Impounded Water Bodies Modelling and Simulation

By Salisu Dan’azumi and Supiah Shamsudin

This book enhances knowledge on Impounded Water Bodies (IWB) systems of the interested parties. They include academicians, scholars, scientist, researchers, engineers, undergraduate and postgraduate students. Specifically this book is valuable for everyone involved in water, hydrology, environment, civil engineering and other related disciplines. This book emphasized modelling and simulation of IWB particularly; Reservoir and Detention Pond, in relation to the two major hydrological problems; Flood and Water Pollution. The knowledge presented is useful for hydrological systems real phenomenon replication and prediction. This book also provides IWB general overview, in terms of the preliminary and state of the art analysis which may trigger the interest for further research and investigations. The IWB related factors were integrated to provide the quantitative framework, alternative approaches and valuable outcomes that lead to worthy policy establishment. This book covers topic related to nutrient (phosphorus) loadings estimation using the new version of Event-Based Stochastic Model in reservoir systems. The detention pond systems modelling using Analytical Probabilistic Models (APM) and the optimization of detention time using Particle Swarm Optimization (PSO) are elaborated. It is hoped that the book provides useful knowledge in pursuit of the IWB sustainable development.

Dr Supiah Shamsudin is an Associate Professor in Water Resources and Hydrology at the Razak School of Engineering and Advanced Technology, Universiti Teknologi Malaysia - Kuala Lumpur, Malaysia. She obtained Bachelor of Science (Civil Engineering) from University of Miami, USA and Master of Science (Hydrology and Water resources) from University of Nebraska - Lincoln, USA. She later obtained Doctor of Philosophy (PhD) in Civil Engineering from Universiti Teknologi Malaysia in 2003. Her main specialization is Impounded Water Bodies Engineering and Management. Her research interest include intelligent detention pond design, watershed and reservoir management under uncertain environment, environmental hydrology, reservoir eutrophication, fuzzy and risk related approaches and multicriteria decision support for water resources systems. She had extensive involvements in international peer reviewed indexed journal publications and presented at many national and international conferences.

Dr Salisu Danazumi is currently a Senior Lecturer in the Department of Civil Engineering, Bayero University Kano - Nigeria. He holds a Bachelors degree (Civil Engineering) and Masters degree (Water Resources and Environmental Engineering) from Bayero University Kano - Nigeria in 1998 and 2006 respectively. He obtained a PhD degree in Hydrology from Universiti Teknologi Malaysia in 2012. His research interest include: multi-objective optimization of water resource systems using particle swarm optimization, risk and uncertainty analysis and surface water quality modelling. He has authored and co-authored many papers in international peer reviewed journals and conferences.

• Language: English
• Publisher: Xlibris AU
• Release date: May 2, 2014
• ISBN: 9781493134991

Salisu Dan’azumi

Dr Supiah Shamsudin is an Associate Professor in Water Resources and Hydrology  at the Department of Civil Engineering, Razak School of Engineering and Advanced Technology, Universiti Teknologi Malaysia- Kuala Lumpur, Malaysia. She holds a Bachelors degree (Civil Engineering) from University of Miami, USA and Masters degree (Hydrology and Water resources) from University of Nebraska-Lincoln, USA. She later obtained Doctor of Philosophy (PhD) in Civil Engineering from Universiti Teknologi Malaysia in 2003. Her main specialization is Impounded Water Bodies  Engineering and Management. Her research interest include intelligent detention pond design, watershed and reservoir management under uncertain environment,  environmental hydrology, reservoir eutrophication,   fuzzy & risk related approaches and multicriteria decision support  for water resources systems. She had extensive involvements in international peer reviewed indexed journal publications and presented at many national and international conferences.   Dr Salisu Dan’azumi is currently a Senior Lecturer in the Department of Civil Engineering, Bayero Univerversity Kano-Nigeria. He holds a Bachelors degree (Civil Engineering) and Masters degree (Water resources and environmental engineering) from Bayero University Kano in 1998 and 2006 respectively. He proceeded to University Teknologi Malaysia and obtained a PhD degree (Hydrology) in 2012. His research interest include: multi-objective optimization of water resource systems using particle swarm optimization, risk and uncertainty analysis and surface water quality modelling. He has authored and co-authored many papers in international peer reviewed journals and learned conferences

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Copyright © 2014 by Supiah Shamsudin and Salisu Dan’azumi.

