Bachelor Thesis - Sedimentation Reduction and Check Dam Design in the Cilalawi River (GJVos)_send

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Bachelor Thesis

23 January 2012

Institutions

University of Twente

Faculty of Engineering Technology

Civil Engineering

Enschede

The Netherlands

Padjadjaran University

Faculty of Agricultural Industries Technology

Institute of Ecology

Bandung

Indonesia

Supervisors

Dr. Ir. H. Wagiono

Faculty of Agricultural Industries Technology

Institute of Ecology

Padjadjaran University

Dr. K.M. Wijnberg


Department of Water Engineering & Management

Civil Engineering


Author

Gerben Jan Vos

[email protected]



Bachelor Civil Engineering

i

Foreword

This is the Bachelor Thesis of Gerben Jan Vos within the educational institutions of

Padjadjaran University in Bandung, Indonesia, and University of Twente in Enschede, The

Netherlands. The period for this project is ten weeks and the residence was in Jatinangor,

Sumedang, Indonesia, where the second location of the Padjadjaran University is situated.

The reason for this report is a problem of erosion and sedimentation in and near to

the Cilalawi River in West Java, Indonesia, which is resulting in water storage reduction of

the reservoir Waduk Jatiluhur downstream. This report treats the progress in achieving the

goal including the complete check dam design to counter sediment transport problem.

I owe the completion of this report to several persons and companies. First of all, I

would like to thank Dr. H. Wagiono of the Padjadjaran University and Dr. K.M. Wijnberg of

the University of Twente for guiding me as supervisors through the project. In special, a word

of thanks to Ir. K.T. Veenvliet of the University of Twente. He provided guidance in the design

phase and in finishing the report. Secondly, I thank my father, Ir. M.J. Vos, for giving me

supporting expertise and encouragement. Thirdly, Laura Septy Ferlany and Fattah Tamtanus

were important companions in the bureaucratic data collection. They were my counterpart

students who helped me inside and outside the project during the total period. Furthermore,

several people in the community of the faculty of Agricultural Industries Technology were

crucially helpful. Dr. M. Muheamin as president welcomed me to his faculty and made my

stay comfortable, while Ir. MT. T. Pujianto as vice-president completed a variety of formal

letters to obtain data from participating companies and was also responsible for the

successful stay. The last person of the faculty I am grateful for, for guiding me in AutoCAD, is

Ir. M. Saukat. Finally, I want to thank all the data providing companies, especially the Water

Research Center in Bandung, and the person who checked the language, spelling and

grammar of the complete report, Drs. A.E. Reinders of the The Hague University.

ii

Abstract

An overdose of sediment from the Cilalawi River is going into the reservoir Waduk Jatiluhur.

This is resulting in the problem of reservoir capacity reduction. With water still coming from

different rivers, the future will be inundation. In this matter the recommendation for this

problem is check dam(s) and changing land use, stated by the local government, Perum

Jasa Terta II (PJT II). These solutions can both reduce sediment transport in the river by

respectively decreasing flow velocities and reduction in erodibility.

The Cilalawi River and reservoir Waduk Jatiluhur are located in the province of

Purwakarta, West Java, Indonesia. Cultivation, forest and buildings surround this river.

Residents in this area are using the river for waste disposal, private fishing, washing and

recreation, while chemicals and excreta heavily pollute it. What is more, the PJT II manages

the policy for rivers in West Java region. On the contrary, there is currently no policy

concerning the Cilalawi River, although, recommendation has been written for the described

problem.

Therefore, the goal is to use the design of a functional check dam to estimate the

impact of the civil structure on erosion and sedimentation in the watershed. Land use

changing is no option, because of the large surface area to treat, the additional high

expenses and the essential sawah existence with high erodibility.

The research questions to the theme and to achieve the goal are:

1. Which characteristics of the Cilalawi River and watershed are responsible for the

sedimentation and erosion?

2. What would be the design of the functional check dam for the Cilalawi River?

a) What are the requirements for the new check dam?

b) What will be the time horizon of the check dam till its expiration?

c) What does the designed check dam look like in the phase of preliminary design?

The check dam in this project is an object, which will catch moving sediment in the upstream

to hold it in the original catchment area. For the model of the dam the characteristics of land

use, river conditions, climate and preconditions have been taken into account. Prior to the

check dam design data collection was needed to derive, for example, discharges, elevations

and precipitation.

Study of the check dam resulted in a definition of the structure, stated as:

'A check dam is a civil structure that is built in an active channel, perpendicular to both river banks, to

achieve erosion reduction in the river and catch sediment upstream by decreasing flow velocities.'

After the study area description the requirements are collected followed by potential locations

and dam alternatives. Environmental requirements demand a dam in a straight upstream

section with the narrowest profile. Moreover, the design prevents inundation upstream and

erosion in the downstream, meanwhile the performance requirements of the check dam

claim: 25 year peak discharge, ability to treat a watershed of 72 km2 or smaller, the longest

lifetime, maximum height, conduction on spillway, constructed against damaging obstacles

and a forced hydraulic jump. The last requirements are technical and physical, which ask for:

downstream dam slope of 20-30%, upstream dam slope of 45% or more, dam positioned

perpendicular to the flow direction and river banks, and minimum maintenance required.

Chosen is for an impervious concrete check dam at the location of Babakansari East.

The location is chosen from four vantages in the upstream with mainly the environmental

requirements, while the concrete check dam is selected by the performance requirements.

Beside the impervious dams are the temporary and regular dams, which are both limited by

iii

lifetime. The regular dams also need more maintenance and are less firm as impervious

check dams. Within the impervious dams the concrete dam is the only without height limit;

the used dam in this project.

The created sub-watershed is besides the sediment transport model, modeled on

land use soil to get insight into the erodibility process. The land uses with the average rainfall

in the Rational Formula are providing 300 thousand m3/year of sediment going into the river.

Consequently, the sediment of the river can be divided into three types: bed load, suspended

load and wash load. The sediment transport is modeled by the formulas of Meyer-Peter &

Müller (bed load) and Engelund & Hansen (bed load and suspended load) with the result of

respectively 74.2 thousand m3/year and 88.9 thousand m3/year. The high uncertainty in the

used parameters and outcomes are causing difficulty in the conclusion that there are high

amounts of wash load. Compared with the amount of sediment by the Rational Formula, it

can be stated that almost 100% of the soil is coming from land use.

According to the PJT II, there is capacity reduction in the reservoir Waduk Jatiluhur of

274 million m3 in 10 years. This amount results eventually in 13.6 million m3/year of sediment

transport from the treated Cilalawi River watershed. This amount is compared with a

reservoir called Sermo in East Java, Indonesia. The difference in sediment settlement of the

Cilalawi River in the reservoir is assumed to be a factor 10 less, resulting in 1.36 million

m3/year. Consequently, the calculated sediment transport of 88.9 thousand m3/year could

become closer to reality with this fact and all the parameter uncertainties.

The check dam design is the next phase, knowing the river profile and the sediment

transport. The height of the dam is determined by the height of the river profile and maximum

discharge of 77.7 m3/s. As a consequence, the dam will be 2.1 m high and has a sediment

storage capacity of 3000 m3. The average discharge of 5.54 m3/s shows 12 days of

expiration time and less than 1 with all the uncertainty. This leads to the advice of multiple

check dams or dredging for a deeper channel. Multiple check dams will each treat a smaller

catchment and will have larger expiration time. Research in this option is required starting in

the upper reaches. in addition, dredging is expensive and the impact is smaller as result of a

limited water depth. In case of subsequent check dams the expiration time is required to be

the same for every check dam and long enough so dredging can be planned. Overall, after

the dividing of the complete area and the treated surface area sections, the several river

properties and sediment transport need to be analyzed over again to achieve a coherent

design.

The check dam design in this report has the height of 2.1 m with a semicircular

spillway containing a radius of 1.79 m. The round cross-section of layout is for reason that

the stream needs to be guided into the downstream to prevent unwanted forces. Between the

semicircle spillway and the concrete plate the dam has two small dam slopes. Furthermore,

the two wings parallel to the stream are designed with 0.30 m thickness directed towards the

bottom of the dam and they have a maximum height of 5.15 m. The sidewalls, attached to

the wings, are as giant pillars at the boundaries of the spillway narrowing the influx of the

stream. They have the same thickness as the spillway. The lowest level of the check dam is

the apron in case of a soil underground. The apron length for the hydraulic jump and

incoming turbulent stream is 7 m. The thickness of this plate is also 0.30 m against damaging

stones and trees in the stream. The end wall of 0.5 m height is a small dam with the same

dam slopes as the actual check dam, forcing a hydraulic jump. After the end wall the

concrete plate of the apron continues with 5 m. The collapse bed of large diameter stones

continues after the concrete plate until the other side of a bridge in the downstream. This is

preventing erosion, which can cause the bridge falling apart.

List of Contents

1 Introduction ...................................................................................................................................................... 1

2 Methodology .................................................................................................................................................... 2

3 Problem Analysis ............................................................................................................................................ 4

3.1 Watershed Characteristics ............................................................................................................................. 4

3.2 Problem Definition .......................................................................................................................................... 4

3.3 Recommendation ........................................................................................................................................... 5

3.4 Goal Definition ................................................................................................................................................ 5

3.5 Check Dam Definition ..................................................................................................................................... 6

4 Study Area Description ................................................................................................................................... 7

4.1 Study Area ...................................................................................................................................................... 7

4.2 River Use ....................................................................................................................................................... 8

4.3 Policy .............................................................................................................................................................. 8

4.4 Site Investigation ............................................................................................................................................ 8

4.5 River Course ................................................................................................................................................ 10

4.6 Elevation ...................................................................................................................................................... 10

4.7 Land Use ...................................................................................................................................................... 11

4.8 Waduk Jatiluhur ............................................................................................................................................ 11

5 Requirements ................................................................................................................................................ 12

6 Location .......................................................................................................................................................... 14

7 Sediment ........................................................................................................................................................ 16

7.1 Classification ................................................................................................................................................ 16

7.2 Rational Formula .......................................................................................................................................... 17

8 River Model .................................................................................................................................................... 18

8.1 River Profile .................................................................................................................................................. 18

8.2 Sediment Transport ...................................................................................................................................... 18

9 Check Dam Design ........................................................................................................................................ 20

9.1 Check Dam Alternatives ............................................................................................................................... 20

9.2 Model ........................................................................................................................................................... 21

9.3 Dimensions .................................................................................................................................................. 23

9.4 Underseepage and Outflanking ................................................................................................................... 25

9.5 Stability ......................................................................................................................................................... 25

10 Discussion ................................................................................................................................................... 26

10.1 Parameter Uncertainty ............................................................................................................................... 26

10.2 Sedimentation Inconsistency ..................................................................................................................... 26

10.3 Design Discharge ...................................................................................................................................... 27

10.4 Verification ................................................................................................................................................. 27

11 Conclusion ................................................................................................................................................... 28

12 References .................................................................................................................................................. 30

13 Appendices .................................................................................................................................................. 32

Appendix A Flow Chart ........................................................................................................................................... 32

Appendix B List of Data .......................................................................................................................................... 33

Appendix C Interview PJT II Purwakarta ................................................................................................................ 34

Appendix D Catchment Area of Cilalawi River ........................................................................................................ 35

Appendix E Elevation Map Catchment Area of Cilalawi River ................................................................................ 37

Appendix F Land Use Map Catchment Area of Cilalawi River ................................................................................ 40

Appendix G Requirement Validation ....................................................................................................................... 42

Appendix H Location Check Dam ........................................................................................................................... 43

Appendix I Soil Classification .................................................................................................................................. 45

Appendix J Captured Catchment Area ................................................................................................................... 48

Appendix K Precipitation Cisomang ....................................................................................................................... 50

Appendix L Land Runoff Formula ........................................................................................................................... 60

Appendix M Parameter List .................................................................................................................................... 61

Appendix N River Profile ......................................................................................................................................... 62

Appendix O Flow Velocity ....................................................................................................................................... 64

Appendix P Discharges .......................................................................................................................................... 66

Appendix Q Flow Type ........................................................................................................................................... 76

Appendix R Sediment Motion ................................................................................................................................. 78

Appendix S Expiration Time .................................................................................................................................... 80

Appendix T Apron Length ....................................................................................................................................... 81

Appendix U Grain Size Velocities ........................................................................................................................... 83

Appendix V Stability ................................................................................................................................................ 84

Appendix W Technical Drawings ............................................................................................................................ 85

1

1 Introduction

This report is about a project in River Engineering concerning the Cilalawi River in West Java,

Indonesia. The environment of the river is using and affecting the water. So, nature (sawah,

vegetables, fruit, shrubs and forest) feeds itself with water and releases sediment going into

the stream. The residents in the same area provide pollution and are using the river for

fishery. Meanwhile, the river is influenced by slopes differences and meandering along the

complete course. For this river, the government, Perum Jasa Tirta II (PJT II), rules policy and

provides essential information.

The problem is an overdose of sediment going into the reservoir Waduk Jatiluhur,

which causes reduction in water storage capacity of 274 million m3 in 10 years, stated by

research in watermanagement by PJT II. Recommendation of the government is to decrease

deposition of sediment in the reservoir by generating (a) check dam(s). Changes in land use

to control erodibility, as solution, is almost impossible with the residents and is expensive.

Therefore, the solution is to be found in a functional check dam design.

The objective of this project is to get insight in the design of a functional check dam

as solution for the sediment transport problem. The designed check dam catches the

sediment in the upstream resulting in reduction of sediment for downstream. The design will

be made using knowledge about sediment transport, river conditions, requirements and

check dam alternatives resulting in a functional dam in preliminary drafts. The preliminary

report [Vos, 2011] was the preparation for this project.

There are research questions to be answered for achieving the objective. The first

question is about the processes in and around the river that leads to the decision of

designing a check dam. This will be answered in the early project stages. The second

question that is divided into three sub-questions gives globally the outcome of the project and

the process of the functional check dam design in the Cilalawi River.



It is due to site investigation and knowledge gathered from various studies, that the

morphology conditions in the river can be approached. There is knowledge about land use,

elevation, discharges and precipitation. Furthermore, surveys in analyzing the river and the

modeling of the sediment transport provide answers to this question.


a) What are the requirements for the check dam?



The requirements for the check dam come from literature and experts. The designed

dimensions, the sediment transport model, the found data on erosion and sediment rates can

lead to estimations about the expiration time. Lastly, the check dam will be visualized in

preliminary design.

The report is composed of a problem and a location analysis till the complete

substantiated civil structure. In Chapter 2 the method and the way of tackling the problem is

considered. After the methodology, the definition of the problem is given in Chapter 3.

Chapter 4 is dedicated to the analysis of the river and its location followed by the

requirements mentioned in Chapter 5. The exact location is given in Chapter 6, which is

followed by Chapter 7 about river sediment. In Chapter 8 and 9 the model of the river and the

complete design of the check dam is developed. Chapter 10 treats the discussion part and

this report will end with the concluding Chapter 11.

2

2 Methodology

The visualization of the approach of the project is given in Appendix A. The basis is the

preliminary report, which contains the global planning and background information of this

project. The general approach is: Preliminary report (I), Problem analysis & definition (II),

Project description (III), Location Determination (IV), River Modeling (V) and Check Dam (VI).

Goal Description

The problem of an overdose of sediment going into the reservoir must be interrupted by a

check dam design. The study makes clear what the impact is of a check dam and what the

sequential proceedings are to treat the sediment transport.

Preliminary Phases

Prior to the data collection and mathematical model is the preliminary report, the problem

analysis & definition and the project description.

The preliminary report consists of the literature study and the global plan. Literature is

coming from the library of the University of Twente and books of the study Civil Engineering

in the mentioned university and the Delft University of Technology. The library contains the

search engine Scopus for the archive and database. Search terms in different combinations

are mainly: check dam, sedimentation, erosion, analysis, tropical, rivers, West Java,

Indonesia, Asia. The obtained knowledge was used to generate the global work plan, which

is parallel to this report, and to provide background information on the subject. For example,

there is spoken about the climate in Indonesia, the function of a check dam and the

morphology.

Communication with the supervisor and the government leaded to the problem

definition stated by the regional government. Coupled to this definition is the formulated

objective.

When the problem was known the location was analyzed by visit and data from

different companies. The study area is a description of the river and his environment by

mentioning the location, the function, the policy, the course and the reservoir. Furthermore, it

contains the analysis on the elevation and the land uses obtained by Water Research Center

in Bandung, West Java, Indonesia.

Data Collection

In the preparation of the data collection there is generated: one data list (Appendix B) for all

participant organizations and an interview (Appendix C) for PJT II. The several information

providers will be mentioned. The organizations, which were supporting the data collection,

are in sequence of visit:

1. Pusat Penelitian Sumber Daya Alam - Lembaga Penelitian dan Pengabdian kepada Masyarakat

(PPSDAL - LPPM)

Library of Padjadjaran University Institute of Ecology

2. Center of Information Scientific Resources and Library (CISRAL)

Library of Padjadjaran University Diparti Ukur

3. Pusat Penelitian Air (PUSAIR)

Water Research Center (Bandung)

4. Balai Besar Wilayah Sungai (BBWS)

Central River Region

5. Dinas Pengelolaan Sumber Daya Air (PSDA)

Water Resource Management and Maintenance

6. Perum Jasa Tirta II Purwakarta (PJT II Purwakarta)

Water Management Region Puwakarta

3

The two libraries of the Padjadjaran University in Bandung supported the catchment area

data and map. Consequently, Water Research Center (Bandung) showed modeled

weirs/check dams in the hydraulic laboratory. They were able to provide a land use map, a

elevation map, discharges for 10 years collected by PJT II with a checkpoint and precipitation

data of the Cisomang River. The Cisomang River is the closest river, adjacent above the

upper reaches of the Cilalawi River. BBWS also gave discharges, but the most important was

the reference to the PSDA. The PSDA have the same discharge data with maxima and

minima. The last organization is the government department PJT II, which provided the

problem description and the confirmation of the goal for this report. This is summarized in the

table 1.

Data Year(s) Organization Purpose

Problem 2009 PJT II Purwakarta Problem Definition

Catchment Area Map 1978 and 2011 PPSDAL - LPPM

and PUSAIR

Study Area

Land Use Map 2011 PUSAIR Study Area

Rational Formula

Precipitation 2001-2009 PJT II Purwakarta Rational Formula

Elevation Map 2011 PUSAIR Study Area

Sediment Transport

Discharges 2000-2009 (excl.

2003 and 2004)

BBWS and PSDA Sediment Transport

Check Dam Design Table 1 External Data Collection

Survey

During the data collection it became clear that not all the data were known. Hence, survey

was performed to obtain the missing river profile, essential flow velocities and soil properties.

Before the modeling the check dam location has been determined by the

requirements and the observation of the complete river. An unusable river profile

downstream was given by the PSDA. Owing to this, the river profile is measured at the

location of the check dam in order to obtain the schematic profile for the sediment transport

formulas.

During the same survey the current meter measured flow velocities, because only

discharges were given and assumptions had to be made about the Chézy coefficient.

