BH5 151 5.37 Validated Channel Flow Hydrograph for the Reach 152
of Langat River
5.38 Validated Channel Flow Hydrograph for SWL2 153
5.39 Hyetograph and Validation Hydrographs for Reach 154 of the Langat River
5.40 Hyetograph and Validation Hydrographs for SWL2 154 5.41 Scattered Plot for the Observed and Simulated Channel Flow 158
at the Reach of Langat River during Validation Period
5.42 Scattered Plot for the Observed and Simulated Channel Flow 158 at SWL1 during validation Period
5.43 Sensitivity Run for Assessing the Effect of ET Increment 163 on Surface water Level at SWL1
5.44 Sensitivity Run for Assessing the Effect of ET Increment 163 on Surface water Level at Typha Lake
xviii 5.45 Sensitivity Run for Assessing the Effect of ET Increment 164
on Surface water Level at BH3
5.46 Sensitivity Run for Assessing the Effect of ET Increment 164 on Surface water Level at BH5
5.47 Sensitivity Run for Assessing the Effect of Flow Depletion 166 at Visitor Lake
5.48 Sensitivity Run for Assessing the Effect of Flow Depletion 167 at Main Lake
5.49 Sensitivity Run for Assessing the Effect of Flow Depletion 167 at Crocodile Lake
5.50 Sensitivity Run for Assessing the Effect of Flow Depletion 168 at Chalet Lake
5.51 Sensitivity Run for Assessing the Effect of Flow Depletion 168 at Lotus Lake
5.52 Sensitivity Run for Assessing the Effect of Flow Depletion 169 at SWL2
6.1 Water Balance for Paya Indah Wetland Catchment (∼ 242 km2) 171 for the Simulation Period 1/July/1999 to 31/October/2004
6.2 Water Balance for Paya Indah Wetland Catchment (∼ 242 km2) 172 for the Simulation Period 1/August/2007 to 2/August/2008
6.3 Distribution of Actual evapotranspiration at Paya Indah Wetland 174 Catchment during a Normal Day in the Wet Season
6.4 Distribution of Actual evapotranspiration at Paya Indah Wetland 175 Catchment during a Normal Day in the Dry Season
6.5 Depth of Overland Water during a Normal Day in Wet season 177 6.6 Unsaturated-Saturated Zones Flow Exchange during a Normal 178
Day during Wet Season.
6.7 Unsaturated-Saturated Zones Flow Exchange during a Normal 179 Day during Dry Season.
6.8 Flow Exchange between Saturated Zone and Channel Flow 180
6.9 Impact of Groundwater Pumping at the Megasteel Wells on 182 the Groundwater Head Elevation
xix 6.10 Impact of Groundwater Pumping at the Megasteel on 183
Groundwater Flow Direction
7.1 Layout of Baseline Scenario 186
7.2 Layout of Phase II of Cyberjaya Development Scenario 187 7.3 Impact of Phase II Development of Cyberjaya on 188
the Groundwater Table in the Peat Layer
7.4 Effect of Depletion of the Inflow from Cyberjaya on Main Lake 189 7.5 Effect of Depletion of the Inflow from Cyberjaya 189
on Crocodile Lake
7.6 Effect of Depletion of the Inflow from Cyberjaya on Chalet Lake 190 7.7 Effect of Depletion of the Inflow from Cyberjaya on Lotus Lake 190 7.8 Impact of Full Development of Cyberjaya and E-village on the 191
Groundwater Table in the Peat Layer
7.9 Layout of the Peat Basin 192
7.10 Effect of Replacement of the Peat Layer by a Low 193 Permeability Soil Material on Tin Lake
7.11 Effect of Replacement of the Peat Layer by a Low 193 Permeability Soil Material on BH3
7.12 Effect of Replacement of the Peat Layer by a Low 194 Permeability Soil Material on BH5
C.1 Rainfall Intensity-duration-frequency (IDF) Curve for the 227 Paya Indah Wetland Catchment of the Pumping Test
C.2 Frequency of Storm Events in 2-years Period 228
C.3 Frequency of Storm Events in 5-years Period 228
C.4 Frequency of Storm Events in 10-years Period 229
C.5 Frequency of Storm Events in 25-years Period 229
C.6 Frequency of Storm Events in 50-years Period 230
C.7 Frequency of Storm Events in 25-years Period 230
xx
J.1 Location of the Pumping Test 244
J.2 Result of constant rate pumping test at Observation well PI1 246 J.3 Result of constant discharge pumping test at Observation well PI1 248
xxi LIST OF TABLES
Table No. Page
1.1 Names and lengths of the Hydrologic System Components 7 of the Paya Indah Wetland Catchment Model
2.1 Water Resources in Malaysia 19
4.1 Rainfall Area Weighted Factors for the Paya Indah Wetland 64 Catchment
4.2 Properties of Vegetation within the Paya Indah Wetland 68 Catchment
4.3 Soil Hydraulic Properties used in for the Model 89 4.4 Characteristics of Shallow and Deep Aquifers at the Paya Indah 95
Wetland Catchment
4.5 Roughness Coefficient (Manning’s coefficient) used for 104 the Channels in the study area