Library of Congress Control Number:   2014904158

ISBN:   Hardcover   978-1-4931-3497-7

   Softcover   978-1-4931-3498-4

   eBook   978-1-4931-3499-1

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Rev. date: 04/29/2014

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CONTENTS

CHAPTER 1

Introduction

1.1   Flood Problems in Malaysia

1.2   Water Pollution Problems in Malaysia

1.3   Reservoir Problems in Malaysia

1.4   Detention Pond Problems in Malaysia

1.5   The Needs for Stormwater Management and Control

1.5.1   Changes to Streamflow

1.5.2   Water Quality Impacts

1.5.3   Changes to Stream Geomorphology

1.5.4   Impacts to Aquatic Habitat

1.6   Point and Non-Point Source Pollution

1.7   Non-Point Source Pollution Control Strategies

1.8   Importance of Impounded Water Bodies (IWB) Study

CHAPTER 2

Impounded Water Bodies (IWB) Overview

2.1   Reservoir Water Quantity and Quality

2.1.1   Hydrological Considerations

2.1.2   Surface Water Pollution

2.1.3   Reservoir Eutrophication.

2.1.4   Non-Point Sources Pollution

2.2   Detention Pond Water Quantity and Quality

2.2.1   Detention Pond as Runoff Quantity Control

2.2.2   Detention Ponds as Runoff Quality Control

2.2.3   Sedimentation and Pollutants Removal in Detention Ponds

2.3   Nutrient Loadings and Limiting Factor

2.3.1   Nutrient Budget and Loadings

2.3.2   Nutrient—Phosphorus as a Limiting Factor

2.3.3.   Phosphorus and Nitrate Compounds

2.3.4   Phosphorus and Nitrate Risk

2.4   Types of Stormwater Detention Facilities

2.4.1   Detention and Retention Facilities

2.4.2   Wet and Dry Ponds

2.4.3   Above-Ground and Under-Ground Detention

2.4.4   On-Line and Off-Line Detention

2.4.5   Regional and On-Site Detention

2.4.6   Independent and Interconnected Ponds

CHAPTER 3

Impounded Water Bodies Modelling And Optimization Overview

3.1   Continuous Simulation

3.2   Analytical Probabilistic Models in Detention Pond Design

3.3   Optimization in Detention Pond Design

3.4   Evolutionary Multi-Objective Optimization

3.5   Particle Swam Optimization (PSO)

3.6   PSO Applications

3.7   Nutrient Loading Models

3.7.1   CREAMS

3.7.2   AGNPS

3.7.3   Vollenweider Model

3.8   Erosion Model—Universal Soil Loss Equation (USLE)

CHAPTER 4

Impounded Water Bodies Basic Design Concepts

4.1   Annual Runoff Volume (ARV) Estimation—First Principal

4.2   Streamflow Measurement—Velocity - Area Method

4.3   Peak Discharge Estimation—Rational Method

4.4   Polynomial Approximation of Intensity-Duration-Frequency (IDF) Curve

4.5   Unit Hydrograph

4.5.1   Unit Hydrograph—Changing of Duration using S-Curve

CHAPTER 5

Hydrological Discharge Estimation And Routing

5.1   Time - Area Method

5.2   Stage - Discharge Relationship

5.3   Flood Routing

5.3.1   Reservoir Routing

5.3.2   River/Stream Routing

5.4   Urban Storm Water Management (MSMA)

CHAPTER 6

Data Collection And Laboratory Testing

6.1   Water and Sediment Manual Sampling

6.2   Automatic Stormwater Sampling

6.3   Laboratory Analysis

6.4   Water Level and Flow Data

6.5   Soil Erodibility Factor, K Data

CHAPTER 7

Rainfall Statistics In Malaysia

7.1   Introduction

7.1.1   Study Area for Rainfall Analysis

7.1.2   Study Catchments for APM and PSO Applications

7.2   Estimation of Runoff Coefficient and Depression Storage for the Catchments

7.3   Rainfall Data Collection

7.3.1   Analysis of Rainfall Data

7.3.2   Rainfall Depths

7.3.3   Rainfall Durations

7.3.4   Rainfall Intensities

7.3.5   Storm Separation Times

7.4   Goodness-of-Fit Test