The soil sample was the last part for the sediment movement model. Residents filled

a bottle with sediment 500 m downstream of the check dam location. The sediment would

show the transported soil through the measured river profile. That sample was analyzed by

soil classification.

Modeling

First of all, the rational formula for land surface runoff is used with the precipitation data and

land use map. Secondly, the model of the sediment transport consists of; current conditions

of the flow, estimation of plausible sediment movement, Chézy coefficient calculations and

the use of Meyer-Peter & Müller, and Engelund & Hansen with elevation map and discharges.

This complete model is based on experimental formulas, which is resulting in uncertainty in

the results.

The model is followed by the determination of the check dam dimensions (dam slopes,

spillway, apron, sidewalls and wings). This is possible by knowing the maximum discharge

and water level. The final step is the expiration time in consideration of the thrust curve.

Additional, seepage under and around the dam, the stability of the dam due to water

pressures, and the shear forces have been taken in consideration.

4

3 Problem Analysis

This section is reserved for the extension of the problem description and goal mentioned in

the introduction. Watershed characteristics will support and clarify the problem. After the

problem definition the goal and check dam definition will be given in order to get a clear view

of the purpose. The problem will be made concrete and handled after this section by

research on the location, the river conditions and the dam solution.

3.1 Watershed Characteristics

Combinations of land uses, slopes, erodibility and the influences of the river will give view on

the causes of the problem. More about this subjects can be found in Chapters 4 and 6.

The land uses, sawah, gardens, vegetables and fruit belong to land type cultivation.

Simultaneously, the buildings with their margins belong to the barren and the shrubs to the

forest type of land. According to Singh and Khera [2008], the erodibility of the cultivation and

barren has the highest responsible for less retaining of land. Forest has the lowest erosion

rate and furthermore, there is no grassland in the treated catchment area (table 2).

Land Type Land Uses Percentage (%) Erosion Ratio

Barren Buildings & Houses 15 0.97

Cultivated Sawah, Gardens, Vegetables & Fruit 70 0.84

Grassland - - 0.74

Forest Shrubs & Forest 15 0.63 Table 2 Land Type and Erodibility combined with Land Use and Percentage by Singh and Khera [2008]

The map with explanation table of 1978 in Appendix D shows that there are steeper slopes in

the north and the south areas of the catchment area. Steeper slopes result in higher runoffs.

These runoffs erode the soil especially from cultivated or barren grounds.

The north and south areas are mainly occupied by sawah. This is the main cause for

the fact of already present sediment in the upstream of the main river. So, the steeper slopes

with the higher erosion rate on the sawah land result in large amounts of sediment in the river.

The gradients in Appendix E will be assumed as representative for the river slopes.

Due to high flow velocities in the upper reaches, sediment and suspended clay is inevitably

going downstream. This means that large amounts of sediment are coming from the upper

reaches. So, it can be said that most of the sediment will come from the upper reaches.

3.2 Problem Definition

The problem of the Cilalawi River is not in sedimentation in the river with the sequence

inundation as mentioned in the preliminary report. There seems to be enough space in the

river for all kind of discharges. However, sedimentation is a problem for downstream, the

reservoir Waduk Jatiluhur. PJT II [2009] quoted:

"The water main entrance (Citarum) of the Waduk Cirata reservoir contains a relatively small

sediment concentration, while water enters from watershed Cilalawi River and Cisomang

River carry relatively high concentrations of sediment." (PJT II, 2009: 16)

The outflow of the Citarum in the Waduk Cirata reservoir, before heading to Waduk Jatiluhur

(Ir.H.Djuanda), causes less sediment transport, unlike the Cilalawi River. This is due to the

intervention of the Waduk Cirata. The river is, in this respect, continuous down to the outflow.

5

"The estuary in alignment with the Cilalawi River outlet shows that the surface of the

reservoir base deposition is ± 10-15 meters in 2009 compared with the results of

implementation in 2000." (PJT II, 2009: 17)

"The sedimentation concentration in watershed Cilalawi River is more significant compared

with Cisomang River (and outlet reservoirs Cirata). The basic contour map of 2009 around

the location of the outlet water reservoir dam and the estuary of the Cisomang River shows

basic deposition ± 5 meters of the reservoir surface compared with the results of the

implementation of the underwater contour map in 2000." (PJT II, 2009: 19)

The bed of the reservoir base rose between 10 and 15 meters in 10 years within 15.5 km2 of

bed surface, while the Cisomang River provides 5 meters of deposition in the same period

and surface.

"The Waduk Jatiluhur current storage capacity is 2173.13 million m3 with the details of an

effective storage of 2120.34 million m3 and dead storage of 52.79 million m3. There has been

a reduction in storage capacity of ± 274 million m3 in the period of nearly 10 years. Reservoir

capacity at this time is ± 73% of capacity design." (PJT II, 2009: 20)

Cilalawi River and Cisomang River are both responsible for the reduction in the storage

capacity. The difference is that the Cilalawi River provides approximately 70% with 12.5

meters rising and the Cisomang River 30% with 5 meters measured rising of the bed surface.

The rivers are responsible for the numbers in table 3.

River Bed Rising (m) Percentage (%) Quantity (m3/10 years)

Cisomang 5 30% 82,000,000

Cilalawi 12.5 70% 192,000,000 Table 3 Sediment Quantities of Cisomang and Cilalawi River

Therefore, the problem is defined as an overdose of sediment of the Cilalawi River

transported into the reservoir Waduk Jatiluhur, assumed to be 192 million m3/10 years,

resulting in reduction of the water storage capacity, which will ultimately result in inundation.

3.3 Recommendation

For the solution of the problem, PJT II [2009] also quoted:

"It is necessary to do land management and conservation in the catchment area in

watershed Cilalawi and Cisomang to reduce the rate of sedimentation." (PJT II, 2009: 19)

According to the PJT II land management is focusing on changing land use by retaining the

sediment and conservation in the catchment area must be provided by building a check dam

to catch the sediment in the river, which taken by the water flow, stated by Mr. A. Mardiyono

head of PJT II.

3.4 Goal Definition

It is of great importance that the reservoir Waduk Jatiluhur retains enough capacity to store

the water quantities of Cilalawi and Citarum. The goal of this project is to get insight in

countering the sedimentation in the Waduk Jatiluhur by designing a check dam in the

Cilalawi River.

The check dam will catch transported sediment in the upstream. The result is that soil

is kept in the original catchment area. The characteristics of land use, river conditions,

6

climate and requirements are taken into account for the model of the sediment and the check

dam.

The final result will be a technical design of the check dam in the preliminary drafts

with time horizon of expiration as a functional design. To obtain this result there are two

research question generated.







Firstly, the area need to be investigated and the size of the sedimentation problem. This data

and information will be used to match the check dam solution. Secondly and lastly, the

design of the dam will give clarity in the functionality of the civil structure meeting the

requirements.

3.5 Check Dam Definition

Check dams belong to the category of

dams with the function of catching

sediment. The civil structure is the same

as the weir, only this last one needs to

increase water level for the intake of

irrigation water (pers. comm. Dr. Slemat,

head of the Water Research Center in

Bandung). The dams reduce the effective

slope of the channel. Decreasing the

velocity of flowing water allows sediment to

settle with simultaneous reduction of

erosion (figure 1). Check dams can be

permanent or temporary barriers

constructed from a variety of materials, for

example: rocks, logs and concrete

[California Stormwater BMP Handbook,

2003]. The definition will be:

'A check dam is a civil structure that is built in an active channel, perpendicular to both river banks, to

achieve erosion reduction in the river and catch sediment upstream by decreasing flow velocities.'

Figure 1 Construction of Check Dam by Dindigul District

7

4 Study Area Description

In the previous section the region is not thoroughly discussed. This section speaks about the

characteristics of the Cilalawi River as noted in the research question 1. It also provides data

for the sediment transport, which makes estimations possible of check dam performance

possible. First of all, the study area, the river use and the policy are treated. Secondly, the

observations made during the site investigation will be considered. Thirdly, addressed are

the river course and the characteristics in land use and elevation. Finally, the report will

describe the Waduk Jatiluhur as end station of the Cilalawi River.

4.1 Study Area

The river section that is treated is

located between Palinggihan and

Cibinong (figure 2). Two small

horizontal lines in black and red give

the borders of the main river. The flow

direction of river is from south towards

north in the province of Purwakarta.

The Waduk Jatiluhur is the outlet of

the river. Water of the rivers Cilalawi

River and the Citarum supply this

reservoir.

Northeast of the village Plered

2 the main Cilalawi River begins after

the confluence of two smaller rivers

with large sub-watersheds. Further

downstream are two main roads (solid

line) and one railway (dash) crossing

the river.

The main river has the

distance, as the crow flies, of 6 km

with a total length of 9.5 km. The

catchment area is calculated at 72.06

km2 (see Appendices E and F); these

appendices contain the watershed

with elevation and land use. At the end

of this section the whole elevation and

land use analysis is done. This is part

of the properties of the watershed.

The rainfall pattern in this

watershed can be divided into two

periods: 3 months of drought and the

same period for heavy rainfall.

Between these periods there is the

transitional period. As a matter of fact,

the dry season is from December till

March and the wet season is from

June till September. With an annual precipitation between 2500 and the 3000 mm, the

location belongs to the wet climate.

[Aqil et al., 2006: 370] Figure 2 Cilalawi River Map

8

4.2 River Use

Only residents are directly using the river. Industries are using the river indirectly by having

pump systems in the Waduk Jatiluhur. Commercial fishery, navigation, recreation purposes

for visitors/foreigners are not possible owing to the hygiene. The river is too narrow and

shallow for navigation and has too high flow velocities. Also at the mouth of the river in the

reservoir no fishery will be found, what would be normal in case of clean water.

Residents are using the river for waste disposal, private fishing (for the fish species

Lele and Nila), washing and recreation. Besides, raw materials for the construction of roads

are taken from the riverbed. The residents! excreta and waste disposal leave heavy

chemicals and cause illnesses in the water. Drinking water supply from the river is not an

option.

On the riverside there are still many sawah to be found, because of the high activity

agriculture in whole Indonesia. The sawah on the lowest level are mainly using water from

the river. The higher levels are supplemented by water out of rainfall.

4.3 Policy

Persusahaan Umum (PERUM) Jasa Tirta II (PJT II) is one of the State-owned Enterprises,

which has permission by the government to maintain all the river aspects including

infrastructure of Water Resources and water quality for 74 rivers in West Java. [Indonesia

Infrastructure Initiative, 2010] The major concern of the PJT II is the Citarum, which is

crossing almost whole West Java. No waterpolicy exists for the Cilalawi River, because it is a

small river compared to the Citarum (pers. comm. Mr. A. Mardiyono, head of PJT II). There is

no current policy, but there are plans for in the future mentioned in the second chapter.

4.4 Site Investigation

The first visit of the river with a view to the location

analysis contained a total of three points to observe the

situation. The purpose of this visit was to be able to

describe the circumstances. The locations were:

1. Bridge at Anjun North

2. Left of Palinggihan

3. Cilalawi River mouth

It became clear by having interviews with residents what

the conditions of the river are. Yellow/brown water (figure

3) already indicated large amounts of sediment coming

from the upper reaches of the river. The cause of the

problem (sediment transport) is visualized in figure 2

along the river as a red line. At the end of the river in the

Waduk Jatiluhur the problem (deposition) has been

reflected in the red-hatched area. The second chapter is

dedicated to identifying the problem.

In figure 4 the inflow of the Cilalawi River is

shown at the level of Cibinong. At this section the river is

a channel in the sandy-clay land.

In figure 5 a small part of Jatiluhur is shown,

which is directly adjacent to the river mouth. Even the fishing boats of the reservoir do not

come in this area, because of the small water depth.

Figure 3 Cilalawi River with (Railway)

Bridge at Anjun North

9

Figure 4 Inflow of Cilalawi River in Waduk Jatiluhur (Panorama)

Figure 5 Cilalawi River Deposition in Waduk Jatiluhur (Panorama)

The river contains no civil structures and the water carrying capacity of the river is sufficient,

because there was not any inundation during maximum discharge in 2001, according to the

PJT II discharge data.

A closer look near the river in the field and from the map shows a few characteristics.

The river is narrowing and broadening over the total river course. The river width varies

between 5 m and 16 m.

Due to changing river widths and sediment banks there are deep and shallow parts in

the river, approximately 0.5 until 1.5 m in the transition months of June and May. A few

sandbanks with heavy rocks are splitting the river into two branches. In short, there is no

recent problem within peak flow flood waves for flooding of cultivated land.

The soil properties of the riverbed differ from upstream to downstream. In the

upstream there is small grain while in the downstream grain diameter increases to gravel and

rocks. The clay substances suspended in the stream find their origin above the main Cilalawi

River. Close to the reservoir there are large rocks, which can be obstacles in the stream.

In the river is no vegetation due to the heavy pollution, which captures the sunlight.

From the upstream to downstream there are a lot of sawah irrigated with the river water. The

most cultivation is located only upstream. Downstream of the river the surface area in use is

by irrigation reducing towards the reservoir.

There are no thresholds in this river. Only the heavy rock area in the downstream

seems to have great elevation changes. There are no natural barriers or waterfalls. The main

subsoil of the bed of the river area does consist of rock, sand and clay. As mentioned earlier

the heavy rocks are deposited in the downstream and along the river in banks. This material

needs high flow forces to transport them, concluding that their origin is the main river course.

10

Furthermore, Appendix F shows volcanic geomorphology along the complete river. Volcanic

deposits are always containing large rocks.

4.5 River Course

The Cilalawi River course exhibits familiar patterns of the idealized river [Ribberink, 2007]. It

can be divided into three global sections:

1. Upper reaches (mountain area and origin of the river)

2. Middle reaches (between origin and river mouth)

3. Lower reaches (inflow of river in sea or reservoir and end of the river)

These reaches characterize, in ideal conditions, high flow velocities in the upper reaches,

lower flow velocities in the middle reaches and transition in the lower reaches. The main river

possesses the middle and lower reaches.

The river mainly shows meandering and braiding in lesser extent along the whole

main river. Moreover, there are sandbars and channels in the middle reaches, and in the

lower reaches a small delta is formed where the river enters the reservoir. This delta is the

last stage where the flow velocities will be not significant and the sedimentation base is

formed.

More about the different branches of the main river can be found in two appendices B

and C, which are mentioned in the next paragraphs.

4.6 Elevation

The elevation fluctuates from the origin of

the smaller river in the upper reaches to the

end (figure 6). In Appendix E the elevation

map is divided into four sections, which

includes one section outside the area of

investigation, the upper reaches.

The upper reaches have the highest

elevation and differences in elevation. This

is a logical result of the hills in these

sections. After the average gradient in the

upper reaches come the flatter reaches in

respectively the middle reaches, the

downstream, and the upstream. The

downstream slopes decrease to almost zero

in gradient where the river approaches the

reservoir (table 4). The elevation map in the

appendix shows high elevation differences

before the delta, while in the upstream the

gradient is the smallest. Consequently, the

meandering length is the factor causing

reduction in slopes.

River Section Gradient (%)

Upper Reaches 1.2

Upstream !"#

Middle Reaches $"%

Downstream &"$ Table 4 River Section with Slope

Figure 6 Cilalawi River Catchment Area

11

4.7 Land Use

There seems to be inhomogeneous distribution of land use in the catchment area (table 5).

With a close look there are the differences of surface area of each land use for each section.

In Appendix F the land use in the catchment area is analyzed. These numbers are used in

the runoff on land in Chapter 7.

Indonesia is characterized by a high population and cultivation rate With small houses,

the population is no dominant factor in the land use distribution. Apart from this, at the

borders of many cultivation area, shrubs and forest are situated. The large amount of sawah,

vegetable and fruit land have, for technical reasons, more shrubs. The reason is that the

shrubs are making the land slopes stable. To be more precise, the vegetation supplies

retaining borders around all the cultivation land use during high rainfall periods with heavy

runoffs.

Land Use Percentage (%)

Sawah 35

Vegetables and fruit 20

Buildings & Houses 15

Gardens 15

Shrubs 10

Forest 5 Table 5 Land Use and Percentages of Catchment Area by Water Research Center (Bandung, Indonesia)

4.8 Waduk Jatiluhur

The reservoir Waduk Jatiluhur, approximately

80 km2 [Tim Pemeruman Waduk Ir. H.

Djuanda, 2009], is the third reservoir in the

Citarum watershed. The reservoir separates

the downstream (figure 7) by dam

construction from Citarum upstream, Cilalawi

River and other smaller rivers.

Reservoir Waduk Cirata and reservoir

Waduk Saguling are in the upstream of the

Waduk Jatiluhur. After the three reservoirs

the Citarum will end in the Java Sea. The

three breaks in the Citarum causes the river

to have less sediment load and pollution

between the reservoirs.

Residents use the reservoir for

commercial and non-commercial fishery. They have houses and nets in the middle of the

reservoir. The middle of the reservoir is the safest place. When the dam opens its gates

there will be heavy suction forces.

A global representation of the area is given with important knowledge about the river course,

the elevation differences and the land uses. This data will be used to calculate the amount of

sediment movement and to investigate the check dam location.

Figure 7 Waduk Jatiluhur Dam and Citarum

12

5 Requirements

In the previous sections the problem and the study area are set out. In this, the problem

analysis makes clear that the solution is found in a check dam instead of land type changes.

This section contains the requirements for the design process of the dam for research

question 2a.

There are requirements for weirs or check dams to meet. For instance, it possesses the

expectations of the head of the assignment and the wishes of the users. The next

requirements (table 6) were obtained from Food and Fertilizer Technology Center for the

Asian and Pacific Region [1995] and by consulting the supervisor and principal of this project,

Dr. Wagiono.

Because of the incompleteness of this list of requirements there is space for advice

about: dam type, river profile, dam material, dam performance, dredging, underground,

sediment and the expenses. The dam performance will consist of capacity, expiration time,

stability, seepage, outflanking and rising by water pressure. While the requirements are

compared with the choices, also the other specifications are mentioned to underpin the

selection.

Appendix G shows in which section the requirements are used. What is more, the

table tells also where requirements are not yet validated, but assumed to be without

constraints.

13

Code Type Requisite Source Status

EM1 Environmental Upstream location to keep the

sediment high in the catchment area

and minimize the sub-watershed

Literature Negotiable

EM2 Idem Narrowest sections of river for the

cheapest dam


EM3 Idem Not located in bend to prevent

spinning out and inundation

Literature Mandatory

EM4 Idem No inundation upstream for houses &

building and cultivation

Interview Mandatory

EM5 Idem No erosion downstream around the

dam in turbulent zone

Interview Mandatory

PM1 Performance Permanent dam based on 25 year

peak discharge


PM2 Idem Able to treat watershed of 72 km2 or

smaller


PM3 Idem Longest lifetime for a cheaper dam

and regarding US1

Interview Negotiable

PM4 Idem Maximum height for largest

sedimentation capacity

Interview Negotiable

PM5 Idem Conduction of flow on spillway to

prevent unwanted forces on the dam


PM6 Idem Construction dimensioned against

damaging obstacles


PM7 Idem Hydraulic jump forced in front of dam Literature Negotiable

PM8 Idem Safe construction with regard to

stability


TC1 Technical Downstream dam slope is between

20% and 30%


TC2 Idem Upstream dam slope 45% or larger Literature Negotiable

PS1 Physical Perpendicular to the flow direction and

the river banks


US1 User Minimum maintenance required in

order to obtain a cheaper dam

Interview Mandatory

Table 6 Requirements

14

6 Location

The requirements are essential to make the decision about the location of the check dam.