5.1 Statistical Evaluation Criteria for the Calibrated Model 139 5.2 Evaluation of the Predictive Accuracy of the Calibrated Model 141 5.3 Statistical Evaluation Criteria for the Validated Model 156 5.4 Evaluation of the Predictive Accuracy of the Validated Model 157 5.5 Model Parameters and Statistical Evaluation of Each Calibration 160
and Validation Simulation Run
5.6 Sensitivity of Different Flow Rate Modifications at SWL1 166 6.1 Water Balance Estimation at the Paya Indah Wetland 173
Catchment: Contribution of each Component
7.1 Impacts of Groundwater Over-abstraction Scenarios 195 A.1 Criteria for the Designation of Wetland of International 220
Importance
C.1 Coefficients of the Fitted IDF Equation for Kuala Lumpur 227
C.2 Rainfall Intensity-duration-frequency (IDF) Estimation for the 231
xxii Paya Indah Wetland Catchment
D.1 Monthly Rainfall at for the Paya Indah Wetland Catchment 232 E.1 Monthly Evapotranspiration at for the Paya Indah Wetland 233
Catchment
F.1 Dimensions and Basic Statistics for the Cross sections of the 234 River Network for the Modelled catchment
G.1 Malaysian Soil Series 237
H.1 Soil Profile Definition and Soil Parameters used in the Model 238
I.1 Engineering Borehole Log for PI1 241
J.1 Data of Constant Rate Pumping Test a the Observation Well PI1 245 J.2 Data of the Recovery Test a the Observation Well PI1 247 J.3 Determination of Hydraulic Conductivity for the Deep Aquifer 249
Using Constant Head Permeability Test at Borehole PI1
J.4 Determination of Hydraulic Conductivity for the Second Layer 250 Using Constant Head Permeability Test at Borehole PI2
J.5 Determination of Hydraulic Conductivity for the Shallow Aquifer 251 Using Constant Head Permeability Test at Borehole PI3
J.6 Measurements of Ground Subsidence at Megasteel Co. Ltd 252 Area for the period 2001 – 2006
J.7 Measurements of Ground Subsidence at Megasteel Co. Ltd 253 Area for the period 2000 – 2007
xxiii LIST OF PHOTOGRAPHS
PHOTO No. Page
K.1 Kick-start Visit1 254
K.2 Kick-start Visi2 255
K.3 Peat Big Days 256
K.4 Infiltration Test at Kg Sg Manggis 257
K.5 Infiltration Test near the marsh Lake 258
K.6 Retrieving Groundwater Data of BH3 259
K.7 Checking the Coordinates of BH6 before Retrieving the 260 Groundwater Level Data from the Automatic Logger.
K.8 Heading towards BH6 across the Langat River 260
K.9 Gauging at SWL1 261
K.10 Gauging at SWL2 262
K.11 Automatic logger at SWL1 263
K.12 Automatic logger at SWL2 264
K.13 Automatic logger at Main-Visitor Connection 264 K.14 Inflow from Cyberjaya City on a Rainy Day. The North South 265
Expressway Central Link (NSECL) also appears on the picture
K.15 Visitor Lake Overview 266
K.16 Main Lake Overview 266
K.17 Culvert of the Main-Palm Connection 267
K.18 Main-Palm Connection heading towards the Lotus Lake 267
K.19 Overview of the Main and Driftwood Lakes 268
K.20 Tin-Driftwood Connection 268
K.21 Padi (ex-) Lake and it Functionless Culvert 269
xxiv
K.22 Swamp-hen (semi-) Lake Overview 270
K.23 Connection Point between Lotus-Swamp-hen Connection and 271 Lotus Lake
K.24 Typha Lake Overview 272
K.25 Lotus lake Overview 272
K.26 Lotus-outlet Control Gate: Front View 273
K.27 Lotus-outlet Control Gate: Front View 273
K.28 Outlet heading towards Langat River 274
K.29 Wildlife Habitats 274
K.30 Deep inside the Peat Paradise’s Blanket 275
xxv LIST OF SYMBOLS AND ABBREVIATIONS
b.s.l.: below the sea level
BH: Borehole
CE: Coefficient of efficiency
DID: Drainage and Irrigation Department of Malaysia ET: Actual Evapotranspiration
Evap: Evaporation Exfilt: Exfiltration
GIS: Geographic information system Infilt: Infiltration
k: Hydraulic conductivity
Kg: Kampung (village)
KLIA: Kuala Lumpur International Airport
m: Meter
M: The reciprocal of Manning’s n
MAE: Mean average error
ME: Mean error
MLD: Mined Land
MMD: Malaysia Meteorological Department
n: Manning’s number
NSECL: North-South Expressway Central Link
OL: Overland flow
P: Probability
P: Precipitation
xxvi PRG: Perang soil series
QG,in: Groundwater flow into the model area QG,out: Groundwater flow out of the model area
QS: Surface water inflow
QS,out: Surface water flow out of the model area
R: hydraulic radius
R: Coefficient of correlation
R2: Pearson type-I distribution index RMSE: Root mean square error
Sc: Storage coefficient of groundwater
S: channel bed slope
SBM. Serdang-Bungor-Munchong soil series
Sg: Sungai (River)
SKG: Selangor-Kanchung soil series STDres: Standard deviation of the residuals
SZ: Saturated zone
UZ: Unsaturated zone
T: Transmissivity
Trans: Transpiration
V: Flow velocity
∆S: Change in storage of surface water, unsaturated zone and groundwater (Ss+(Suz+(S sz)
xxvii