CHAPTER 8

Reservoir Water Quality Preliminary Assessments

8.1   Layang Reservoir Site Description

8.2   Nutrients Background Studies

8.3   Nutrient—Phosphorus and Nitrate

8.4   Related Water Quality Parameters—Temperature, DO, pH and SS

8.4.1   Temperature

8.4.2   Dissolved Oxygen (DO)

8.4.3   pH

8.4.4   Suspended Solids (SS)

8.4.5   Limiting Factor

CHAPTER 9

Reservoir Modelling And Simulation

9.1   Phosphorus Loadings Estimation Using Event-Based Stochastic Model.

9.2   Runoff Discharges Estimation Using MIKE11

9.3   Sediment Yield Estimation Using Modified Universal Soil Loss Equation (MUSLE)

CHAPTER 10

Detention Pond Modelling And Optimization

10.1   Modelling and Optimization of Detention Time in Dry Detention Ponds

10.2   Development of Analytical Probabilistic Model (APM) Parameters

10.3   Development of the APM for Runoff Quantity and Runoff Quality Controls

10.3.1   Analytical Probabilistic Models for Runoff Quantity Control

10.3.2   Analytical Probabilistic Models for Runoff Quality Control

10.4   Development of PSO Model

10.5   Formulation of the Detention Pond Optimizations

10.5.1   Optimization of Detention Time in Dry Detention Ponds

10.5.2   Optimization of Detention Time in Wet Detention Ponds

10.6   Result of Runoff Quantity Control Performance

10.6.1   Total Suspended Solids (TSS) Dynamic Settling Efficiency

10.6.2   APM Result of Pollution Control Performance of Dry Ponds

10.7   PSO Simulation of Pollution Control Performance of Dry Ponds

10.8   Effect of Pond Depth on Pollution Control Performance of Dry Ponds using APM

10.9   PSO Simulation Results

10.10   Overflow Risk for Dry Ponds

10.11   Pollution Risk for Dry Ponds

10.12   Pollution Control Performance of Dry Ponds across Peninsular Malaysia

10.13   Optimization of Detention Time in Wet Detention Ponds

10.13.1   Runoff Quantity Control Performance of Wet Ponds

10.13.2   Pollution Control Performance of Wet Ponds using APM

10.13.3   APM Result with Active Pool Constant and Permanent Pool Varying

10.13.4   PSO Simulation Result of Pollution Control Performance

IMPOUNDED WATER BODIES—MODELLING AND SIMULATION

This book enhances knowledge on Impounded Water Bodies (IWB) systems of the interested parties. They include academicians, scholars, scientist, researchers, engineers, undergraduate and postgraduate students. Specifically this book is valuable for everyone involved in water, hydrology, environment, civil engineering and other related disciplines. This book emphasized modelling and simulation of IWB particularly; Reservoir and Detention Pond, in relation to the two major hydrological problems; Flood and Water Pollution. The knowledge presented is useful for hydrological systems real phenomenon replication and prediction. This book also provides IWB general overview, in terms of the preliminary and state of the art analysis which may trigger the interest for further research and investigations. The IWB related factors were integrated to provide the quantitative framework, alternative approaches and valuable outcomes that lead to worthy policy establishment. This book covers topic related to nutrient (phosphorus) loadings estimation using the new version of Event-Based Stochastic Model in reservoir systems. The detention pond systems modelling using Analytical Probabilistic Models (APM) and the optimization of detention time using Particle Swarm Optimization (PSO) are elaborated. It is hoped that the book provides useful knowledge in pursuit of the IWB sustainable development.