With the exact location, data and information can be collected about the sediment and the

river. The consideration of four vantages is treated in this section.

The location of the check dam will be in the upstream of the main Cilalawi River to maintain

sediment high in the catchment area. The slope in this area is approximately 0.4% (section

4.6). During the second visit there was site seeing at four points to see the complete river

(figure 8) to determine the most obvious section for the exact location.

Figure 8 Cilalawi Upstream Side Investigation Points

15

These four vantages were:

A. Anjun North

B. Anjun Northeast

C. Babakansari East

D. Babakansari Southeast

Point A and point B have almost the same flow

velocities, because width and profile seem

similar. The river has the largest width in this

section. In addition, at Anjun North a smaller

river is inflowing. The section with the highest

flow velocities and incised channel is point C.

The river is the narrowest at this location and is

surrounded by forest with in lesser amount

sawah and gardens. The last point, D, is

Babakansari Southeast. The river here is

fluctuating in width with one large sand bank in

the middle of the river. This location upstream

gives high flow velocities with sufficient width

and height in river profile to counter large

discharges.

With the requirements from the previous

chapter section C Babakansari East is chosen.

Firstly, the location is in the upstream, which

means that sediment is kept as much as

possible in the origin (requirement EM1). Secondly, this is the narrowest part of the river in

the upstream section (requirement EM2). Thirdly, the indicated river section is practically

straight and shows no bend (requirement EM3). Fourthly, large surface area of forest near

the riverside surrounds this area (requirement EM 4). This should mean safety in

circumstances with abnormal high discharges and inundation. This will be validated within

the check dam design. Furthermore, due to the small river profile at that location the flow

velocity is high and contains consequently high sediment transport. The check dam can

reduce the flow velocities, especially with the reservoir behind, with the result that sediment

movement is reduced.

A third visit to the river was of important to determine to exact location of the check

dam (figure 9). The support for this location is given in Appendix H. The check dam is placed

30° with respect to the north arrow with the coordinates S 06°37'29.8", E 107°24'25.6". This

is in order to meet the perpendicular requirement (requirement PS1). It is located 70 m

upstream of the bridge in front of the narrowest river profile. The sand bank surface will

become a reservoir. In this scenario, sand can be deposited in the created reservoir instead

of in the smallest profile. This location has as stakeholder the residents, who are using the

river for sediment supply. With the chosen location residents are still be able to use the river

to exploit sand and rock for road construction.

Sediment is collected and analyzed in the next section due to the known location. The above

stated location analysis started the design phase, which is more developed in the coming

sections about the river model and check dam design.

Figure 9 Check Dam Location by Google Earth

[2011]

16

7 Sediment

This section treats the soil in and around the river. One sand sample of the riverbed has

been classified by particle analysis in the laboratory. This sample and its characteristics are

useful to the river sediment transport modeling. The material on the bed of the Cilalawi River

is mainly coming from hill slopes with different forms of land use. Hence, the rational runoff

formula is used for a catchment area up to 10 km2 surface area [Booij, 2007]. The

information mentioned in this section is still part of research question 1, comprehensive the

characteristics.

7.1 Classification

The sieve and particle analysis by diameter size and passing is made with one soil sample of

the riverbed gathered at location Anjun Northeast (figure 8). The equipment and total

procedure of the analysis is mentioned in Appendix I. The U.S. Standard Sieve Series are

used in this test. The soil density results are shown in the table 7. The porosity is calculated

at 0.46.

!"#$#%&'&$! ()'&$#'*$&!+#,*&! -&.'!+#,*&! /0)'! 1&.2$)3')40!

35! '&!!!' $()*' +,-.*' /01'2034516'

36! $7(!' $7$$' +,-.*' 89:+'2034516'

3.! &%7!' &)(;' +,-.*' <=0>5?5>'2034516'

Table 7 Wet, Bulk and Specific Density

The outcome is also the sieve curve in figure 10. Measuring all the used sieves in weight,

converted to percentages, generates this curve. The cumulative percentages will draw the

graph. The graph shows that 10% of the mixer finer (d10) is 0.19 mm, 50% finer (D50) is 0.53

mm and 90% (D90) finer is 4 mm.

Figure 10 Sieve Curve of Cilalawi Sand Sample with d10, d50 and d90

17

7.2 Rational Formula

Large amounts of sand in the river are due

to the different land uses with cultivation

as dominator (sections 3.1 and 4.7). The

quantity can be calculated by the rational

formula of runoff [Schwab et al, 1983].

The formula makes use of rainfall data

and, for the sub-watershed behind the

check dam, a surface area of 51 km2

(figure 11). This surface area is 71% of

the total catchment area (Appendix J).

Assuming uniform properties concerning

terrain (geology and topography) this

means that approximately 71% of the 192

million m3 of sediment in 10 years, which

is the number 136 million, comes from this

region. This is similar with 13.6 million

m3/year of sediment. The assumption is

that the amount of rainfall in the Cisomang

River catchment area is similar to the

watershed. Therefore, rainfall data of the

Cisomang River is used.

The rational formula calculates 300 thousand m3/year of sediment runoff on land in

Appendix L. This number is approximately 2.1% of the 13.6 million m3/year of the river

sediment. This conclusion is not conform the hypothesis that majority of sediment

transported are from land. For this reason, these numbers and the sediment transport

quantities will be discussed in Chapter 10.

The calculated numbers of land use runoff can be compared with the results of the sediment

transport to get insight in the error of the modeled numbers with regards to the magnitude of

the different values. The river model consisting the sediment transport is the following phase.

Figure 11 Cilalawi Sub-watershed by Check Dam

18

8 River Model

The amount of sediment moving is the combination of flow velocity and sediment

concentration. Consequently, the river has transport of sediment by channel stream erosion.

Water will take material by flowing over stream banks or erode by scouring the bed during

(high) runoffs. Scour is heavy along the riverside, which is dependent on vegetation, flow

velocity, direction of flow, depth, width and soil type. This moving sediment will be disposed

at another location, which causes sandbanks and meandering, for instance.

The model used in this section is made by literature of Nortier & De Koning [1996]. An

overview of the used parameters without subscripts is found in Appendix M. Input value for

the sediment transport model is generated with the subsequent location description and

investigation. In particular, an average discharge of 5.54 m3/s is used to approach sediment

movement in 10 years. In contrast, to determine the check dam dimensions the maximum

discharge of 77.7 m3/s is used.

This section contains the phase for the modeling of the river and sediment movement

to complete research question 1.

8.1 River Profile

The third survey had as its main purpose the determination of the river profile (Appendix N)

to obtain a schematic profile for the use of the flow type and sediment transport modeling.

For the sediment transport model the average width is estimated, because the used formulas

are dominated by width and not by height. Therefore, an estimate width of 10 m is

appropriate for making assumptions about the sediment movement.

8.2 Sediment Transport

The flow and velocities during the survey in June for the wet river profile are shown in

Appendix O to estimate the average flow velocity, which was 0.55 m/s. In the same

calculations of the present flow the Reynolds number of 352000 (> 800) indicate a turbulent

flow. Owing to this, the flow is not in layers, which disturbs the bed with sediment.

The sediment that is taken in the flow can be divided into wash load, suspended load,

and bed load [Bendegom, 1971]. Firstly, wash load is the smallest grain size, which is during

the transport sans contact with the riverbed. Secondly, load that is suspended by a little

movement of the water will be in this condition for considerable time in hours to days. This

kind of load has the characteristic of bouncing with heights of more than 50 cm. One sample

of suspended load in water of the river took days to deposit in a 600 ml bottle, which was an

almost invisible layer of approximately 0.1 mm on the bottom. At last, bed load contains the

heaviest particles. This load will move by large flow velocities and shear forces between the

flow and the streambed. Suspended load and bed load (> 0.5 mm) can be caught in the

check dam for 100%, because these grain sizes are staying close to the bed. Bed load is

skipping 0 to 10 cm above the riverbed. In addition, this transport symptom is affected by

flow velocity, turbulence, size distribution, diameter, cohesiveness, specific gravity, channel

roughness and obstructions to flow [Schwab et al, 1983].

Flow Properties

To make the comparison with the total amount of sediment of 13.6 million m3/year (section

7.2), the average discharge of 5.54 m3/s is considered (Appendix P). As a matter of fact, the

real average discharge for the treated watershed is smaller, because the checkpoint for the

used discharge is more than 1 km downstream of the check dam location, which means a

larger catchment area. The difference is assumed to be insignificant.

The river in Appendix Q indicates being closely to the transition phase of sub- and

supercritical flow, because the equilibrium depth (0.31 m) is almost equal to the critical depth

19

(0.32 m). The smaller value means supercritical flow. This means also that upstream of the

narrow profile, the river is wider and with lower flow velocities. In short, the river is upstream

subcritical, which promotes a thrust curve.

To achieve the water depth results, data from survey from the wet river profile is

taken into account to make the first estimation of the Chézy coefficient, after which the

average discharge is used for an iterative process. The coefficient of 52 is used for the bed

movement in two sediment transport formulas.

Bed Movement

Appendix R calculates the sediment motion from the treated watershed into the reservoir

Waduk Jatiluhur by Meyer-Peter & Müller (bed load) and Engelund & Hansen (bed load and

suspended load), respectively 74.2 thousand m3/year and 88.9 thousand m3/year by an

average discharge of 5.54 m3/s.

In addition, the uncertainty of 50% in the formula of Meyer-Peter & Müller with the

scarce provided data, the low quantity of measurements, the diversity of the river conditions

and the fluctuations of the discharges can lead to higher uncertainty. The inconsistency in

transport formulas and results is discussed in Chapter 10.

What is more, the sediment coming from runoff on land in the watershed of 300

thousand m3/year is high. A conclusion from the comparison is that the rational formula is not

used correctly. The value also contains uncertainty, because the formula is designed for a 10

km2 watershed and not 72 km2.

The numbers calculated are essential for the design of the check dam and its properties. For

instance, the expiration time of the dam can be determined with the total amount of sediment

moving. This is one of the most important facets in this project, which lead to conclusions

about the impact and functionality of a check dam.

20

9 Check Dam Design

This section treats the check dam model, forms and dimensions. The expiration time for the

dam is the time until the area upstream of check dam is fully filled with sediment. Using the

amounts of sediment moving towards the dam from the previous section make assumptions

possible about the expiration to respond to research question 2b. The visualizing by

dimensions with forms in a technical drawing is to meet research question 2c.

9.1 Check Dam Alternatives

There are more than 14 types of check dams, which can be divided into 3 categories. The

first type of dam is the temporary dams for temporal use to establish vegetation around the

channel/gully. This solution is inexpensive, can be built rapidly and inexpensive. The second

kind of dams is the regular pervious dams. These are dams for the longer term with a

maximum life of 6 years and a maximum height of 1.5 meters. The third and last kind of dam

is the impervious dam. The different types of check dams are [Food and Fertilizer

Technology Center for the Asian and Pacific Region, 1995]:

Temporary dams

• Timber dam: brush dam, plank or log dam and

wood crib dam (figure 12)

• Wire mesh dam

• Sandbag dam

• Riprap dam

Regular dams (pervious dam)

• Dry masonry dam (figure 13)

• Gabion dam: wire sausage and wire box

• Fence dam: single and double

• Fire dam

• Concrete slab dam (figure 14)

• Concrete crib dam

Impervious dams

• Mortar rubble masonry dam with concrete core

(max. 2 m)

• Mortar masonry dam with rock core (max. 2 m)

• Concrete dam

• Brick dam (max. 2 m)

The temporary dams are only suitable for catchment

areas smaller than 10 acres (= 0.04 km2) [California

Stormwater BMP Handbook, 2003]. These dams are

not appropriate owing to 72 km2 of surface area for

the concerning watershed (requirement PM2 in

Chapter 5).

The regular dams are having limitations in

lifetime. Hence, the impervious check dams are used

in this project, because it knows lesser constraints in

this matter (requirement PM4). Furthermore, the impervious dams have the highest safety

and the need of low maintenance (requirement US1). Within the impervious dams, the

Figure 12 Plank Dam 3D

Figure 13 Masonry Dam 3D

Figure 14 Concrete Slab Dam 3D

21

concrete alternative guarantees no height limitations (requirement PM3) and is firmest

construction (PM8). The design process will continue with the concrete check dam.

9.2 Model

The purpose of the check dam is to catch 100% of bed load and suspended load, which is

88.9 thousand m3/year. The result of a dam in an active channel and sediment movement is

given in figure 15. In the upstream the sediment transport is towards the dam. There is the

gathering of the soil. After the low flow velocities upstream there will be supercritical flow on

the spillway, causing turbulent and erodibility downstream.

Figure 15 Dam Impact

The maximum discharge (Qmax) of 77.7 m3/s is found on 19 February 2002 (Appendix P).

This is the normative discharge for the design of the check dam. The dam will be designed

with the maximum width of 15 m for the reason of guidance in the narrow profile downstream,

'so that the spilt water is kept from

damaging the banks' [Food and Fertilizer

Technology Center for the Asian and

Pacific Region, 1995]. In reality the river is

staying around half the maximum 22 m

width in the middle of the profile (figure

34). For example, see figure 16.

Furthermore, in figure 17 the

situation of heights is shown. The height

of the dam depends on the maximum

water depth until inundation (htot), the

height of caught sand (hs), free water

depth behind the dam (hf), the water depth

on the spillway (a) and the height between

water surface and top of the river bank

(ht). The check dam height (hcd) is the sum

of free water depth plus the sand layer

height.

The depth of the spillway water can be calculated knowing the critical flow at that point (hc).

The critical flow velocity and the discharge formula are used to complete the calculation.

Assuming that the equilibrium depth of the subcritical flow (h) is the same as the

specific energy (He) due to the low flow velocities in front of the dam. The kinetic energy is

therefore insignificant compared to the water depth.

htot = hs + hf + a+ ht

hcd = hs + hf

Figure 16 Inspiration Check Dam Plipiran, Bruno,

Indonesia, with Narrow Spillway by Panoramio.com

22

v = g !hc with hc =2

3He =

2

3h

Q = Av = 2

3hb 2

3hg

" 77.7 = 2

3h !15 2

3h !9.81

" h = 2.10 m

The height of the check dam is equal to the depth of overflow during the designed peak flow

(requirement PM1). The distance between the maximum water level and the top is given in

the next calculation. The maximum water depth until inundation (htot) of 5.15 m is presented

in Appendix N.

h = a = hcd = 2.10 m

htot = (hs + hf )+ a+ ht = hcd + a+ ht = 5.15 m

! ht = htot " (a+ ht ) = 5.15" (2.10+ 2.10) = 0.95 m

Figure 17 Dam Aspect Heights

The sedimentation depth behind the dam will be 1.5 m. For this reason, there is (2.1 - 1.5 =)

0.6 m left of free water, which is of importance for the bed load, saltation and suspended load.

The height of the free water in this case is larger than the jumping height of the suspended

equal to or larger than 50 cm.

Knowing the thrust curve of the check dam (figure 18), the maximum amount of soil

can be determined and the moment of dredging.

Figure 18 Dam Thrust Curve

The curve is approached by the formula mentioned below [Nortier & de Koning, 1996]. The

outcome is shown in table 8. The dl is the rising of the water depth in distance to the

disturbance (m), d0 is the thrust at the location of the disturbance (m), i is the bed gradient, l

is the distance until the disturbance (m) and he is the equilibrium depth (m) (Appendix R).

23

hcd= 2.1 m

hc= 0.32 m

d0= h

cd! h

c= 2.1! 0.32 =1.78 m

e = 2.72

i = 0.004

160 m of the disturbance is the normal flow of the water.

The assumption is that the sedimentation will start here into

a triangle, because the sediment is inclined to settle

horizontally (figure 17).

The expiration time of the check dam is given in

Appendix S. The sedimentation layer with the maximum

height of 1.5 m and 0.4% in bed slope can contain 3000 m2

of soil (Vch).

The expiration time is determined by 88.9 thousand

m3/year of sediment (Qb) coming from the upstream

Cilalawi River.

texp =Vch

Qb ±100%!days

year=

3000

88.9 !103!365 " 12 days

With all the uncertainty in the parameters and the river modeling the expiration time could be

less than a day. In conclusion, daily dredging is required, when the discussed facts are taken

into account. This dredging can be arranged with the residents, who already use this river for

the sand and stone supply.

In contrast, the advice will be multiple check dams in this watershed starting in the upper

reaches, and/or dredging behind the dam in order to deepen the channel. In the first option

dams treat a smaller catchment and have expiration times larger than a few days. In that

case, research is required starting in the upper reaches. The second option of dredging is

expensive and the impact is smaller than the first, because the activity is limited in water

depth.

For multiple check dams mapping of the

entire watershed and dividing it into sections is

required. The expiration time need to be the same for

every check dam and long enough so dredging can

be planned in a timeline with sufficient clearance.

Hence, after the dividing of the complete area the

treated surface area sections, the river properties and

sediment transport need to be analyzed to achieve a

coherent design.

9.3 Dimensions

Dams consist of several parts with different

characteristics and dimensions. The parts spoken of

dl= d

0!e

"3!i!l

he

Distance (m) Depth (m)

0 1.78

10 1.22

20 0.84

30 0.58

40 0.40

50 0.27

60 0.19

70 0.13

80 0.09

90 0.06

100 0.04

110 0.03

120 0.02

130 0.01

140 0.01

150 0.01

160 0.00

Table 8 Thrust Curve Results

Figure 19 Check Dam Parts by Food and

Fertilizer Technology Center for the Asian and Pacific Region [1995]

24

in this section are: dam (1), spillway (2), sidewalls (3), apron / stilling basin (4), wings (5) and

end wall/sill (6) (figure 19) [Food and Fertilizer Technology Center for the Asian and Pacific

Region, 1995].

The first dimension is already determined in the previous section, which is the 2.10 m

check dam height due to the maximum discharge (requirement PM1). This height is without

inundation in the upstream (requirement EM4)

Dam (1)

Dams have also two surfaces slopes including downstream and upstream. The downstream

surface has a 30% slope (requirement TC1). The steep dam slope is in order to prevent

damage from stones and trees in during high discharges. The less steeper slope of 30% is to

reduce the gravitation forces on the object by shear forces on the dam side, which will again

prevent damaging the apron by smaller impact of the object.

The upstream side slope of the check dam should be larger than 45% (requirement

TC2). By making the slope larger, sediment will have the opportunity to take the ramp easier

during high flow velocities in the overflow. For this check dam is the minimal downstream

slope of 45% is used.

Spillway (2)

The spillway will be the Creager design, rounded spillway (figure 20). The hydrostatical

pressure and the centrifugal powers are working together in the rounding. When the radius of

the rounded spillway is too small, water will leave the dam causing suction forces

(requirement PM5). To prevent this kind of situation, the radius (r) should be approximately

70 to 100% of the equilibrium depth above

dam (2.1 m) [Nortier & de Koning, 1996].

