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Researchers :
Prof. Dr.
Aminuddin Ab. Ghani <redac02@eng.usm.my>
Prof. Dr. Nor
Azazi Zakaria <redac01@eng.usm.my>
Zorkeflee Abu
Hasan <redac04@eng.usm.my>
Dr. H. Md. Azamathulla <redacazamath@eng.usm.my>
Dr. Lai Sai Hin
Chang Chun Kiat <redac10@eng.usm.my>
Mohd Fazly Yusof <redac07@eng.usm.my>
Project Report:
The project consists of five volumes as stated
below:
Study Objectives:
The study objective is to develop a sand mining planning and management tool
such that DID shall be able to make effective and timely decisions on sand
mining applications and operations based on the following:
i) To asses the current state of river morphology based on on-site data
and determine the capacity of the river to act as natural conveyance to
carry both water and sediment;
ii) To carry out hydraulic/sediment transport modeling study
incorporating both the river and its capacity to sustain sediment extraction
according to the sediment balance within the catchment;
iii)
To formulate a long term solution encompassing sand mining envelope
along the river stretch in terms of both river morphology and
hydraulic/sediment transport modelling;
iv)
To establish Geographical Information System for the study area with
proper data entry and query features so that the system is useful and
practical for planning and managing the morphology of the above said river
system.
Scope of Works:
The scope of works shall include but not to be confined
to the following:
a)
Collection And Interpretation Of Data And Information
b)
Site Investigation And Field Inspection
c)
Engineering Survey And Geotechnical Investigations
d)
River Morphology
e)
Hydraulic Modeling
f)
Planning and Management Tools
g)
Cost Estimate And Implementation Schedule
h)
River Database using Geographical Information System (GIS)
Executive Summary:
USAINS HOLDING Sdn Bhd through River
Engineering and Urban Drainage Research Centre (REDAC) has been appointed by
Jabatan Pengairan dan Saliran Malaysia to carry out
STUDY ON RIVER SAND MINING
CAPACITY IN MALAYSIA beginning 21st
September 2007 for a period of twelve months.
The Final Report presents eight chapters as
follows:
CHAPTER 1 Introduction
Chapter 2 PAST STUDIES
Chapter 3 STUDY AREA
Chapter 4 RIVER MORPHOLOGY
Chapter 5
SEDIMENT TRANSPORT MODELLING
Chapter 6
RIVER SAND MINING ENVELOPE
Chapter 7 RIVER REGISTER
DATABASE
CHAPTER 8 SAND MINING
GUIDELINE
The present study covers three rivers i.e
Sungai Muda, Sungai Langat and Sungai Kurau that have different level of
sand mining activities. Sungai Muda has a long history of sand mining
activity along the upper reach. Sungai Langat recently has been a major
source of sand for construction with the development of Putrajaya. Fewer
activities of sand mining are on-going in Sungai Kurau at the upstream of
Bukit Merah reservoir.
The objectives of the present study include
the assessment of the river morphology, hydrological and sediment transport
modelling and development of river register database. Field works on
selected sites for the three rivers were made to assess the capacity of the
river to convey both water and sediment. Data collection on bed material
was made to characterize the physical characteristics of sediment
responsible for sediment transport that determines the river response in
terms of erosion and deposition. The three rivers clearly have the bed
material size in the sand-gravel ranges based on the collected data in the
present study.
The
replenishment rate as determined from the measured sediment rating curves
for the three rivers show that a steeper curve is obtained for Sungai Langat
as compared to Sungai Muda and Sungai Kurau. Hence, it is expected that
Sungai Langat has a good replenishment rate for the purpose of sand
extraction compared to Sungai Muda and Sungai Kurau.
A detailed sediment transport study at six
sites for each river was conducted to determine the suitability of existing
sediment transport equations for use in the selected sediment transport
models. It was found that Yang and Engelund-Hansen equations are able to
predict the trend of sediment transport for the three rivers.
Hydraulic and sediment transport modeling
study were carried out to determine possible location of deposition along
the three rivers in the present study. The depth and volume of deposition
will in return determine the viability of sand extraction taking into
account the ability of the rivers to replenish the sediment. Three models
were used for this purpose: HEC-RAS, FLUVIAL-12 and SWAT.
Proposals on the minimum level or "redline"
and maximum level for sand extraction are given based on the HEC-RAS
modelling results. It is proposed that the minimum depth of the excavation
or redline must be at 1 m deposition above natural channel thalweg elevation
while the maximum allowable mining depth is 1.5 m. The extraction is allowed
for the whole active channel width after taking into consideration of the
required setback to avoid bank erosion, and buffer zone encroachment.
Allowing the channel wide extraction will increase the volume of the
extraction for a particular site. Hence, few mining sites are allocated for
each river which will minimize the disturbance to river equilibrium and
environment. Based on the sedimentation trend as predicted by HEC-RAS model
and after applying the 1 m redline, it can be concluded that Sungai Langat
is viable for sand extraction purpose while Sungai Kurau should be
prohibited from any sand extraction activity. Since Sungai Muda is being
widened for flood mitigation purpose, it is recommended that deposition
should be allowed to occur first after a major flood before any sand
extraction activity is allowed in the 40-km lower part of the river.
Comparisons with the existing DID guidelines
on sand mining were made based on the modelling results. As a result, a new
guideline on river sand mining management is included in this final report
that emphasizes the impacts of sand mining and several recommendations for a
sustainable sand extraction, including discussions on appropriate extraction
methods and sites adopted from overseas experience. Flood plain mining is
also proposed as an alternative to in stream mining. Also, Geographical
Information System was utilized for the study areas in the development of
river register database.
Finally, individual report for each river is
provided in three separate volumes:
VOLUME I SUNGAI MUDA
VOLUME II SUNGAI LANGAT
VOLUME III SUNGAI KURAU
|
Sediment Rating Curve for Sungai Muda |
Sediment Rating Curve for Sungai Langat |
Sediment Rating Curve for Sungai Kurau |
Comparison of Replenishment Rate for three rivers |
HEC-RAS
Modelling Results for Sungai Kurau
Recommendation: NO SAND MINING ALLOWED |
HEC-RAS
Modelling Results for Sungai Muda
Recommendation: SAND MINING ALLOWED ONLY AFTER A MAJOR FLOOD OCCURS
AT THE COMPLETION OF THE ON-GOING FLOOD MITIGATION PROJECT |
HEC-RAS
Modelling Results for Sungai Langat
Recommendation: SAND MINING ALLOWED |
|
Reach |
Volume of Deposition (tons)
2003 Flood |
Volume of Deposition (m3)
2003 Flood |
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1. CH 109715 - CH 97715
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4,636,000 |
3,004,077 |
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2. CH 85215 - CH 66000
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1,475,000 |
955,784 |
FLUVIAL-12 Modelling Results: Sediment Delivery along Sungai Langat
for different Flood Hydrographs |
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Setback, Redline and Maximum Allowable Mining Depth for In Stream
Mining |
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Floodplain Excavation Pit Geometry |
Download:
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Format |
Title |
Download |
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Berita Harian News on Sand Mining
Activity - Jawatankuasa diwujud mantapkan mekanisme pantau aktiviti
ambil pasir sungai |
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