PREFACE

Impounded Water Bodies—Modelling And Simulation

This book concerned with Modelling and Simulation of Impounded Water Bodies (IWB) particularly; Reservoir and Detention Pond systems. This book mainly discusses the IWB analysis related to the two major hydrological problems; Flood and Water Pollution. IWB is body of water confined within an enclosure or surrounded by watershed boundary. These IWB are developed for multi purposes and functions especially for water quantity control and water quality improvement systems. Water-related domains, such as flood protection, water resources management and water quality amelioration systems face enormous challenges which are emerging from altered global or regional water circulation conditions. Massive public funding have been invested on these hydrologic systems with the eventual ultimate objectives; for human prosperity and well being. Therefore the IWB modelling and simulation studies should optimize the usage of allocated funding, proper planning, design and operation and established cost-effective hydrological systems. This may involve alternatives both for the development of new systems and for the rehabilitation of existing systems.

This IWB modelling and simulation book provides the general overview of the relevant analysis; preliminary and state of the art analysis which may trigger the interest to adventure the related issues further. The case studies discussed provides several alternative methods in the analysis of this hydrological systems. This book evolves from the understanding that some of the traditional methods have deficiencies. The deficiency may be related to the accuracy and precision of the methods in predicting the future system performance under specific input conditions. The deficiency may also be due to the general lack of understanding of the system performance and potential ability to operate in their lifetime under different meteorological scenarios. In this book an alternative approach besides continuous simulation known as Analytical Probabilistic Method were extensively presented.

The first few chapters provide an overview of past and recent developments in water resources and hydrology. The overall and randomly selected past and present hydrological related studies and modelling undertakings were described. The topics provide an overview of state of the art in hydrological modelling and recent trends on modelling hydrological mechanisms in water resources and hydrology. The knowledge and information on obvious challenges and difficulties are beneficial for future studies and predicting the hydrological impacts. The hydrological linkage overviews are useful for future environmental concerns and ensuring the sustainability and availability of fresh water resources.

The flood and urban water pollution problems were discussed in the first few Chapters. There is a need for stormwater management as the total runoff volume increases dramatically nowadays depending on the magnitude of changes to the land surface. These changes cause an increase in the total runoff volume and flow rate across the land surface. The two major types of water pollution; Point and Non-Point Source and their control strategies were generally discussed. The reservoir and detention pond water quantity and quality in terms of the hydrological consideration; surface water pollution and reservoir eutrophication were elaborated.

The basic design concepts demonstrate the fundamental concepts relevant for more advanced modelling and simulation exercise. This topic provides the understanding of the basic concepts thereby the future simulation can be better and meaningfully performed. The Annual Runoff Volume (ARV) or the amount of water flowing on the ground surface during and after rainfall was estimated using the First Principal. The Streamflow Measurement—Velocity-Area Method, Peak Discharge Estimation using the Rational Method, Polynomial Approximation of Intensity-Duration-Frequency (IDF) Curve and Unit Hydrograph including the computation example were presented. These hydrological components pose difficulties and uncertainty in their quantity estimation and thereby impacted water resources projects significantly. The hydrological discharge estimation and basic routing with their relevant data were elaborated and computed. The two major flood routing types; Reservoir Routing and River/Stream Routing were discussed. The peak discharge estimation were estimated using the Time Area Method. The Stage-Discharge Relationship with the graphical output were shown.

The IWB Modelling and Simulation benefits the modellers in terms of the hydrological systems real phenomenon replication and prediction. It incorporate all the knowledge available thereby provides the quantitative framework, alternative approaches and valuable outcome that lead to worthy policy establishment. This IWB hydrological modelling typically involves simulating multi component systems utilizing the stochastic input and output variables. The meteorological data analysis present the statistical analysis of rainfall and the development of probabilistic characteristic representations. The simulation framework needs to be flexible (so that it can accurately represent the systems), transparent (so the models can be easily explained to decision-makers and stakeholders), and able to explicitly represent the uncertainties and stochastic processes inherent in such systems. The Analytical Probabilistic Model (APM) and selected methods in this book is effective in answering these needs.