The dam will be larger and more

expensive when 100% of the height is

used. 70% would not be appropriate when

there is an higher discharge than 77.7

m3/s. Consequently, 85% will be used,

which is the same as 1.79 m.

Sidewalls (3)

The rocks that impact the apron can also come into contact with the sidewalls and wings

(requirement PM6). As a consequence, the sidewalls have a thickness of 0.30 m as the

apron and will have the diameter of the spillway, which is 3.58 m. Furthermore, the sidewalls

will have the maximum river profile height of 5.15 m.

Apron (4)

An apron is used downstream for protecting the foundation from water erosion. The

thickness of the construction depends on the dam height (table 9) and whether the water

contains (floating) damaging objects and heavy gravel.

Dam Height (m) Material Apron Thickness (m)

< 2 Concrete 0.20

2-3 Concrete 0.20-0.30

3-5 Concrete 0.30-0.50 Table 9 Apron Thicknesses by Food and Fertilizer Technology Center for the Asian and Pacific Region

[1995]

The thickness of the apron will be 0.30 m, because the river can contain large rocks.

Figure 20 Creager Spillway

25

The length and presence of the apron depends on the highest water level differences

between the downstream and upstream, and the maximum discharge. The calculation is to

be found in Appendix T. For this reason the stilling basin has a minimum of 7 m in length

following a barrier of 0.5 m. This half a meter wall will assure any hydraulic jump against the

dam (requirement PM7). A flat concrete slab of 5 m will be after the basin with 0.30 m

thickness. Lastly, one collapse bed is built of 10 m in length, constructed from heavy rocks.

The concrete slap and the collapse bed are both to ensure no erosion downstream

(requirement EM4).

Wings (5)

The wings will have the same thickness of 0.30 m as the stilling basin for damaging of

obstacles taken by the flow. What is more, the wings will be 5.15 m high in the connection

point with the sidewalls and decrease to 2.5 m at the end of the stilling basin. This is because

the maximum discharge involves water depth downstream of 1.74 m. The wings prevent

erosion in the unsteady flow downstream close to the dam (requirement EM5).

End Wall (6)

This end wall length is between the 0.2 and the 0.6 m [Food and Fertilizer Technology Center

for the Asian and Pacific Region, 1995]. The maximum of 0.6 m will generate the maximum

counteraction against flowing water under the construction.

9.4 Underseepage and Outflanking

Underseepage of the check dam needs to be minimized by the length of the dam including

the apron. Consequently, the law of Darcy is applied in Appendix U. The minimum length of

the dam is in the calculations 0.79 m. So, the already determined apron of 7 m solves this

problem (requirement PM8).

Outflanking is not taken into account for the reason that the banks of the river consist

of rocks. The wings of the check dam can be constructed straightly to wall of rock and

installed by civil anchors in. These assumptions are made by site-investigation. The real

structure of the soil should be investigated by geotechnical research.

9.5 Stability

The dam needs to sustain the horizontal en vertical water pressure to prevent unwanted

movement. The weight of the dam, the shear forces under it and the hydrostatic pressure will

determine collapsing. In Appendix V it is proved that the check dam is stable. The rising is no

risk as result of observed rocky environment. Thus, water cannot move to and built pressure

under the structure (requirement PM8).

The technical drawings and preliminary drawings of this check dam are shown in Appendix

W.

26

10 Discussion

This discussion section starts with the results of the river and sediment transport modeling.

There is large uncertainty in these numbers due to assumptions, rules of thumb and

diversity/fluctuations in the real situation. What is more, is the design discharge used for the

dimensions of the check dam and the verification table for the requirements.

10.1 Parameter Uncertainty

The average discharge is the right number for yearly discharge and knowledge about water

quantities, but for the sediment transport is it useless. In the formula of Meyer-Peter & Müller

(MPM) and Engelund & Hansen (EH) different power are used for the flow velocity,

respectively v3 and v5 (figure 21).

MPM:

EH:

The discharge (Q) is closely related to the flow

velocity (v). The power is causing a different

relation with the runoff (Qsed and sbs) in

comparison with the average taken discharge,

which is referring to a linear relation.

Hence, when flow velocities reduce,

sediment transport will rapidly decrease.

Importantly, this will extend the expiration time.

Yet, increasing velocity leads to larger amounts of sediment transported entering the check

dam. For instance, long periods of flow velocities below 5.54 m3/s (average flow velocity

2000-2009) will extent the expiration with possible days. Therefore, with a higher discharge

the dam will be filled in a few hours, according to the modeled sediment transport, but still the

expiration time will be days due to the previous period of low discharge. In case of

continuously high discharge the check dam will be sediment overcrowded each day,

eventually causing total sediment moving downstream.

In other words, 5.54 m3/s is a value, which is not including the powers of the formulas

and the different discharges, which are occurring over time (tables 37 to 45). Moreover,

because sediment movement begins with the flow velocity of 0.014 m/s (Appendix U) it can

be confirmed that the normative discharge must higher than the average.

10.2 Sedimentation Inconsistency

It is said that the Cilalawi River (average discharge 5.54 m3/s) with 72 km2 catchment area

supplies 192 million m3 sedimentation in 10 years to reservoir Waduk Jatiluhur. For the sub-

watershed treated by the check dam this amount is approximately 136 million m3 in 10 years

(13.6 million m3/year).

A comparison is made with the Serayu Mrica reservoir in Central Java, Indonesia.

Due to investigation in 2005-2006 it is noted that the reservoir suffers high sedimentation and

Qb =16b !v

Ck

"

#$

%

&'

2

( 0.08d50

"

#

$$

%

&

''

3

2

Qbs = 0.03!g

C2

"

#$

%

&'

3

2

!v5

g2 !d

50

"

#$$

%

&''!b

Figure 21 Meyer-Peter & Müller and Engelund

& Hansen

27

storage decreasing just like reservoir Waduk Jatiluhur. The Serayu River (average

discharge 57.16 m3/s) [Hidayat Pawitan, A. W. Jayawardena "K. Takeuchi & Soontak Lee,

2000] section flowing into the reservoir includes a catchment area of 1022 km2 [Soewarno &

Petrus Syariman, 2008: 17]. This area is generating 2.2 to 7.0 million m3/year of

sedimentation.

The number 13.6 million m3/years of the Cilalawi River is not in the same order of

magnitude as the large transportation 7.0 million m3/years of the Serayu River, when the

average discharges and catchment area sizes are taken into account. These numbers

contain an observed inconsistency of the factor 10 or more, resulting in at least 1.36 million

m3/years of the Cilalawi River.

10.3 Design Discharge

The maximum discharge for the design of the check dam is 77.7 m3/s. This number is

derived from the available tables of discharge in 9 years given in Appendix P. In other

discharge data of the PSDA the maximum (calculated) discharges are mentioned as 278.44

m3/s on 25 October 2001. Data of the same organization on this subject mentions 33.5 m3/s.

Besides, the number of 278.44 m3/s is too large for the Cilalawi River. The reliable 77.7 m3/s

is used.

10.4 Verification

In Chapter 5 and Appendic G the 17 requirements are summed and referenced. All the

requirements are validated throughout the report. This section speaks about the verification

and if the system meets the expectations. In table 10 all the requirements are mentioned in a

short confirmation.

Requirement Code Confirmation

EM1 The dam location is in the upstream of the river in the East of

Babakansari.

EM2 The dam is in front of the narrowest section of the river.

EM3 The dam is practical not in a river bend.

EM4 The dam is designed with no inundation upstream.

EM5 The dam is designed with no erosion in the downstream by wings

and apron.

PM1 The dam is designed on 25 year peak discharge.

PM2 The dam is design for a watershed 72 km2 of smaller.

PM3 The dam is designed including the longest lifetime.

PM4 The dam has the maximum height with due consideration of

maximum sedimentation and upstream inundation.

PM5 The dam has a Creager spillway against tensile.

PM6 The dam parts thicknesses are dimensioned on possible damaging

obstacles.

PM7 The dams has a smaller dam creating an apron, which is forcing

the hydraulic jump.

PM8 The dam is made of concrete ensuring safety and stability.

TC1 The dam slope of the downstream is 30%.

TC2 The dam slope of the downstream is 45%.

PS1 The dam is built perpendicular to the flow direction and river banks.

US1 The dam of concrete requires minimum maintenance. Table 10 Requisite Verification

28

11 Conclusion

The Cilalawi River provides an overdose of sediment going into the reservoir Waduk Jatiluhur.

According to the PJT II Purwakarta it is 274 million m3 sediment in 10 years. This is causing

water storage reduction. Check dams can limit the sedimentation process, which is one of

the recommendations. In the first phase of the project research questions are generated. An

elaboration of each question will be given in this chapter.



Chapters 3, 4, 7 and 8 provide answers to this question. There are different land uses with a

dominant sawah involved in the watershed of the active river. This land use is erodibility

sensitive and is the main producer of sediment in the runoff by rainfall.

There are large elevation differences in the upper reaches, decreasing till the river

reaches the reservoir. This means high flow velocities, erosion and sediment transport in the

upstream. Moreover, the river from the upper reaches is already filled with suspended and

wash load.

The land use in this region is providing 300 thousand m3/year and the river has a

sediment transport of 88.9 thousand m3/year as shown by Engelund & Hansen. The region

treated must generate 13.6 million m3/year, according to PJT II Purwakarta, but as result of a

discussion the value is assumed to be 1.36 million m3/year. There is a high uncertainy in the

values of the transport model, because of the inaccuracy in the parameters.


Chapter 5, 6 and 9 give the answers to the sub-questions.


17 requirements for the location and check dam design are collected. First of all,

environmental requirements minister to locate the dam in a practical straight upstream

section with the narrowest profile. The design prevents inundation upstream and erosion in

the downstream. Secondly, for the performance of the check dam is required: 25 year peak

discharge, ability to treat a watershed of 72 km2 or smaller, the longest lifetime, maximum

height, conduction on spillway, constructed against damaging obstacles and a forced

hydraulic jump. Lastly, the technical and the physical requirements ask for a(n): downstream

dam slope of 20-30%, upstream dam slope of 45% or more, dam positioned perpendicular to

the flow direction and river banks, and minimum maintenance required.

b) What does the designed check dam look like in the phase of preliminary design?

The figure of the check dam as preliminary is shown in Appendix W. The above-mentioned

requirements are verified to conclude that the dam meets the expectations. The designed

check dam contains six parts: dam, spillway, sidewalls, apron, wings and end wall. The dam

is 2.1 m high with a semicircle spillway ('Creager spillway') containing a radius of 1.79 m. The

dam slopes under the spillway are designed by rules of thumb. The two sidewalls in an angle

towards the bottom of the dam apron are designed with 0.3 m thickness and 5.15 m height

decreasing to the downstream. The apron for the hydraulic jump is 7 m between the actual

dam and the end wall of 0.5 m. This little dam with the same dam slopes as the spillway is

forcing a hydraulic jump. The last parts are the wings, of 5.15 m in height, standing as large

pillars next to the spillway. They are 3.58 m in width, the same as the spillway diameter. The

dam is mainly concrete, except the sidewalls and the wings. These contain environmental

rocks combined with concrete.

29

c) What will be the time horizon of the check dam till its expiration?

The time of expiration is 1 until 12 days, concerning an average discharge or less in rainy

season. The overall conclusion is, that a functional check dam is designed. Nevertheless, the

expiration time is extremely short due too the small volume of 3000 m3 of the check dam.

The advice is to design and built more check dams in sequence to establish smaller sub-

watersheds, before the building of the dam designed in this report, because deepening the

channel is an expensive activity with lesser impact. Importantly, the expiration time of

subsequential check dams needs to be the same for every dam and long enough for timeline

planned dredging. Hence, after the dividing of the complete area, the several river properties

and sediment transport need to be analyzed to achieve a coherent design of each new check

dam.

30

12 References

Articles

Aqil, M. Kita, I. Yano, A. & Nishiyama S. (2006) A Takagi-Sugeno Fuzzy System for the

Prediction of River Stage Dynamics, JARQ, Vol.40, No.4, p.369-378.

Fakultas Teknologi Industri Pertanian, Universitas Padjadjaran (2009) Stochastic Model for

Simulation of Landuse Changing to Erosion Relation on Cikapundung Gandok Catchment

Area, Jurnal Teknotan, Vol.2, No.2, p.84-87.

Singh, M.J. & Khera, K.L. (2008) Soil Erodibility Indices Under Different Land Uses in Lower

Shiwaliks, Tropical Ecology, Vol.49, No.2, p.113-119.

Soewarno & Petrus Syariman (2008) Sedimentation Control: Part II. Intensive Measures The

Inside of Mrica Reservoir, Central Java, Journal of Applied Sciences in Environmental

Sanitation, Vol.3, No.1, p.17-24.

Books

Bendegom, L. van (1971) Algemene Waterbouwkunde, Delft (Netherlands): Technische

Hogeschool Delft, 159p.

Bezuyen, K.G. Stive, M.J.F. Vaes, G.J.C., Vrijling, J.K. & Zitman, T.J. (2007) Inleiding Waterbouwkunde, Delft (Netherlands): Technische Universiteit Delft. 319p.

Bischoff van Heemskerk, W.C. (1964) Vloeistofmechanica. Delft (Netherlands): Technische

Hogeschool Delft, 70p.

Booij, M.J. (2009) Inleiding Waterbeheer. Enschede (Netherlands): University of Twente,

138p.

Food and Fertilizer Technology Center for the Asian and Pacific Region (1995) Soil

Conservation Handbook. Taipei (Taiwan, China): Food and Fertilizer Technology Center for

the Asian and Pacific Region, 451p.

Nortier, I.W. Koning, P. de (1996) Toegepaste Vloeistofmechanica. Groningen/Houten

(Netherlands): Wolters-Noordhoff, 489p.

President of the Republic of Indonesia (2010) Indonesian Government Regulation - Number

7. The Chief of Berau of Industrial and Economy, Jakarta (Indonesia): President of the

Republic of Indonesia, 33p.

Ribberink, J.S. (2007) Shallow - Water Flows. Enschede (Netherlands): University of Twente,

121p.

Ribberink, J.S. (2007) Transport Processes and Morphology. Enschede (Netherlands):

University of Twente, 93p.

Schwab, G.O. et al. (1983) Soil and Water Conservation Engineering. New York (United

States of America): Wiley, 525p.

31

Setiawan, S. (2010) Kajian Sedimentasi Waduk Berdasarkan Kondisi Tataguna Lahan Studi

Kasus Waduk Sermo Kabupaten Kulon Progo Provinsi Daerah Istimewa Yogyakarta.

Yogyakarta (Indonesia): Universitas Gadjah Mada, 57p.

Soemarwoto, O. Boerboom, J.H.A. (1978) Project Tropical Ecology - Vegetation and erosion

in Jatiluhur Region. Bandung: Padjadjaran University & Agricultural University

Indonesia Infrastructure Initiative (2010) Jatiluhur - Jakarta Pipeline And Water Treatment

Plant Pre-feasibility Study, Jakarta (Indonesia): GHD, 23p.

Tim Pemeruman Waduk Ir.H.Djuanda (2009) Laporan Pekerjaan - Pemeruman / Bathymetri -

Waduk Ir.H.Djuanda - PJT II Puwakarta (Indonesia): Perusahaan Umum Jasa Tirta II, 21p.

Vlotman, W.F. (1989) Discharge Measurement Structures. Wageningen (Netherlands): ILRI,

27p.

Vos, G.J. (2011) Erosion and Sedimentation Control by Check Dam in the Cilalawi River -

Preliminary Report - Bachelor Thesis. Enschede (Netherlands): University of Twente, 24p.

Websites

California Stormwater BMP Handbook (2003) Check Dams SE-4. Retrieved, April 11, 2011 from

http://www.cabmphandbooks.com

Hidayat Pawitan, A. W. Jayawardena "K. Takeuchi & Soontak Lee (2000) Kali Serayu.

Retrieved, June 15, 2011 from

http://flood.dpri.kyoto-u.ac.jp/ihp_rsc/riverCatalogue/Vol_03/03_Indonesia-8.pdf

Khan, H.J. & Shinwari M.Q. (2010) Sieve Analysis and Particle Analysis of Size & Passing.

Retrieved, May 29, 2011 from

http://www.aboutcivil.com/Sieve-analysis-and-soil-classification.html

Piranha Pumps & Dredges (2011) Piranha - Gasoline Engine Dredge Model PS135E.

Retrieved, June 19, 2011 from

http://www.piranhapumps.com/PS135E_1.html

32

13 Appendices

Appendix A Flow Chart

The flow chart (figure 22) represents the steps undertaken in the project. The basis was the

preliminary report, which was constructed by consultation between supervisor/expert, the

assignment of the Padjadjaran University and a literature study at the University of Twente.

The main route is preliminary report, project description, problem analysis, exact

location, river modeling and check dam design. The short description of these phases is

given in the boxes with an angle in the sidelines. This plan results in the thesis. There are a

few parallel activities to support the main activities. For instance, literatures study, river site

investigation and survey.

Figure 22 Flow Chart of the Project in River Engineering

33

Appendix B List of Data

river course

river slopes or elevation map

length of slopes

map of catchment area

land use

hydrographics

discharges

water levels

precipitation

river profile

heights

widths

bed form(s)

alluvial roughness

vegetation parameters

sediment data

composition (for example, American Geographical Union)

density

shape factor of sediments

34

Appendix C Interview PJT II Purwakarta

1. List of Data.

The list of data is shown to derive all the data/properties on the river.

2. Literature of Cilalawi River.

This is to find all the data about the river in written sources.

3. What is the current policy for the Cilalawi?

The function of the Cilalawi and its regulation is the purpose here.

4. What is the current policy for the Waduk Jatiluhur?

In this question the focus is on the function and regulation of the Waduk Jatiluhur.

5. What are the futures plans for the reservoir and the river?

For example, having the goal of reduction of toxins, sediment reduction, accessible

for boats, possibility of fishing.

6. What are they used for?

The question is there to discover who is using these waters and with what purpose.

7. Impact of river on reservoir?

This is asked to reveal what the result is of the Cilalawi flow into the reservoir.

8. Water level changes in the reservoir due to the Cilalawi River?

This is to see the impact of the Cilalawi on capacity of the reservoir.

9. Problems in and around the river and reservoir.

This treats problems like inundation in both waters, water quality issues, etc.

10. Previous check dams in the reservoir.

For the design of the check dam the requirements and location of an expired check

dam can support the design process.

35

Appendix D Catchment Area of Cilalawi River

Figure 23 Sub-watershed and Land Use of Cilalawi River by Padjadjaran University (Bandung, Indonesia)

and Agricultural University (Wageningen, The Netherlands) [1978]

36

Explanation sections Cilalawi catchment area in figure 23 are given in table 11. The

geomorphology in staight contact with the river is bolded.

No. Geomorphology Soil Land Use Slope

(%)

1 Moderately dissected hills of

Miocene deposits

Complex

latosol/regosol

Dryland agriculture 8-25

2 idem idem Mixed Gardens 8-15

3 Moderately dissected hills

of intrusive origin

idem idem 15-40

4 idem idem Intermittent cultivation 15-25

5 Complex of intrusive necks idem idem > 40

6 idem idem Mixed gardens/sawah 25-40

7 idem idem idem 8-15

8 idem idem Intermittent cultivation > 40

9 Isolated intrusive necks idem Shrubs/intermittent

cultivation

> 25

10 Footslope of volcanic tuff Grey

hydromorphic

Sawah 8-12

11 Slightly/moderately dissected

volcanic deposits

Regosol idem 0-2

12 idem Grey

hydromorphic

idem idem

13 Slightly/moderately dissected

volcanic deposits

Red Latosol Mixed gardens/sawah idem

14 idem idem Dryland cultivation 2-8

15 idem idem Mixed gardens/sawah idem

16 idem idem Sawah & village 0-2

17 Slightly dissected volcanic

deposits

Complex

latosol/grey

hydromorphic

Sawah idem

18 Undissected alluvial deposits Grey

hydromorphic/

low humic gley

Sawah & brick

factories

idem

19 Ancient volcanic foot slope Red Latosol Mixed gardens 8-25

20 idem idem Rubber 15-25

21 idem idem Shrub & forest 15-25

22 idem idem Dryland cultivation 15-40

23 Valley with moderately

dissected Miocene deposits

Complex

regosol/Iatosol

Sawah 15-25

24 Strongly dissection Complex

litosol/regosol

Dryland cultivation 25-40

Table 11 Land Uses Cilalawi Watershed [1978]

37

Appendix E Elevation Map Catchment Area of Cilalawi River

In this section will speak of the relief and height differences in the Cilalawi River. The

elevation map is to be representative for the river slopes (see figure 24). In this map there

are contour lines given with heights in meters. Two following lines differ 12.5m from each

other. The sections are zoomed-in in the figures 25, 26, 27 and 28.

The river can be divided into 4 sections. The first section is above the Cilalawi before

the two smaller rivers combine, the upper reaches. The next three sections are the upstream,

middle reaches and downstream. This subdivision is based on the schematic contour map.

The point of division is the contour line crossing the river.

To determine the slope of the river elevations, lengths and one curvimeter are

required. The curvimeter units are not used. The outcome is used as comparison to achieve

factors. The factor for every river section converts the differences between the distances as

the crow flies (black line) in the meandering length (blue line). The straight length with the

factor gives the real length in meters (see table 12). The accuracy is with 10 meters.

Section of

Cilalawi!7&#,!,&08'9!

.'$#)89'!

:%;!

<*$=)%&'&$!

>'$#)89'!:?;!

<*$=)%&'&$!

7)=&$!:?;!

@#2'4$!! 7&#,!

(&08'9!

:%;!

A94,&!

0*%6&$!

:%;!

Upper Reaches! 7&!!' &#"7' *!"7' $"&#7' %#)#' %#;!'

! *(!!' $("7' &7"7' $"*$' 7$!$' 7$!!'

! #%&7' &;")' *#"!' $"$;7' 7#;$' 7#;!'

Upstream! &&7!' &$"!' **"!' $"7)' *7*7' *7#!'

Middle

Reaches!$(!!' &*"!' *)"!' $"%$' *!7(' *!%!'

Downstream! &$!!' &#"$' &)"$' $"$&7' &*%!' &*%!'Table 12 Straight Lengths to Real Lengths

The upper reaches contain a diversity of small rivers. To make assumptions about the

gradient in that sections 3 river branches are used adjacent to the upstream of the main river.

The gradient is the elevation difference divided by the real length of the river section (table

13).

Section of Cilalawi Elevations (m) Elevation

Difference (m)

Real

Length (m)

Gradient (%)

Upper Reaches 212.5 - 262.5 50 %#;!' !";'

212.5 - 262.5 50 7$!!' $"!'

212.5 - 312.5 100 7#;!' $";'

Upstream 200 - 212.5 12.5 *7#! !"#'

Middle Reaches 150 - 200 50 *!%!' $"%'

Downstream 100 - 150 50 &*%!' &"$'Table 13 Gradients in the River Sections

It is evident that the highest gradients occur in the upper reaches. After this river section

follow respectively the middle reaches, the downstream and the upstream. The average of

the gradient of the three upper reaches gradients is 1.2%.

38

Figure 24 Elevation Map Catchment Area of Cilalawi River by Water Research Center (Bandung)

39

Figure 25 Downstream Figure 27 Upstream

Figure 26 Middle Reaches

Figure 28 Upper Reaches

Appendix F Land Use Map Catchment Area of Cilalawi River

This section treats the different land uses in the Cilalawi catchment area. The land uses

given in Bahasa Indonesia in the figure 29 are translated in table 14.

Bahasa Indonesia English

Air Tawar Freshwater

Belukar/Semak Shrubs

Gedung Buildings

Hutan Forest

Kebun Gardens

Pemukiman Houses

Rumput Grass

Sawah Irigasi Sawah Irrigation by River

Sawah Tadak Hujan Sawah Irrigation by Rainfall

Tanah Berbatu Stones and Rocks

Tanah Ladang/Tegalan Vegetables and Fruits Fields Table 14 Translation Land Use Bahasa Indonesia to English

The complete upper reaches are taken into account in this analysis. This part consists of

mainly sawah and buildings. Vegetables and fruits, shrubs and gardens are predominant in

the watershed. In the upstream sawah, buildings, vegetables & fruits, shrubs, gardens areas

are proportionally distributed. Besides, forest represents a small part at the borders of the

catchment area. The buildings disappear further on in the middle reaches. In the downstream

vegetables & fruits and sawah dominate. Buildings and shrubs use a small part of the area.

The vegetables and the rice fields are fed by the nutritious sludge in the river.

In table 15 there are the four sections of catchment area, described with their land

types. It can be said that irrigation by the residents and their houses contribute to filling

almost the total area of the Cilalawi catchment area.

Sections of Cilalawi Land Uses

Upper Reaches 15% Buildings & Houses

Idem 10% Gardens

Idem 10% Vegetables & Fruits

Upstream 65% Sawah


Idem 10% Shrubs

Idem 10% Buildings & Houses

Idem 5% Gardens

Middle Reaches 35% Sawah

Idem 25% Shrubs


Idem 10% Gardens

Idem 10% Forest

Downstream 30% Sawah

Idem 30% Gardens

Idem 35% Vegetables and fruits

Idem 5% Buildings & Houses Table 15 Cilalawi Sections with Land Use

41

Figure 29 Land Use Map Catchment Area of Cilalawi River by Water Research Center (Bandung)

Appendix G Requirement Validation

Validation is required to design a consistent object, which meets the requisite. The appendix

shows in which section the requirement is used (x). It becomes obvious that not in every

section validation is needed. The four subjects location, sediment, river model and check

dam in table 16 are parallel to Chapter 6, 7, 8 and 9.

Code Description Location

Analysis

Sediment River

Model

Check Dam

Design

EM1 Located upstream x EM2 Narrowst section x EM3 Not located in bend x EM4 No inundation upstream - x EM5 No erosion downstream - x

PM1 Designed on 25 years discharge x PM2 Treat watershed 72 km2 or

smaller x

PM3 Longest lifetime x PM4 Maximum height and capacity x PM5 Conduction flow on spillway x

PM6 Firm construction against

damaging x

PM7 Forced hydraulic jump x PM8 Safe construction x TC1 Downstream dam slope 20-30% x TC2 Upstream dam slope >45% x

PS1 Perpendicular to flow and banks x US1 Minimum maintenance x

Table 16 Requirements Section Validation

The demands E5 and E6 are in early phase assumed to be no constraint (-) when it is used

within the check dam design. Therefore, in the check dam design this will be checked.

43

Appendix H Location Check Dam

The location in figure 30 refers to the point in the narrowest section of the river. The higher

flow velocities with morphological changes result in a grounded river profile. Reduction in the

higher flow velocities in the upstream in this section support lesser sediment transport and

possible erosion of the rocky underground.

There is a bridge, which is an advantage for the building of the dam and the removal

of sediment, although, as a consequence of the bridge the check dam cannot be built

downstream, because the bridge is designed on discharges and water level of the river. A

check dam will modify these numbers. Besides, inundation due to these numbers will make

the bridge inaccessible.

The large sand layer upstream will become a small reservoir, which stimulates more

deposition. The current situation is that the sand layer deformed in a small bend with on the

left side the sand. This plateau and bend will become without flooding risk a small reservoir

for deposition of sediment and will be no constrain in the design.

The GPS equipment (eTrex Vista HCx) provided the exact coordinates of the location of the

check dam. The coordinates are:

S 06°37'29.8"

E 107°24'25.6"

The check dam makes an angle with respect to the north arrow of approximately 30°, which

is perpendicular to the flow direction and the river banks. Furthermore, the point is 70m

upstream of the bridge.

One constraint in the river can be the residents who are using the section for the

exploitation of sand and stones for road construction. Permitting them to remove the

sediment of the expired check dam, when the water depth of the artificial reservoir allows this,

can solve that problem.

Figure 30 Check Dam Location and Coordinate by Google Earth [2011]

Appendix I Soil Classification

This section is about the sand sample, which is

classified by the particle analysis in the sieve test.

The complete analysis from the wet sand sample to

the sieve results is mentioned.

The requirements for this test are:

• Sand sample

• Oven (blower)

• Measure glass

• Mechanical sieve shaker (figure 31)

• Scale

!The order of analyzing is first the characteristics of

the wet soil. Measuring the volume and weight in the

measure glass provides in the wet density (table 17).

This is using the general formula with ! for density

(kg/m3), V for volume (m3) and m for mass (kg).

!

!

!The same procedure needs to be applied for the bulk density (the dry soil sample) after

drying the sand in the oven blower.

!

!"#$% &'()*+%,(+*%

-."//%01)2%

&'()*+%34%

-."//%01)2%

&'()*+%34%

!"#$%01)2%

53.67'%0782% 9'#/(+:%01);782%

,'+% "#$%&! '#$"'! "#'(&! &#&)"'*+!

"%,-!

$<:% "#'(&! '#$&+! '#(-"! &#&)"'*+!

"&""!Table 17 Wet and Dry Density

The next table provides the results of the test with the values of the literature wrote by

Ribberink [2007]. The bulk density is the soil with pores. The porosity factor, which is

between the 0.3 and 0.4, needs to be taken into account to get the specific density (table 18).

This can be calculated by:

!

The formula contains the "p the share of pores in the soil, the vw for the volume of water in

the saturated soil (m3) and the total volume of the sample (m3). The total volume of the sand

is 550 ml. The amount of the water weight (mw) and the density of water (./ = 1000 kg/m3)

leads to an estimate of the volume of the water (vw).

vw=m

w

!w

=1.085! 0.831

1000= 2.54 "10

!4 m

3

! =V

m

!p=vw

vtot

Figure 31 Mechanical Sieve Shaker

46

When the formula for the granules in the soil is completed, the outcome of epsilon is 0.46.

!p=vw

vtot

=2.54 !10

"4

5.5 !10"4

= 0.46

This number is used with the bulk density to determine the specific density. To conclude, the

porosity parameter is 46% of the bulk soil.

The specific density is calculated by:

ps =pb

1!!p=

1511

1! 0.46= 2798 kg/m3

!

%% 9'/=<(>+(3#% ?(+'<"+6<'%5".6'% @'/+%5".6'% A#(+%

>,% /01!2034516! !$'''! "%,-! 789:-!

>B% ;<=7!2034516! "&%'! "&""! 789:-!

>/% 4>0?5@5?!2034516! $A&'! $,%(! 789:-!

Table 18 Wet, Bulk and Specific Density

The next step is to sieve the dry soil in the mechanical sieve shaker. First, the several sieves

need to be measured in weight (g) [Khan, H.J. & Shinwari M.Q., 2010]. The soil sample will

be put in the top sieve with the largest diameter. The smaller parts of the soil will fall through

large diameter sieve nets by shaking the soil sample in the sieve tower. When the diameter

of the grain is larger than the sieve, the sand will stay in that tray. The result is given in the

table 19.

C3D% !('E'%/(F'%

0772%

&'()*+%!('E'%0)2% &'()*+%!('E'%

,(+*%!"#$%0)2%

!"#$%0)2% G'<='#+")'%

G"//(#)%0H2%

I% B!+#,A! $%&#-+! -&"#,,! &A#+-! A#+!

JK% '#(+! -"+#$,! &%'#"+! $"%#++! $+#%!

8K% '#&%! $%-#%(! +$-#$+! "$%#$A! "+#,!

IK% '#+$"! -'%#%(! +'-#(,! %-#(%! "'#,!

LK% '#$&! $%A! &'&#",! $'%#",! $-#,!

MK% '#",,! $%%#&+! +'%#%(! ""'#++! "$#&!

NKK% '#"&! $%"#(+! -'+#+"! "$#&,! "#+!

NJK% '#"$&! $%$#$&! $%A#,%! +#&+! '#&!

B'$% C!'#"$&! "A,#$-! $"$#,-! +&#&! &#$!

+3+".% %% %% %% MMNDJI% NKKDK%

Table 19 Sieve Quantities Soil Sample of Cilalawi River

The number of the sieve is related to the U.S. Sieve Standard to obtain diameter to the sieve,

the sieve size. The last column gives the percentage of the total soil sample in the

concerning sieve. The weight of the total soil divided by the sand of one sieve gives the

percentage. When these percentages are summed from the bed and represented

cumulatively, the sieve curve can be achieved (figure 32) It is the plotting of the linear

percentages against the log scale of the grain size.

47

Figure 32 Sieve Curve Soil Sample of Cilalawi River%

48

Appendix J Captured Catchment Area

This appendix and figure 33 provide data of the division of the catchment area by the check

dam.

Figure 33 Captured Catchment Area by Check Dam

The total catchment area of the Cilalawi River is 72,06 km2 (A), while the total number of

squares is 221 (ntot) to make assumptions about the sub-watershed created by the check

dam. 7 squares (nc) at level check dam divided into downstream and upstream section.

49

58 squares at the downstream (nd) check dam generates the sub watershed of:

149 squares at the upstream (nu) check dam generates the sub watershed of:

Ad=

nd+ n

c2( )

ntot

!

"#

$

%&'A =

58+ 7 2( )221

!

"#

$

%&' 72.06 = 21.2 km

2 (29%)

Ad=

nu+ n

c2( )

ntot

!

"#

$

%&'A =

156+ 7 2( )221

!

"#

$

%&' 72.06 = 50.9 km

2 (71%)

50

Appendix K Precipitation Cisomang

This appendix provides precipitation data of the Cisomang, which will be used for the rational

method in the Cilalawi River watershed. The translation for the precipitation over the years is

given in table 20.

Bahasa Indonesia English

Tahun Data Year of Data

Tanggal Date

Bulan Months

Tahunan Annual

Hujan Maksimum Maximum Rain

Jml Curah Hujan Rainfall Amount

Jml. Hari Hujan Quantity Rainy Daily

Rata-rata Average

Hujan (1-15) Rain (1-15)

Jml. Data Kosong Quantity Data Empty

Hujan (16-31) Rain (16-31)

Jml. Data Kosong Quantity Data Empty Table 20 Translation Precipitation Bahasa Indonesia to English

Average precipitation is calculated in table 21 for 9 years. The tables 22 to 30 were used to

determine the total average.

Year Days Total Precipitation (mm/year) Average Precipitation (mm/h)

2001 365 2444 0.28

2002 364 2873 0.33

2003 365 2201 0.25

2004 366 2311 0.26

2005 365 2877 0.33

2006 365 2877 0.33

2007 365 2535 0.29

2008 366 2546 0.29

2009 365 2565 0.29

Average JOMN KDJP

Table 21 Average Precipitation Data of Cisomang Watershed

TAHUN DATA 2001

Tanggal BULAN Tahunan Jan Peb Mar Apr Mei Jun Jul Agt Sep Okt Nov Des

1 0 0 13,2 2,3 0 0 0 0 12 0 0 0

2 0 0 0 0 22,6 0 0 0 0 46,2 12,2 0

3 0 0 0 6,2 20,1 0 0 0 82,6 15,6 3 0

4 0 0 0 26 2 0 0 22 74,2 35,6 10,1 16,6

5 0 0 0 53,4 10,5 0 0 24,4 6,7 0 8,1 0

6 0 0 0 4 47,4 0 0 0 7 0 33,3 0

7 0 20,2 0 0 0 0 0 0 12,9 15 60,1 0

8 0 15 0 0 0 0 0 0 0 5,4 0 0

9 0 22 0 7 0 0 0 0 12,9 8,4 4,3 0

10 0 0 20,4 7,1 0 0 0 59 0 0 43,2 0

11 0 6 5 5,7 0 0 7 0 0 0 13,7 0

12 0 0 25,5 0 0 0 4 0 0 0 0 0

13 0 0 0 0 0 0 6 0 0 0 0 0

14 0 0 15,7 55 0 0 0 0 0 0 19,2 0

15 0 6,2 0 22,2 0 0 0 0 0 14 94 0

16 0 18 33,2 0 0 0 0 0 0 12,7 18,4 0

17 0 2,4 60 8 0 0 0 0 0 30 86,8 0

18 0 4 17,6 7 0 0 3,2 0 0 0 17,1 0

19 0 0 12 0 0 0 25,6 0 24,6 15,6 12 40,5

20 0 0 0 0 0 0 0 0 0 0 4,4 2,8

21 0 0 0 0 0 0 30 0 0 0 19 53

22 0 0 12 0 0 0 0 0 0 15,7 15,2 0

23 0 0 0 0 16,3 0 0 0 0 21,3 2,6 0

24 0 16 24,4 0 8,2 0 0 0 12,4 82,6 7,6 0

25 0 0 5,4 0 0 0 0 0 0 2,7 59 0

26 0 14,3 0 13 0 0 31,2 0 0 7,7 1,1 20

27 0 0 38,2 0 0 0 31,6 0 21,4 8,6 0 16

28 0 18,2 8,2 6,9 0 0 0 0 0 10 11,6 0

29 0 19,4 0 0 0 0 0 0 8,7 26,1 17

30 0 0 0 0 0 3,4 0 0 0 0 0

31 0 0 3,5 0 0 1,6 17,3

Hujan Maksimum 0 22 60 55 47 0 32 59 83 83 94 53 94

Jml Curah Hujan 0 142 310 224 131 0 142 105 267 357 582 183 2444

Jml. Hari Hujan 0 11 15 14 8 0 9 3 10 19 24 8 121

Rata-rata 0 5 10 7 4 0 5 4 9 12 19 6

Hujan (1-15) 0 69 80 189 103 0 17 105 208 140 301 17

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 0 73 230 35 28 0 125 0 58 217 281 167