The analytically derived model, APM was formulated using the probability distribution theory. The meteorological data were described using the probability density distribution depicting their parameters and characteristics. The analysed hydrological variables are mainly rainfall volume, duration, average intensity, and interevent time. These were achieved by combining the flexibility of the general-purpose and highly-graphical probabilistic simulation framework thereby supporting the systems stochastic nature. The potential environmental impacts and risk analyses were discussed to support the strategic planning, and make better future water resource management decisions. These analytical models are reasonably compact, computationally efficient, and easy to use.

The reservoir water quality assessments in terms of the preliminary assessment of nutrients status at Layang Reservoir in Malaysia were discussed. The assessments of related water quality parameters –Temperature, Dissolved Oxygen (DO), pH, Suspended Solids, Limiting Factor, Soil Erodibility Factor, ‘K’ Data were presented. The reservoir modelling and analysis; the phosphorus loadings estimation using the Event-Based Stochastic Model were illustrated. This Event-Based Stochastic Model recognized the stochastic nature of nutrient input and the probabilistic description of phosphorus loadings in terms of their frequency and uncertainty. The runoff discharges estimation using MIKE11 and sediment yield estimation using Modified Universal Soil Loss Equation (MUSLE) were performed.

The detention ponds modelling and analysis emphasizing the development of a variety of runoff quantity control performance parameters in a single catchment urban drainage system were presented. The case studies are presented to provide the reader with the opportunity to better appreciate the utility of the models developed and their practical purposes. Optimization of detention time and the runoff quantity control performance, Total Suspended Solids (TSS) dynamic settling efficiency and APM results of pollution control performance of dry and wet ponds were presented. PSO simulation result of pollution control performance of dry and wet ponds using APM were demonstrated. The study also presented the simulation results for overflow and pollution risk for wet and dry ponds. Reference at the end of each chapter and alphabetical indexing after the last chapter were listed to help the reader with their additional material on the subject matter and their theoretical foundations.

The research documented in this book was funded by a variety of sponsors but principally, by Ministry of Science, Technology & Innovation (MOSTI) Malaysia for the provision of Escience Fund VOT 79394. The support from Universiti Teknologi Malaysia (UTM) is gratefully acknowledged. In addition UTM has provided a wonderful working environment and an excellent library. We thank the Dean of Razak School of Engineering and Advanced Technology, UTM and faculty members for their continuous encouragement which lead to the completion of this book. We thank everyone involved for their direct and indirect support of our work. Especially for our dearest spouses, Associate Professor Dr Azmi Ab Rahman, Mrs Binta Gambo Idris and children for their patience during this busy time. Also the technicians of UTM—Hydraulics and Hydrology laboratory, Faculty of Civil Engineering, UTM for their continuous assistance at the site. Our appreciation to Nusajaya Iskandar Development—Malaysia for the permission to site and the beautiful Nusajaya—Ledang Height detention pond scenery for the cover page.

CHAPTER 1

Introduction

Impounded Water Bodies (IWB) are water confined within an enclosure or surrounded by watershed boundary. The two main types of IWB that impacted the general hydrological systems significantly and being focuses in this book are Reservoirs and Detention Ponds. Flood and Water Pollution are the two major related problems discussed in this book. Reservoirs in this country and elsewhere throughout the world mainly functions as flood control, water supply and water treatment system. They are constantly exposed to disruption risks which may include flooding and drying up risk, eutrophication, sedimentation and stratification. Detention ponds are treatment technologies used for the control and treatment of urban stormwater. These technologies have become popular over the last two decades in Malaysia (DID, 2000). Department of Irrigation and Drainage (DID) in year 2000 introduced detention pond in Urban Stormwater Management Manual for Malaysia (MSMA) as one of the Best Management Practises (BMPs) under storage-oriented approach mainly for its potential as a temporary storage. The stormwater runoff stored could solved flash flood in urban areas and also extended to provide better stormwater quality before releasing into nearby river. In solving drainage problems in urban stormwater management, BMPs included detention pond because they provide both as quantity and quality control of stormwater runoff (Zakaria et al., 2004).

The paradox of water supply shortage problems in Malaysia with an abundant amount of rainfall has certainly affected and damaged the country’s dignity. The incessant water supply shortage problem is really outrageous and needs to be holistically upkeep. The problems which had affected the country’s development and human health need to be solved. The tremendous pressure on the water supply system could be solved either through immediate measures or long term planning. Control of water quantity and quality will be one of the essential steps to solve the problem. Water quantity can be best endured through various strategies such as optimization of water inflow and outflow, reduction of overflow risk and improvements of pond design parameters. Water quality in terms of its pollution need to be continuously upgrade as this will increase the available clean water. Pollution reduces the amount of exploitable water and also increases the water treatment costs. Studies on pollution will be one of the important approaches to safeguard against future water supply crises. Impounded water bodies water quantity and quality degradation must be given attention to ensure sufficient future water supply for the public. Impounded Water Bodies particularly Reservoirs and Detention Ponds in Malaysia are vital entities in ensuring water value and availability are gratified by everyone. Reservoirs and Detention Ponds are constructed to store water for a limited period of time by allowing large inflow but limiting the outflow using the properly designed outlet, weir or small orifice.

1.1   Flood Problems in Malaysia

Flood is a common phenomenon in Malaysian and it re-occurred throughout the country almost every year. The worst period recorded in history is that of December 2006 to January 2007, when the region of South–East Asia was hit by typhoon which affected countries like Philippines, Vietnam, Malaysia, Singapore and Indonesia. In Malaysia, heavy storms occurred which caused series of floods in states like Johor, Malacca, Pahang and Negeri Sembilan (Shafie, 2009). During this period, these Southern Malaysian states, along with Singapore, experienced abnormal rainfall, of up to 350mm within 24 hours, which resulted in massive floods. The flood was considered as the worst in the history of Southern Malaysian region. Urban areas including Batu Pahat, Johor Bahru, Kluang, Kota Tinggi, Mersing, Muar, Pontian and Segamat were flooded. The worst-affected areas in Johor were Segamat and Kota Tinggi, where both towns were totally inaccessible by land after all main roads leading to those towns were flooded. It is estimated that more than 100,000 were evacuated. Excessive rainfall, which exceeds twice the monthly rainfall, occurred in four days. The rainfall recurrence interval was more than 100 years (Shafie, 2009). The rainfall recorded in the city of Johor Bahru on December 19, 2006, amounts to 289mm when the annual rainfall of the city alone is 2400mm. In Singapore, the 24-hour rainfall recorded on December 20 was 366mm, the third highest recorded rainfall in 75 years. Later that week, North Sumatra and Aceh experienced abnormal rainfall which also caused flooding. An estimated 400,000 people were displaced and atleast 118 people dead with 155 people missing (Benjamin et al., 2006; Benjamin et al., 2007).

By the third week of January 2007, Johor was hit by another flood. Singapore and certain parts of Indonesia were also flooded due to the same typhoon. The flooding began when torrential downpours started which caused rivers and dams to overflow. Weather officials described the flooding as the worst in the area in a century. The second wave of the flood, which was larger than the first wave, had almost paralyzed Johor after all eight districts were submerged by the flood. The worst-affected areas caused by the second flood were Batu Pahat and Kluang. Both waves of the flood disaster were considered as the costliest in Malaysian history, with the total cost of RM1.5 billion and at least six people died (Benjamin et al., 2007).

1.2   Water Pollution Problems in Malaysia

Over the last three decades, pollution problems from stormwater runoff have received considerable attention all over the world (Heaney, 1986; Benjamin et al.2006). In Malaysia, Ibrahim (1993) indicated that considerable amount of Point Source (PS) and Non Point Sources (NPS) pollutants are being washed up into the Malaysian rivers. However, not much is documented on NPS pollution from the rural and urban areas. Few studies available include Nazahiyah et al (2007), Al-Mamun (2005) and Lee (2002). Supiah (2003) and Al-Mamun (2005) is one of the earliest to conduct a comprehensive research on non-point source pollution in Malaysia. Al-Mamun (2005) discovered that the median Event Mean Concentration (EMC) for turbidity, Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Biological Oxygen Demand (BOD), COD, Pb, Zn, Cu and Cr from urban residential area were 36 NTU, 47.3, 126.5, 29, 120, 0.0143, 0.3046, 0.0135 and 0.0187 mg/L, respectively. It was also found that pollution from NPS contributed more annual TSS, COD and heavy metal loads than PS in a developed urban residential area.