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Table 22 Precipitation 2001

52

TAHUN DATA 2002


1 0 0 49 33,5 0 0 0 0 0 0 0 0

2 34,4 0 0 0 0 0 0 0 0 0 0 0

3 0 0 0 24 0 0 0 0 0 0 0 0

4 0 0 0 0 0 20 0 0 0 0 0 12,3

5 0 0 24,5 0 0 2,5 0 0 0 0 34,7 0

6 0 14 16 0 35,4 0 0 0 0 0 0 13,7

7 4,4 3,5 0 0 0 0 0 0 0 4,3 0 0

8 4,4 0 0 37 26,3 0 0 8,9 0 0 13 87,6

9 49,4 33,4 14,4 4,2 46,8 0 20 0 0 0 0 14,3

10 21,5 6,8 0 4,8 4,6 0 0 0 0 0 3,4 1,7

11 39,4 9 14,6 4,8 0 0 0 0 0 0 8,4 8,3

12 11 0 1,3 0 0 0 0 0 0 0 0 23

13 13,4 57,3 18,4 16,4 0 32,4 0 0 0 0 10 27,3

14 0 2 0 0 0 0 0 0 0 0 23,3 6,5

15 1,6 27 0 3,1 55,6 0 60 0 0 0 2,3 46,7

16 0 0 30 35 2,1 24,7 0 0 0 0 0 36,7

17 0 0 17,8 1,8 52 0 0 0 0 0 0 46,7

18 26,6 0 0 2,8 0 0 0 0 0 0 0 0

19 75,6 0 0 67 0 0 0 0 0 0 34 0

20 11 1,8 2 5,4 0 0 0 0 0 0 50,0 0

21 6,5 48,8 21 33,1 0 0 0 38 0 0 41 0

22 22 0 0 4,2 0 22,7 0 0 0 0 13,3 48,9

23 53,8 1,7 0 0 0 0 0 0 0 0 2,0 7,9

24 5,2 0 46,7 7 0 0 0 0 0 0 18,3 20

25 17,8 5,6 15,2 0 0 0 0 0 0 0 6 7,3

26 0 0 8,2 0 0 0 0 0 0 0 63,0 11,3

27 19,4 0 6,5 0 0 0 0 0 0 6,9 1,3

28 9 22,6 53 0 0 0 0 0 28 21 81,7 24,2

29 34,8 2,3 0 0 0 0 0 0 6,3 0,0 0

30 84,4 52 0 0 0 0 0 0 0 0 0

31 38,4 10 0 0 0 0 1,1

Hujan Maksimum 84,4 57,3 53 67,0 55,6 32,4 60 38 28 21 81,7 87,6 87,6

Jml Curah Hujan 584,0 233,5 402,9 284,1 222,8 102,3 80 46,9 28 38,5 403,4 446,8 2873,2

Jml. Hari Hujan 22 13 19 16 7 5 2 2 1 4 16 20 127

Rata-rata 18,8 8,3 13 9,5 7,2 3,4 2,7 1,6 0,9 1,3 13,4 14,4

Hujan (1-15) 179,5 153,0 138,2 127,8 168,7 54,9 80 8,9 0 4,3 94,6 241,4

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 404,5 80,5 264,7 156,3 54,1 47,4 0 38 28 34,2 308,8 205,4

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


53

TAHUN DATA 2003


1 0 23 0 4,3 53 0 0 0 0 0 0 23

2 0,0 24 46 0 2 0 0 0 0 0 2 21

3 2 2 0 18 0 0 0 0 0 0 2 0

4 2 20 0 0 0 0 0 0 0 2 41 67,0

5 0 22 0,0 14 0 0,0 0 0 0 11 3,3 0

6 0 0 16 0 2,0 7 0 0 9 15 6 24,0

7 0,0 0,0 11 0 3 0 0 0 0 25,1 0 23

8 0,0 35 6 0 25,3 0 0 0,0 0 10 0 48,6

9 38,2 0,0 7,1 0,0 0,0 0 0 0 0 16 0 0,0

10 9,2 0,0 4 52,2 0,0 0 0 0 0 0 0,0 0,0

11 0,0 7 0,0 6,2 0 0 0 0 0 23 0,0 48,9

12 0 9 1,5 1 0 0 0 0 0 79 0 51

13 0,0 0,0 0,0 3,3 33 0,0 0 0 0 3 0 15,5

14 0 0 12 28 39 0 0 0 21 0 0,0 3,2

15 37,3 57 0 0,0 62,7 0 0 0 30 0 27,1 0,0

16 0 14 0 0 3,7 0,0 0 0 59 4 5 2,0

17 0 15 4,6 0,0 0 0 0 2 40 23 0 7,7

18 0,0 17 2 2,7 0 0 0 0 0 0 0 0

19 0,0 0 3 4 0 4 0 0 78 0 9 2

20 0 0,0 0 0,0 4 0 0 0 3 0 4,6 0

21 0,0 0,0 0 9,0 0 0 0 0 13 0 0 8

22 0 0 5 0,0 0 0,0 0 0 0 0 0,0 0,0

23 31,0 15,0 6 2 0 8 0 0 0 0 6,7 8,0

24 0,0 0 0,0 11 0 0 0 0 0 0 69,8 0

25 69,0 0,0 7,8 0 0 0 0 0 0 21 9 0,0

26 47 0 3,7 0 1 0 0 0 0 0 3,8 5,2

27 0,0 0 0,0 0 0 0 0 0 0 0,0 6 0,0

28 14 0,0 2 0 0 0 0 0 0 0 0,0 0,0

29 0,0 - 0,0 3 0 0 0 0 0 0,0 0,0 0

30 0,0 - 0 8 0 0 0 3 0 23 0 0

31 20,0 - 2 - 0 0 0 0 - 51 0 0,0

Hujan Maksimum 69,0 57,4 46 52,2 62,7 8,3 0 3 78 79 69,8 67,0 79,0

Jml Curah Hujan 269,8 259,7 139,3 166,1 228,8 19,2 0 5,2 254 306,4 194,2 358,3 2200,9

Jml. Hari Hujan 10 13 17 15 11 3 0 2 8 14 14 16 123

Rata-rata 8,7 9,3 4 5,5 7,4 0,6 0,0 0,2 8,5 10,2 6,5 11,6

Hujan (1-15) 89,0 199,1 102,9 126,3 220,3 6,8 0 0,0 61 184,2 80,8 325,4

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 180,8 60,6 36,4 39,8 8,5 12,4 0 5 193 122,2 113,4 32,9

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


54

TAHUN DATA 2004


1 5 0 0 25,0 8 0 0 0 0 0 0 0

2 0,0 0 0 0 0 0 0 0 0 0 0 0

3 0 33 77 0 16 0 0 0 0 0 0 0

4 15 0 48 30 0 0 4 0 2 0 0 0,0

5 5 3 2,0 0 80 0,0 0 0 3 6 0,0 0

6 5 17 0 0 80,4 10 0 0 0 0 32 0,0

7 0,0 13,7 0 5 0 0 0 0 0 0,0 28 0

8 0,0 0 0 14 0,0 7 0 0,0 0 0 35 43,0

9 0,0 9,8 0,0 36,0 5,0 7 11 0 0 14 0 0,0

10 9,7 0,0 0 0,0 7,0 0 0 0 0 0 3,4 20,0

11 0,0 0 14,6 2,3 11 0 2 0 0 0 0,0 38,2

12 30 14 68,2 0 0 0 17 0 0 0 0 0

13 19,0 30,0 0,0 0,0 0 0,0 6 0 0 0 0 0,0

14 0 0 0 4 9 0 6 74 0 0 4,0 9,0

15 0,0 15 0 0,0 4,7 0 21 0 0 0 17,6 15,0

16 0 27 42 21 8,0 0,0 0 0 0 0 15 10,0

17 35 3 0,0 5,0 0 0 0 0 0 0 3 39,0

18 12,0 0 0 0,0 20 0 0 0 0 4 3 47

19 39,9 14 7 0 0 0 0 0 0 0 3 28

20 0 0,0 0 20,0 7 0 0 0 0 0 0,0 0

21 12,7 4,6 17 40,6 0 1 0 0 0 7 2 2

22 0 0 0 0,0 0 8,0 0 0 0 0 30,6 9,8

23 22,2 4,2 0 0 12 0 0 0 0 1 16,6 1,2

24 5,7 3 15,8 0 0 1 0 0 0 19 1,0 19

25 0,0 21,0 0,0 17 0 0 0 0 0 0 0 0,0

26 5 26 0,0 0 18 3 0 0 0 0 22,0 19,8

27 0,0 14 0,0 0 0 0 0 0 14 0,0 19 22,8

28 0 0,0 0 20 0 0 0 0 0 0 9,0 1,9

29 0,0 0 16,0 2 1 0 0 0 2 0,0 14,6 0

30 4,1 - 0 70 0 0 0 0 34 0 25 19

31 4,1 - 0 - 1 - 0 0 - 0 - 12,5

Hujan Maksimum 39,9 33,0 77 70,2 80,4 10,0 21 74 34 19 35,0 47,4 80,4

Jml Curah Hujan 230,9 252,4 306,5 312,4 287,7 36,1 67 74,0 55 50,4 282,0 356,9 2311,3

Jml. Hari Hujan 16 17 10 15 16 7 7 1 5 6 19 18 137

Rata-rata 7,4 9,0 10 10,4 9,3 1,2 2,2 2,5 1,8 1,7 9,4 11,5

Hujan (1-15) 89,6 135,3 209,1 116,9 220,7 23,6 67 74,0 5 19,7 120,3 125,2

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 141,3 117,1 97,4 195,5 67,0 12,5 0 0 50 30,7 161,7 231,7

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


55

TAHUN DATA 2005


1 0 56 4 3,2 0 0 16 32 0 0 47 14

2 0,0 0 0 0 0 0 0 0 0 0 24 8

3 0 0 22 5 0 5 0 0 0 0 0 0

4 11 28 14 25 0 0 0 0 0 0 13 6,6

5 7 18 13,5 0 2 0,0 0 0 0 0 8,9 55

6 40 13 19 0 5,4 0 0 0 0 0 16 0,0

7 1,5 0,0 25 33 0 0 0 0 0 0,0 0 2

8 38,3 0 0 16 34,0 0 0 0,0 0 0 0 14,6

9 14,7 0,0 0,0 9,7 0,0 0 0 0 0 0 0 11,6

10 0,0 0,0 0 32,7 0,0 0 0 0 0 0 75,4 43,0

11 10,5 3 2,0 5,0 0 0 4 14 8 0 0,0 2,0

12 2 7 4,3 9 25 23 20 10 0 48 0 0

13 0,0 6,5 19,0 0,0 0 4,0 2 0 5 15 9 15,0

14 27 2 3 32 0 0 0 0 0 0 0,0 0,0

15 8,6 0 0 1,0 17,0 55 0 0 0 9 0,0 0,0

16 53 18 0 0 1,4 0,0 21 0 0 0 0 0,0

17 29 15 15,7 45,8 0 0 5 0 0 12 2 11,0

18 31,2 46 0 6,8 0 0 0 0 36 6 0 9

19 1,7 32 67 9 0 0 0 0 0 14 0 2

20 25 28,9 0 0,0 0 0 0 0 6 0 71,3 1

21 0,0 0,0 5 1,0 0 7 0 48 11 0 0 0

22 0 74 27 0,0 0 23,6 0 0 0 5 8,6 0,0

23 9,3 63,5 14 0 0 0 0 0 0 80 3,6 16,7

24 25,6 1 0,0 0 0 22 0 0 19 0 11,5 0

25 0,0 13,3 14,4 0 0 0 0 0 0 0 8 0,0

26 0 4 0,0 0 0 0 0 0 0 19 0,0 15,8

27 0,0 2 4,0 0 0 0 0 66 0 16,4 0 0,0

28 2 4,0 39 0 0 6 0 3 0 0 59,3 0,0

29 3,3 - 11,0 0 0 3 0 0 0 0,0 64,8 22

30 0,0 - 43 0 0 4 0 0 29 0 0 9

31 0,0 - 7 - 0 - 0 0 - 0 - 0,0

Hujan Maksimum 52,6 73,9 67 45,8 34,0 55,4 21 66 36 80 75,4 55,4 79,5

Jml Curah Hujan 340,9 435,4 371,6 233,4 85,6 151,0 67 173,9 113 223,9 423,0 258,6 2876,9

Jml. Hari Hujan 19 20 21 15 6 10 6 6 7 10 15 18 153

Rata-rata 11,0 15,6 12 7,8 2,8 5,0 2,2 5,8 3,8 7,5 14,1 8,3

Hujan (1-15) 161,3 133,5 126,0 170,6 84,2 86,8 41 56,4 13 72,6 193,6 172,6

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 179,6 301,9 245,6 62,8 1,4 64,2 26 118 100 151,3 229,4 86,0

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


56

TAHUN DATA 2006


1 0 56 4 3,2 0 0 16 32 0 0 47 14

2 0,0 0 0 0 0 0 0 0 0 0 24 8

3 0 0 22 5 0 5 0 0 0 0 0 0

4 11 28 14 25 0 0 0 0 0 0 13 6,6

5 7 18 13,5 0 2 0,0 0 0 0 0 8,9 55

6 40 13 19 0 5,4 0 0 0 0 0 16 0,0

7 1,5 0,0 25 33 0 0 0 0 0 0,0 0 2

8 38,3 0 0 16 34,0 0 0 0,0 0 0 0 14,6

9 14,7 0,0 0,0 9,7 0,0 0 0 0 0 0 0 11,6

10 0,0 0,0 0 32,7 0,0 0 0 0 0 0 75,4 43,0

11 10,5 3 2,0 5,0 0 0 4 14 8 0 0,0 2,0

12 2 7 4,3 9 25 23 20 10 0 48 0 0

13 0,0 6,5 19,0 0,0 0 4,0 2 0 5 15 9 15,0

14 27 2 3 32 0 0 0 0 0 0 0,0 0,0

15 8,6 0 0 1,0 17,0 55 0 0 0 9 0,0 0,0

16 53 18 0 0 1,4 0,0 21 0 0 0 0 0,0

17 29 15 15,7 45,8 0 0 5 0 0 12 2 11,0

18 31,2 46 0 6,8 0 0 0 0 36 6 0 9

19 1,7 32 67 9 0 0 0 0 0 14 0 2

20 25 28,9 0 0,0 0 0 0 0 6 0 71,3 1

21 0,0 0,0 5 1,0 0 7 0 48 11 0 0 0

22 0 74 27 0,0 0 23,6 0 0 0 5 8,6 0,0

23 9,3 63,5 14 0 0 0 0 0 0 80 3,6 16,7

24 25,6 1 0,0 0 0 22 0 0 19 0 11,5 0

25 0,0 13,3 14,4 0 0 0 0 0 0 0 8 0,0

26 0 4 0,0 0 0 0 0 0 0 19 0,0 15,8

27 0,0 2 4,0 0 0 0 0 66 0 16,4 0 0,0

28 2 4,0 39 0 0 6 0 3 0 0 59,3 0,0

29 3,3 - 11,0 0 0 3 0 0 0 0,0 64,8 22

30 0,0 - 43 0 0 4 0 0 29 0 0 9

31 0,0 - 7 - 0 - 0 0 - 0 - 0,0

Hujan Maksimum 52,6 73,9 67 45,8 34,0 55,4 21 66 36 80 75,4 55,4 79,5

Jml Curah Hujan 340,

9

435,4 371,6 233,4 85,6 151,0 67 173,9 113 223,9 423,0 258,6 2876,9

Jml. Hari Hujan 19 20 21 15 6 10 6 6 7 10 15 18 153

Rata-rata 11,0 15,6 12 7,8 2,8 5,0 2,2 5,8 3,8 7,5 14,1 8,3

Hujan (1-15) 161,

3

133,5 126,0 170,6 84,2 86,8 41 56,4 13 72,6 193,6 172,6

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 179,

6

301,9 245,6 62,8 1,4 64,2 26 118 100 151,3 229,4 86,0

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


57

TAHUN DATA 2007


1 0 8 0 0,0 0 3 0 0 0 0 7 12

2 0,0 4 0 15 0 6 34 0 0 0 3 0

3 0 1 0 5 47 0 0 0 0 0 1 0

4 0 40 0 25 0 0 0 0 0 0 14 28,0

5 0 5 0,0 2 0 1,9 0 0 0 0 10,5 12

6 0 0 0 0 36,4 11 0 0 0 0 12 15,9

7 0,0 0,0 0 0 0 0 0 0 0 0,0 11 9

8 0,0 0 0 5 0,0 16 0 0,0 3 15 12 0,0

9 0,0 0,0 0,0 6,6 25,5 0 0 0 0 6 71 0,0

10 0,0 0,0 0 0,0 0,0 17 0 0 0 6 61,5 0,0

11 0,0 2 0,0 9,4 4 0 0 0 0 0 140,0 83,8

12 0 35 0,0 8 0 0 0 0 0 0 50 9

13 0,0 47,0 0,0 11,0 0 0,0 0 0 0 0 11 1,0

14 16 6 0 59 0 0 0 0 0 12 30,3 86,0

15 0,0 21 0 5,0 1,0 7 0 0 1 5 40,0 8,8

16 0 15 0 0 0,0 0,0 0 0 0 0 0 37,0

17 0 3 0,0 3,0 2 0 0 0 0 0 0 0,0

18 0,0 15 0 4,3 1 0 0 0 0 0 0 0

19 0,0 27 0 38 2 13 0 0 0 0 0 88

20 0 53,0 0 66,0 0 1 0 0 0 0 0,0 5

21 0,0 12,0 0 15,0 0 28 0 3 0 0 0 6

22 16 11 0 5,5 0 0,0 0 0 0 34 0,0 3,4

23 6,0 17,0 0 20 16 18 0 0 0 0 13,8 0,0

24 0,0 0 0,0 5 0 0 0 0 0 57 0,0 0

25 27,0 16,0 0,0 84 0 0 0 0 1 0 0 8,9

26 9 15 0,0 52 0 0 0 16 0 0 16,7 0,0

27 14,0 0 0,0 33 0 0 0 0 0 17,7 22 0,0

28 13 0,0 0 10 0 9 0 0 0 0 0,0 2,9

29 8,0 - 0,0 8 0 0 0 0 0 0,0 6,7 3

30 2,0 - 0 82 0 0 0 0 0 56 0 0

31 14,0 - 0 - 0 - 0 0 - 1 - 0,0

Hujan Maksimum 27,0 53,0 0 84,0 46,8 27,8 34 16 3 57 140,0 87,9 140,0


0

353,0 0,0 575,1 134,7 130,8 34 18,5 5 209,8 531,2 418,4 2535,0

Jml. Hari Hujan 10 20 0 25 9 12 1 2 3 10 19 18 129

Rata-rata 4,0 12,6 0 19,2 4,3 4,4 1,1 0,6 0,2 7,0 17,7 13,5

Hujan (1-15) 16,0 169,0 0,0 151,0 113,6 62,0 34 0,0 3 43,9 472,5 264,8

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 109,

0

184,0 0,0 424,1 21,1 68,8 0 19 1 165,9 58,7 153,6

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


58

TAHUN DATA 2008


1 38 13 0 1,4 10 4 0 0 7 0 15 3

2 68,3 7 22 4 30 0 0 0 0 1 1 87

3 17 12 9 2 0 0 0 0 0 0 43 17

4 11 0 5 0 1 0 0 0 0 0 11 6,5

5 2 0 0,0 0 19 1,2 0 0 0 8 3,9 20

6 0 0 8 0 12,5 0 0 0 0 0 18 15,2

7 13,3 0,0 3 0 7 0 0 0 0 0,0 31 4

8 0,0 4 4 20 19,3 0 0 0,0 11 3 0 5,5

9 0,0 3,5 0,0 0,0 0,0 0 0 0 0 26 12 0,0

10 0,0 0,0 33 6,8 1,3 0 0 0 0 0 37,2 0,0

11 0,0 23 47,3 0,0 3 46 0 0 26 0 14,4 5,5

12 0 0 5,4 8 0 0 0 12 0 0 0 0

13 0,0 6,0 35,0 24,8 0 17,0 0 0 0 0 20 0,0

14 0 15 39 0 0 0 0 6 0 0 45,8 0,0

15 0,0 0 0 3,1 0,0 0 0 0 0 0 15,9 33,5

16 6 0 70 0 0,0 0,0 0 0 0 0 40 2,9

17 0 3 1,7 0,0 0 0 0 0 12 0 121 0,0

18 0,0 2 59 22,8 0 0 0 0 0 1 0 0

19 0,0 11 9 0 0 0 0 0 0 0 4 0

20 0 3,8 22 90,9 0 0 0 0 0 0 7,3 0

21 0,0 7,6 0 11,0 0 0 0 0 0 0 1 0

22 2 8 0 9,5 0 0,0 0 0 0 0 3,4 5,5

23 13,3 0,0 41 31 0 0 0 0 0 0 0,0 17,9

24 0,0 0 0,0 0 0 0 0 0 0 15 110,4 4

25 2,6 5,2 23,8 0 0 0 0 0 0 0 0 0,0

26 25 2 0,0 0 0 0 0 0 0 0 0,0 0,0

27 12,0 0 0,0 0 0 0 0 0 0 1,0 0 0,0

28 29 5,6 2 0 0 0 0 0 0 1 7,5 2,3

29 1,5 0 0,0 0 0 0 0 67 0 90,5 0,0 0

30 0,0 - 0 6 0 0 0 0 0 17 21 0

31 5,5 - 34 - 0 - 0 173 - 0 - 0,0

Hujan Maksimum 68,3 22,9 70 90,9 30,0 46,0 0 173 26 91 120,5 86,8 173,0


4

129,8 472,4 239,0 101,7 67,9 0 257,2 56 164,7 582,5 228,9 2546,3

Jml. Hari Hujan 15 17 20 14 9 4 0 4 4 10 22 15 134

Rata-rata 7,9 4,6 15 8,0 3,3 2,3 0,0 8,6 1,9 5,5 19,4 7,4

Hujan (1-15) 150,

2

82,9 209,4 68,8 101,7 67,9 0 17,2 44 38,6 268,1 196,5

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 96,2 46,9 263,0 170,2 0,0 0,0 0 240 12 126,1 314,4 32,4