Stormwater quality and pollution loading of a stream from a residential urban catchment in Malaysia was observed and it was reported that the stream is badly polluted (Nazahiyah et al., 2007). Similarly, Yusop et al (2005) monitored the runoff quality draining from urban catchment which comprises of residential, commercial, industrial and agricultural land–use and reported high concentration of Total Organic Carbon (TOC), Dissolved Organic Carbon (DOC), NH3-N, Fe and colour and presence of heavy metals in trace quantities. The study also concluded that storms of 3 month ARI could capture about 70% of the total annual load of pollutants generated.

Water pollution problems is continuously being addressed by researchers and practiceners in Malaysia. Some of the identified investigations are carried out by Othman, F. (2012); Ujang, Z. (2004) and Khairatunnisa, M. (2011). Othman, F. (2012) studied the point and non point source pollution inflowing into Malaysian rivers. The runoff pollution problem is continuously being adventured in order to obtain better solution and counter measures. Ujang et al. (2004) studied the environmental engineering educational aspects and the related framework for the future importance. The philosophy, approach, criteria and delivery of education are evaluated to help improve the overall environmental status of the developing countries. Khiratunnisa M. (2011) studied quantification and modelling of sediment loading from rural oil palm catchment at Southern Peninsular Malaysia. She outlines several suggestions for sediment control and counter measures.

1.3   Reservoir Problems in Malaysia

Reservoir studies in Malaysia are still lacking, more attention and investigation need to be addressed on this life saver hydrological system. Several of the studies so far are carried out by Hasan Zorkeflee Abu et al. (2012); Ismail Wan Ruslan et al. (2010); Zullyadini, A. Rahaman and Ruslan, Ismail Wan (2006); Hock Hwee Heng and Ching Poon Hii (2013); Zati Sharip and Salmah Zakaria (2008) and Mohd Azraai Kassim et al., (1997).

Hasan Zorkeflee Abu et al. (2012) investigated the hydrological aspect of Bukit Merah reservoir within the Kerian District, Perak State, Malaysia. The reservoir which function as the main water source for irrigation at Perak State irrigation has experienced water shortage and stress. They identified that land-use activities were the contributor of the sedimentation. They applied the Soil and Water Assessment Tool (SWAT) to simulate and quantify the impacts of land-use change in the reservoir watershed. They projected that the land use in the year 2015 and hypothetical land use to represent extensive land-use change in the catchment area. The simulation was carried out based on 17 years of rainfall records and showed that the average water quantity will not be significantly reduced. However they predicted that the ground water storage will decrease and suspended sediment will increase. Ground water decrease and sediment yield increase will intensify the Bukit Merah Reservoir operation problem.

Ismail Wan Ruslan et al. (2010) studied the reservoir sediment input and output of in Bukit Merah reservoir in Perak, Malaysia. They indicated that many issues related to high suspended sediment concentrations, such as reservoir sedimentation, channel and harbour silting suspended sediment loadings has increased significantly in recent decades. The reservoir received inputs from four rivers totaling about 37 600 t year-1. More than 90% of the sediment input (approx. 35 000 t) came from the Sg. Kurau River. The average lake sedimentation rates were 0.36 mm year-1 (1995-2000) and 0.48 mm year-1 (2000-2005). The average suspended sediment concentration in the lake was between 8.6 and 13.5 mg L-1, The reservoir was slightly eutrophic, caused by the impact of sediment and nutrients on the receiving water body.

Zullyadini, A. Rahaman and Ruslan, Ismail Wan (2006) stated that, soil erosion, sediment transport and deterioration of water quality in many river systems in Malaysia have become major concerns in recent years. They investigated the impact of human activities and the role of tropical