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


59

TAHUN DATA 2009


1 0 2 9 0,0 68 0 0 0 0 0 4 19

2 0,0 31 0 42 5 0 0 0 15 22 0 0

3 0 4 0 0 0 56 0 0 0 0 0 14

4 0 16 5 55 21 70 0 0 0 0 0 0,0

5 0 1 34,9 0 0 2,5 0 0 0 162 0,0 7

6 0 6 24 3 0,0 0 0 0 13 42 0 32,5

7 0,0 8,7 0 12 6 0 0 0 0 12,0 0 1

8 0,0 0 0 21 1,3 0 0 0,0 0 3 0 23,5

9 21,4 12,2 2,0 5,0 4,5 14 0 0 0 0 0 0,0

10 0,0 19,5 0 0,0 0,0 0 0 0 0 0 0,0 30,0

11 0,0 2 25,0 0,0 0 4 0 0 11 0 3,4 66,5

12 2 23 0,0 0 8 0 0 0 0 0 39 0

13 15,5 1,0 21,5 0,0 0 0,0 0 0 0 0 4 0,0

14 52 0 0 55 0 0 0 0 0 48 62,0 0,0

15 49,5 0 0 0,0 8,1 3 0 0 0 51 0,0 0,0

16 9 0 0 0 0,0 0,0 0 0 0 0 4 0,0

17 9 5 0,0 0,0 0 0 0 0 64 0 12 41,5

18 6,3 3 0 0,0 9 0 0 15 11 10 82 0

19 0,0 0 0 0 8 0 0 0 0 0 27 0

20 28 21,7 8 66,0 0 0 0 0 5 0 50,0 0

21 0,0 15,3 0 0,0 118 0 0 0 0 0 143 0

22 0 53 0 23,0 3 0,0 0 0 0 32 15,5 0,0

23 0,0 6,1 10 6 2 0 0 0 1 0 5,5 0,0

24 0,0 20 0,0 69 0 37 0 0 0 0 0,0 0

25 22,4 2,0 0,0 0 0 0 59 0 63 0 0 0,0

26 14 0 25,0 27 0 0 4 0 58 0 5,5 163,5

27 50,4 0 9,0 9 0 0 0 0 0 27,0 65 23,0

28 0 4,0 7 6 0 0 0 0 0 2 3,5 39,0

29 17,7 - 0,0 0 0 0 0 0 0 92,5 0,0 2

30 31,5 - 22 0 11 16 0 0 22 0 41 0

31 2,8 - 0 - 0 - 0 0 - 0 - 44,5

Hujan Maksimum 52,3 53,0 35 69,0 118,0 70,3 59 15 64 162 142,5 163,5 163,5

Jml Curah Hujan 332,4 254,7 200,6 396,8 269,6 201,7 63 15,0 260 501,5 564,9 505,0 3565,2

Jml. Hari Hujan 15 21 13 14 14 8 2 1 10 12 17 14 141

Rata-rata 10,7 9,1 6 13,2 8,7 6,7 2,1 0,5 8,7 16,7 18,8 16,3

Hujan (1-15) 141,0 125,0 119,9 191,8 120,3 149,2 0 0,0 38 339,0 112,4 192,0

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0

Hujan (16-31) 191,4 129,7 80,7 205,0 149,3 52,5 63 15 223 162,5 452,5 313,0

Jml. Data Kosong 0 0 0 0 0 0 0 0 0 0 0 0


Appendix L Land Runoff Formula

The rational formula consists of the q as discharge (m3/s), the empirical constant 0.0028, the

c as coefficient of runoff (-), the i for rainfall (mm/h) and A for the watershed surface (ha). The

rational formula is in the next step combined with sediment in the derived runoff. This tool is

normally used for watershed surface area of 800 ha or smaller.

q = 0.0028ciA

The used average precipitation in i is 0.29 mm/h (Appendix K). The parameter c with A is

divided in 3 kinds of land use (minimum precipitation of 25 mm/h). For instance, precipitation

data of 2010 does not show rainfall higher than 100 mm/h. The values are mostly around 25

mm/h. The outcome of 3 land types, the coefficients A and c are shown in table 31.

Land Type Percentage (%) A (ha) Cover & Hydrologic Condition c (-) cA (-)

Barren 15 765 Bare, poor practice 0.8 612

Cultivated 70 3570 Row crop, good practice 0.47 1678

Forest 15 765 Woodland 0.02 15

Total 2305 Table 31 Land Type Surface and Runoff Coefficient

The surface is calculated by the percentage for the land type of the sub-watershed area of

5100 ha (= 51 km2). The cover & hydrologic conditions and c-values partly come from the

rational method, described by Schwab et al. [1983]. For example, the Chézy coefficient in the

land type barren is assumed to be 0.8, because buildings, roads and sandy paths occupy

this surface. This lead to the calculation of the discharge on land.

q = 0.0028cAi = 0.0028 !2305 !0.29 =1.87 m3

/ s

The discharge by rainfall is almost three smaller than the average discharge in the river of

5.54 m3/s from (Appendix P), used for the sediment transport. These values should be at

least the same considering that the amount of water is higher rainfall, because normally

water is partly stored in the underground. Difference occurs due to the formula for an 800 ha

watershed, rainfall of Cisomang watershed, an empirical sediment transport concentration

and global land conditions.

The Qsed is the amount of sediment per unit of time (kg/s) with csed (kg/m3). csed is the

sediment transport concentration of 9.7 kg/m3 based on the watershed of the nearby

Cisomang [Fakultas Teknologi Industri Pertanian, Universitas Padjadjaran, 2009].

Qsed = qcsed =1.87 !9.70 =18.14 kg/s

The amount of sediment of land in the river (Qvsed) is given in years (seconds, minutes,

hours/day, days/year):

Qvsed =Qsedt

!w=

18.14 ! (60 !60 !24 !365)

1973= 289946 m3 /year

The calculated 300 thousand m3/year is approximately 2% of the 13.6 million m3/year of the

Cilalawi River sediment. These amount could be three times or more on the grounds that of

high uncertainty in the used formula and data.

61

Appendix M Parameter List

Parameter Description Unit

A Surface m2

b Width m

C Chézy coefficient m1/2/s

Fr Froude number -

g Gravitation m/s2

h Water depth m

H Specific energy m

i Gradient m/m

k Wall Rougness m

Q Discharge m3/s

R Hydraulic radius m

Re Reynolds number -

s Bed transport m3/s/m

v Flow velocity m/s

! Viscosity m2/s Table 32 Parameter List and Units

62

Appendix N River Profile

The river profile (wet and dry) at the location of the check dam is measured during the survey.

This is the profile that gives the width for the model and check dam design. There are larger

and smaller widths to be found in other sections of the river down- and upstream. The river

structure will be similar to the other three points in the upstream (Chapter 6) by making this

profile a rectangle for calculations.

The necessary equipment for this survey is two jalon of 2 m and 3 m, and one

polysan of 30 m. The polysan is strained above the river with marks of red tape every single

meter. With the jalon the height is measured from the polysan to the bed. The result is the

next river profile (figure 34).

Figure 34 River Profile of Cilalawi River

The values are given in table 33. The water level en wet profile starts at the depth (h) of 3.75

m from the height, where inundation takes place when water rise above line. The most used

surface of the river is estimated to be between point 4 and 17 (13 m) from visiting the

location, assuming this will be where the average discharges are, because there is no

vegetation to be found on this surface area.

A schematic presentation of this river profile is a rectangle. The width of the

measured wet profile is between point 14 and 8 (6 m).

Averaged with the average width of 13 m the width of this schematic rectangle is

assumed to be equivalent to 10 m. The residual of wet circumference is partly occupied by

the rectangle height. The maximum water depth (hmax) is, from the figure, 5.15 m. This

number is used for the check dam design.

Point Height (m) Water Level (m)

0 0.00 0

1 0.90 0

2 1.90 0

3 2.30 0

4 2.70 0

5 3.10 0

6 3.40 0

7 3.50 0

8 3.75 0

9 4.10 0.35

10 5.15 1.40

11 5.00 1.25

12 4.20 0.45

63

13 4.00 0.25

14 3.85 0.1

15 3.75 0

16 3.60 0

17 3.00 0

18 2.70 0

19 2.80 0

20 2.60 0

21 0.70 0

22 0.20 0

22.4 0.00 0 Table 33 Measurements River Profile

64

Appendix O Flow Velocity

Knowledge of the current stream is required to make the first estimation of the Chézy

coefficient for the sediment transport model. Therefore, a current meter is used to see the

flow velocity in the wet river profile (figure 35). With a better look it can be seen that this is

the lowest part of the profile in figure 34. The height and surface area for each point is given

in table 34. The nine flow velocities in this profile are shown in table 35.

Figure 35 Flow Velocities in River Profile

Point Height (m) Surface Area (m2)

0 0.00 !"#$%%

1 0.35 !"$$%%

2 1.40 #"&&%%

3 1.25 !"$'%%

4 0.45 !"&'%%

5 0.25 !"#$%%

6 0.10 !"!'%%

7 0.00 !"#$%%

Total ! "#$%!

Table 34 Measurements River Profile with Water

Point Flow Velocity (m/s)

A 0.30

B 0.20

C 0.15

D 1.30

E 1.00

F 0.80

G 0.90

H 0.35

I 0.10

Average 0.55 Table 35 Flow Velocities During Survey

65

The width (bw) of the schematic rectangle profile is designed to be 4 m, because that is

where the majority of the stream is. This results in the surface area (Aw) for the section.

Aw= h

wbw

! hw=Aw

bw

=3.80

4.00= 0.95 m

This leads to the data for the profile filled with water, including the water depth (hw), the

average flow velocity (vw) and the associated discharge (Qw).

Aw = 3.80 m2

bw = 4.00 m

hw = 0.95 m

vw = 0.55 m/s

Qw = Awvw = 3.80 !0.55= 2.10 m3

/ s

With the previous variables the Reynolds number can be calculated. The Reynolds number

will indicate turbulent and laminar water flow. The hydraulic radius (R) is used with the

viscosity (!) of water and the flow velocity. The water viscosity of 20°C water is 1.00e-6 m2/s

(30°C is the local temperature).

Rw=

hwbw

2hw+ b

w

=0.95 ! 4.00

2 !0.95+ 4.00= 0.64 m

Rew=vw!R

w

!=0.55 !0.64

1.00 !10"6= 352000

The Reynolds number is larger than 800, which means that the flow is turbulent. This will

cause disturbance on the riverbed and will set the sediment in motion.

66

Appendix P Discharges

The next data is derived from the PSDA checkpoint ±500 m downstream of the railway bridge.

Discharges data of the years 2000, 2001, 2002, 2005, 2006, 2007, 2008 and 2009 are

presented in the tables 37 to 43. The years 2003 are 2004 are lost in the archiving. The

average discharge is needed to make calculations for the sediment transport over the years

(table 36). The discharges are:

Years Averages Discharge (m3/s)

2000 ("$#%

2001 $"((%

2002 )"$'%

2005 &"*!%

2006 &"**%

2007 &"*)%

2008 +"((%

2009 +"$*%

2010 ##",%

Average &#&'!

Table 36 Average Discharges

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& !"#!$ %#&'$ &#"($ !)#)$ )#!*$ %#''$ (#+'$ (#+!$ &#+($ %#''$ '#!$ (#+!$

<& &#,%$ )#)%$ %#&($ !,#)$ %#&($ (#++$ (#(,$ %#"!$ %#&($ (#++$ !,#,$ (#(,$

)& %#%,$ )#'*$ !*#)$ !)#+$ !+$ (#,%$ (#%)$ %#),$ !*#)$ (#,%$ '#()$ %#),$

=& !*#!$ &#,+$ '#*$ !)#($ !"#%$ (#,!$ (#+!$ &#*+$ '#*$ (#,!$ !"#+$ &#*+$

>& '#+)$ !!$ !,#!$ !!#'$ !(#+$ *#&'$ )#"+$ %#'($ !,#!$ *#&'$ &#"($ %#'($

?& )#(*$ &#)%$ &#,&$ !%#%$ )#*+$ *#&!$ (#%*$ (#%*$ !*#)$ (#%,$ '#+)$ %#!+$

@& &#&!$ &#'($ ,*#&$ '#+!$ !%#+$ *#'*$ %#"!$ (#*$ )#"%$ *#'*$ '#'&$ (#*$

A& )#)&$ !!#+$ !%$ !"#%$ )#'*$ *#&*$ )#"%$ !,$ %#!%$ *#&*$ &#,+$ !,$

B& !"#($ )#!!$ )#+'$ !)#)$ '#+!$ *#&'$ %#!!$ !!$ (#*'$ *#&'$ )#"&$ !!#+$

;C& !"#%$ %#"'$ !"#,$ %#),$ !"#%$ %#'($ (#*+$ %#&$ (#*+$ %#'($ '#"!$ %#&$

;;& (#'!$ )#"%$ !+#%$ &#*%$ (#&%$ %#),$ %#)($ %#&+$ (#*+$ %#),$ '#,$ %#&+$

;<& %#%&$ '#)!$ %#&($ %#'($ )#&,$ %#*%$ %#,&$ '#"%$ (#*($ %#*%$ !"#*$ )#')$

;)& )#)%$ !"#($ (#'!$ (#%,$ '#+)$ %#+*$ (#&%$ '#+!$ (#(($ %#+*$ !+#!$ '#+!$

;=& (#&&$ '#!*$ %#&$ (#*$ %#&'$ %#(!$ (#(&$ )#"&$ (#(&$ %#(!$ !'#'$ )#"&$

;>& !!$ )#!)$ %#*%$ %#(*$ %#%*$ )#!!$ )#"%$ )#)$ (#*+$ %#&'$ '#%($ )#)%$

;?& !+#)$ '#+)$ %#,!$ !,$ )#*+$ %#'($ (#*+$ )#"!$ (#*+$ %#'($ !,#%$ )#"!$

;@& )#!*$ !"#!$ (#*+$ !!$ !"#'$ %#,&$ (#,&$ %#!+$ (#*($ %#,&$ !)#%$ %#!+$

;A& (#&&$ )#"%$ %#''$ '#,+$ '#!,$ (#(,$ %#',$ %#(*$ (#,&$ (#+'$ !+#%$ %#(*$

;B& %#&($ (#*($ (#*+$ %#&$ %#*!$ (#%&$ (#*+$ )#*%$ (#*+$ *#!+$ !"#)$ )#*%$

<C& )#++$ (#(,$ (#&&$ !(#+$ (#%)$ (#++$ (#&&$ )#"+$ !!#*$ (#++$ '#"!$ )#"%$

<;& %#&+$ %#'$ !!#&$ %#&+$ (#()$ (#(($ (#*+$ (#%)$ )#!&$ (#(($ )#')$ (#%)$

<<& !!#!$ (#'%$ )#"!$ )#)&$ (#++$ (#*$ (#'%$ (#(($ )#!!$ (#*$ )#!!$ (#(($

<)& &$ (#%,$ %#!'$ '#+!$ (#,&$ (#,%$ %#"'$ (#++$ %#+&$ (#,&$ )#)%$ (#++$

<=& !*#)$ %#%*$ &#"+$ )#"&$ (#*+$ (#+'$ (#($ (#'&$ (#%,$ (#++$ !!#,$ (#'&$

<>& !)#($ (#'&$ )#"!$ )#)$ (#(,$ (#&*$ (#*+$ %#',$ (#*+$ (#&%$ )#&'$ %#%&$

<?& '#)!$ (#!)$ &#',$ )#"!$ (#++$ (#($ (#'*$ (#*+$ (#+!$ (#($ )#*&$ (#*($

<@& '#"+$ (#*+$ %#&($ )#(&$ (#,&$ )#!!$ %#&+$ (#'&$ (#++$ !*$ &#"+$ (#&!$

<A& !"#+$ %#"'$ !"#)$ %#&+$ (#,&$ %#'($ %#!'$ %#!%$ (#*+$ ,%#%$ )#!&$ %#,%$

<B& !"#'$ )#&'$ )#(*$ )#)+$ (#+!$ %#,%$ (#++$ (#*$ (#*'$ ,!#($ '#"!$ (#)*$

)C& '#%'$ $ (#*'$ )#%,$ (#,&$ (#,%$ %#!!$ %#!+$ )#"%$ ,!#!$ (#*($ %#)($

);& !!#($ $ )#%,$ $ )#"%$ $ (#*($ )#'*$ $ &#&($ $ $Table 37 Discharges 2000

68

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& (#')$ '#%($ )#%&$ '#*)$ (#)!$ )#&($ %#!!$ *#&,$ (#)!$ '#+'$ !"#($ (#')$

<& (#&($ !!#&$ %#%'$ !"#*$ '#+'$ )#%!$ %#%$ %#+($ !"#*$ )#)'$ !!#'$ (#*)$

)& !!#*$ !(#&$ )#)'$ &#,)$ !!#'$ )#%!$ )#%&$ %#(,$ !+#,$ %#(,$ !*$ %#,)$

=& )#**$ &#(*$ !*#*$ !!#*$ )#"!$ (#)!$ %#&+$ %#%'$ !(#($ &#,)$ !*#*$ %#!!$

>& &#),$ '#*)$ !%#($ !"#%$ '#(%$ )#"!$ '#*)$ )#+($ !!#'$ &#(*$ &#(*$ %#"+$

?& )#(,$ %#&+$ )#%&$ '#+'$ !!#%$ '#*)$ )#'%$ %#%'$ !!#&$ '#%($ !"#,$ '#+$

@& )#&($ )#!'$ !+#($ '#,!$ '#)+$ '#!,$ )#(,$ '#+$ %#+($ )#%!$ !+$ !!#+$

A& )#+($ !!#($ !,#%$ !!#&$ %#"+$ !'#+$ '#!,$ )#'%$ )#'%$ )#,)$ !*#!$ )#)'$

B& &#*($ !%#%$ !*#'$ '#%($ )#**$ %#%'$ )#'%$ )#'%$ !!#($ '#)+$ '#*)$ (#&($

;C& )#"!$ &#,)$ !+#&$ '#*)$ )#&($ %#(,$ &#"&$ )#(,$ '#',$ )#**$ !,#!$ (#%,$

;;& )#(,$ )#%&$ !"#!$ )#'%$ '#%($ )#&($ )#'%$ '#*)$ '#"*$ %#'($ !,#)$ (#*)$

;<& %#%$ !(#)$ )#%!$ &#'!$ '#!,$ (#*)$ '#+'$ )#'%$ )#'%$ )#%!$ !*#+$ (#%,$

;)& '#)+$ !"#*$ '#+$ ,!#*$ !"#'$ (#')$ )#'%$ )#%!$ %#%'$ '#+'$ ,)#*$ )#%!$

;=& )#%!$ )#%&$ )#)'$ !*#%$ !,#!$ )#!$ )#%&$ )#!'$ %#!!$ !"#!$ !*#&$ )#**$

;>& )#+($ )#"!$ )#&($ &#,)$ !!#%$ (#')$ &#(*$ %#%'$ '#+$ !,#'$ !&#%$ %#&+$

;?& %#)%$ )#!'$ %#'($ !(#,$ )#%&$ (#%,$ )#%&$ %#!!$ )#%&$ &#+%$ !(#%$ )#(,$

;@& %#!!$ '#+'$ !+#%$ &#"&$ '#"*$ (#&($ '#!,$ (#%,$ '#)+$ )#%!$ ,"#)$ )#!$

;A& !(#!$ )#(,$ !&#&$ !+#)$ !,$ (#')$ !!#+$ (#,+$ )#%&$ '#*)$ ,"#)$ )#%&$

;B& '#!,$ %#,)$ !"#,$ )#'%$ !!#,$ (#%,$ )#)'$ ($ )#**$ !"#!$ ,!#*$ )#"!$

<C& '#,!$ (#')$ !"#($ )#**$ '#"*$ %#)%$ )#**$ (#)&$ '#',$ &#&$ !%#&$ %#"+$

<;& )#!$ )#%&$ )#%&$ !"#!$ '#+$ %#!&$ )#)'$ %#(,$ )#%!$ !,#%$ ,!#*$ %#(,$

<<& %#%$ !!#($ %#(,$ '#&!$ &$ (#)!$ )#+($ (#&($ '#"*$ &#(*$ !,#'$ '#,!$

<)& (#&($ )#+($ (#&($ )#&($ !'#+$ (#+!$ %#&+$ (#,+$ )#(,$ !,#,$ !*#&$ )#&($

<=& %#,)$ %#+($ %#*+$ (#(*$ %#(,$ (#,+$ %#!!$ *#'*$ %#%$ ,,#*$ !'#%$ '#,!$

<>& '#(%$ )#%!$ )#!$ (#!($ )#)'$ (#+&$ (#&($ *#'*$ %#"+$ ++#($ '#!,$ )#'%$

<?& %#'($ )#**$ '#"*$ (#,+$ )#"!$ (#&($ (#)&$ *#'*$ (#%,$ !*#%$ %#(,$ %#)%$

<@& )#!'$ )#+($ !"#*$ (#)&$ (#%,$ )#,)$ (#+&$ *#'*$ (#")$ !&#,$ (#&($ (#&($

<A& (#%,$ %#'($ '#+'$ (#+!$ )#(,$ %#+($ (#!($ *#'*$ *#&,$ !)#'$ (#')$ (#)!$

<B& !)#'$ $ %#&+$ (#")$ %#'($ %#*+$ (#")$ *#&,$ *#))$ !!#,$ (#)&$ %#*+$

)C& )#%&$ $ &#(*$ (#!($ !!$ %#%'$ *#&,$ *#))$ *#))$ !($ %#*+$ %#%$

);& %#(,$ $ )#'%$ $ &#"&$ $ *#&,$ *#'*$ $ !"#%$ $ $Table 38 Discharges 2001

69

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& ,#)'$ !"#&$ +#)+$ *#)($ !#%)$ !#"+$ "#)%$ "#'($ "#*,$ "#+!$ "#%+$ )#,)$

<& *#+)$ !"#($ +#&+$ '#*%$ !#&$ !#"+$ "#),$ !#!*$ "#*,$ "#+$ "#%($ &#"!$

)& +#&+$ !(#&$ ,#&*$ ,&#*$ !#'%$ !#"%$ "#),$ "#&'$ "#*,$ "#+$ "#%,$ '#*,$

=& +#+($ !(#+$ !,#,$ (#%&$ !#'%$ !#"+$ "#)!$ "#'!$ "#*,$ "#+$ "#%)$ '#%($

>& +#)+$ &#!$ ,#'&$ *#&&$ !#',$ !#()$ "#%)$ "#),$ "#*!$ "#+$ "#%($ )#,)$

?& *#,&$ !!#*$ &#&$ (#(!$ !#)($ !#,($ "#%)$ "#%,$ "#*!$ "#+!$ "#%+$ !"#($

@& &#*&$ !,$ ,#+'$ +#!)$ ,#'&$ !#"&$ !#+)$ "#()$ "#*!$ "#+!$ "#(($ &#%,$

A& (#!%$ !(#,$ *#**$ ,#'&$ ,#%,$ "#&'$ !#!)$ "#(,$ "#*!$ "#+!$ "#(,$ ,"#!$

B& )#(,$ !"$ ,#++$ *#,&$ *#")$ !#"&$ !#"&$ "#%)$ "#*$ "#+,$ "#&*$ &#)($

;C& !*#'$ '#*%$ ,#*)$ +#,&$ *#!*$ !#!)$ !#"!$ "#('$ "#*$ "#+!$ !#"&$ !"$

;;& +#,+$ ,"#'$ ,#*+$ (#*,$ ,#'&$ !#&*$ !#+!$ "#(,$ "#*$ "#+,$ "#&*$ &#+'$

;<& %#+%$ ,!$ (#)'$ *#**$ ,#+'$ !#()$ !#*$ "#(!$ "#*$ "#+,$ "#'&$ !+#*$

;)& &#*&$ !!#!$ +#%$ %#"%$ !#%)$ !#*$ !#,,$ "#*%$ "#+'$ "#+,$ !#"!$ ,+#!$

;=& (#')$ !"#($ *#&&$ (#%$ ,#*+$ !#!!$ !#!!$ "#*($ "#+%$ "#++$ "#')$ ,*#+$

;>& +#'$ !&#'$ (#')$ +#(*$ +#,&$ "#&*$ !#*+$ "#(!$ "#+%$ "#+,$ "#),$ ,,#,$

;?& *#,&$ +!$ ,#*+$ )#!&$ (#,($ "#&*$ !#+!$ "#(!$ "#+%$ "#+!$ "#%$ ,"#'$

;@& *#+)$ !+#($ ,#%)$ ,#++$ %#!%$ "#&!$ !#!!$ "#*&$ "#+%$ "#+,$ "#%($ $

;A& )#(,$ +(#&$ (#%&$ *#&&$ )#(,$ "#'&$ !#"!$ "#*'$ "#+%$ "#+,$ "#)*$ $

;B& !*#,$ ))#)$ *#)($ ,#+'$ !#)($ !#"!$ "#'&$ "#*'$ "#+($ "#+,$ !#!!$ $

<C& !&#'$ ,(#($ +#)+$ ,#%)$ )#*!$ "#&'$ "#'+$ "#*%$ "#+*$ "#++$ !#()$ $

<;& !+$ !'#)$ +#,&$ *#,&$ !#)'$ !#!*$ "#)*$ "#*%$ "#+*$ "#+,$ !#,'$ $

<<& !"$ )#(,$ *#'+$ +#,&$ !#%)$ !#,,$ "#%&$ "#*($ "#+*$ "#+,$ "#),$

<)& !(#)$ !*#,$ %#)%$ +#!)$ !#+)$ !#"!$ "#%,$ "#*($ "#++$ "#++$ "#&*$

<=& !!#)$ !,#'$ '#,,$ +#%)$ !#!&$ "#&*$ "#%$ "#*($ "#++$ "#++$ "#&'$

<>& !!#($ +!#*$ !,#+$ +#,&$ !#"&$ "#&*$ "#'($ "#*($ "#++$ "#+*$ "#'+$

<?& '#'*$ !!#*$ !!#*$ *#%)$ !#!)$ "#')$ !#"%$ "#*($ "#++$ !#!!$ "#%,$

<@& +,#*$ %#!%$ +#'$ +#*)$ !#!*$ "#'+$ !#"%$ "#**$ "#++$ !#"!$ "#'!$

<A& !'$ +#(*$ ,#++$ *#+)$ !#!!$ "#)%$ "#&'$ "#**$ "#+!$ "#'&$ "#%&$

<B& !*$ $ !*#,$ *$ !#!!$ "#)&$ "#'+$ "#**$ "#+!$ "#)&$ !#)!$

)C& !'#,$ $ !+#&$ !#',$ !#"&$ "#'!$ "#)!$ "#**$ "#+!$ "#)!$ !#(+$

);& '#(&$ $ '#(&$ $ !#"&$ $ "#)'$ "#*,$ $ "#%($ $

Table 39 Discharges 2002

70

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& ,#))$ ,#"*$ ,#")$ ,!#(($ !#&'$ ,#"!$ !#(($ !#,!$ !#&%$ "#%+$ +#%!$ +#"%$

<& !(#*%$ ,#,$ +#*,$ ,#'($ )#!+$ !#)($ !#&%$ !#"%$ !#,'$ "#(%$ +#,%$ +#"+$

)& *#&)$ *#)!$ ,#)($ !#*,$ *#&&$ !#(&$ ,#!!$ "#&+$ !#,'$ "#(+$ %#!$ ,#!!$

=& '#',$ *#%)$ !#&%$ !#")$ ,#!+$ !#*)$ ,#",$ !#!)$ "#&%$ "#(!$ +#*,$ )#)$

>& ,#,($ &#&+$ !#%*$ !#'($ !#%*$ !#,($ !#&'$ !#&*$ "#',$ "#*&$ +#!'$ !*#+)$

?& %#*'$ !,#!&$ &#,($ !#&)$ !#,+$ !#!($ !#)($ !#&+$ "#'*$ !#+($ +#+($ !"#*+$

@& ,#,($ ,)#,'$ ,#+)$ ,#(*$ !#&$ !#"&$ !#(($ !#%)$ ,#"%$ ,#+%$ ,#"+$ *#"!$

A& !#*,$ !!#(($ ,#+*$ !#))$ %#!+$ !#%'$ !#%,$ !#(!$ !#&'$ ,#"'$ !#'*$ ,#)%$

B& +#!)$ +#&!$ ,#"+$ !#,*$ ,#,'$ !#&%$ ,#"&$ !#,&$ !#%)$ !#'&$ +#!'$ %#))$

;C& (#,'$ ,#"*$ '#&,$ !#&*$ )#)&$ !#%$ !#'($ !#"&$ !#*)$ !#'*$ !+#&$ *#"!$

;;& %#''$ !#(,$ (#)%$ ,#",$ ,#+&$ !#*+$ *$ "#&$ !#*)$ ,#"!$ +#)*$ &#'&$

;<& +#&*$ ,#%,$ ,#!%$ %#*'$ ,#!%$ ,#*%$ ,#!($ !#'&$ !#,&$ !#)!$ ,#'*$ ,#+&$

;)& ,#"&$ !#&%$ +#&*$ %#($ %#!*$ ,#*%$ ,#!($ ,#"%$ !#"&$ !#(!$ +#*$ ,#&%$

;=& ,#+&$ +#+%$ +#+&$ !!#!)$ ,#(!$ ,#(%$ !#'&$ !#%*$ "#&+$ !#+,$ &#''$ ,#"%$

;>& ,#!,$ ,#!%$ ,#!,$ +#++$ !#'%$ ,#*%$ !#%+$ !#**$ "#',$ !#!&$ )#&+$ '#+!$

;?& )#)$ +#+!$ *#(%$ ,#",$ !#,)$ !#))$ !#!!$ !#,($ "#)&$ !#+$ ,#))$ *#',$

;@& !(#+'$ (#+)$ *#'!$ *#'($ ,#%%$ !#*'$ "#&%$ !#!($ "#)%$ '#*'$ +#()$ ,#!)$

;A& +#%'$ ,#,($ ,#!+$ ,#!*$ ,#!*$ *#%!$ "#')$ !#),$ !#!$ )#,!$ )#+'$ +#"'$

;B& '#%%$ !#%'$ %#)*$ %#)*$ ,#",$ ,#!)$ "#',$ !#(&$ !#),$ ,#,)$ )#!%$ !'#**$

<C& !!#!($ ,#%,$ !,#'+$ !#')$ !#&+$ !#),$ "#)*$ !#"*$ !#(($ !#)($ '#',$ %$

<;& ,'#)$ +#!$ ,#(!$ !#&%$ !#''$ !#(!$ "#)+$ "#&+$ !#,&$ !#(&$ (#!,$ %#!&$

<<& )#*&$ *#%'$ %#!*$ !#&+$ !#%)$ !#,+$ "#)!$ "#',$ !#,'$ !#*$ !(#*$ +#*,$

<)& %#!($ ,#"'$ !#'&$ !#)!$ !#(($ ,#%!$ "#)!$ "#)&$ !#"%$ !#,($ %#%$ &#,!$

<=& !,#*!$ +#")$ ,#('$ *#(($ !#*)$ ,#*%$ "#)!$ "#)&$ "#&$ ,#')$ !+#'&$ ,#*!$

<>& +#%,$ ,#!!$ !#))$ ,#!+$ !#,($ !#&($ "#%*$ "#)&$ "#)!$ %#&'$ !,#+($ *#"!$

<?& +#&,$ (#)&$ ,#"($ ,#,$ !#!($ ,#"%$ "#%,$ "#)&$ "#%*$ )#&$ !!#!)$ !#&)$

<@& !#)&$ ,#&($ !#&'$ ,#!%$ !#"&$ !#%$ "#%$ "#'!$ "#(%$ (#(($ !,#)*$ *#)$

<A& ,#,+$ %#*+$ !#&+$ ,#(*$ "#''$ !#('$ "#(%$ "#'!$ "#(+$ ,#)'$ !!#(($ ,#,,$

<B& +#)%$ $ *#(%$ '#,,$ "#',$ !#')$ "#)$ ,#+*$ !#!&$ ,#&+$ ,"#,&$ ,#%&$

)C& ,#,,$ $ ,#!+$ +#(!$ "#)*$ !#%$ !#"!$ ,#!,$ !#&&$ +#!!$ !'#',$ *#&($

);& ,#(&$ $ ,"#%!$ $ "#)+$ $ ,#%($ !#)($ $ +#+($ $ ,#!*$Table 40 Discharges 2005

71

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& ,#,)$ &#!,$ +#"($ !#&!$ !#''$ "#)'$ !#"+$ "#%,$ "#)!$ "#+!$ "#+$ !#+*$

<& ,#*($ +#**$ %#"!$ !#(($ !#),$ "#)'$ !#!+$ "#%!$ "#),$ "#+!$ "#+($ !#,'$

)& %#(&$ )#!+$ ,#)%$ !#+'$ !#&+$ "#)($ !#($ "#%!$ "#%&$ "#+!$ "#,)$ %#*%$

=& ,#)+$ )#))$ %#''$ ,#**$ %#('$ "#)$ !#(($ "#%!$ "#%&$ "#,&$ "#,+$ )#%$

>& ,#(!$ *#,$ +#!!$ +#+$ *#(($ "#%*$ !#*!$ "#(&$ "#%($ "#,&$ "#+%$ !#'%$

?& &#!)$ !,#,%$ %#"&$ +#&)$ ,#!)$ !$ !#,+$ "#(&$ "#%($ "#,)$ "#+,$ )#%'$

@& ,#)'$ %#%$ ,#+)$ +#&+$ !#%!$ !#%,$ !#!+$ "#(&$ "#%($ "#,)$ "#*!$ '#,+$

A& +#*+$ (#&,$ !#%!$ %#**$ !#,&$ !#+&$ !#%($ "#(&$ "#%($ "#,)$ "#('$ !"#+&$

B& (#,'$ +#*+$ ,#'+$ )#!'$ ,#"'$ !#!'$ !#(,$ "#()$ "#%,$ "#,)$ "#%*$ +"#!*$

;C& '#*+$ %#"($ ,#"!$ ,#(,$ %#&%$ !#"'$ !#*$ "#()$ "#%,$ "#,($ "#(!$ (#"&$

;;& &#'*$ %#'%$ ,#*&$ !#'+$ %#+($ "#'&$ !#,&$ "#()$ "#%,$ "#,($ "#)!$ !#%'$

;<& ,%#(($ ,#*!$ !#&($ ,#"+$ ,#,'$ "#'!$ !#!%$ "#()$ "#%$ "#,*$ "#(&$ !#,+$

;)& ,%#"*$ !#&!$ ,#%+$ '#')$ !#'($ "#)($ !#"+$ "#(($ "#%$ "#,*$ "#(,$ !"#*)$

;=& &#'%$ *#%($ ,#"&$ (#%*$ ,#++$ "#)$ !$ "#(($ "#%$ "#,,$ "#+'$ ,,#&,$

;>& ,(#)$ ,#*,$ !#%$ *#''$ +#+'$ "#'$ "#&+$ "#(($ "#%$ "#,!$ "#+%$ +"#'($

;?& &#*%$ !#)$ !#')$ +#"*$ !"#!$ "#)'$ "#&$ "#(($ "#('$ "#,,$ !#(!$ !%#()$

;@& !!#!,$ *#*,$ !#%)$ +#,$ ,#))$ "#),$ !#(%$ "#(+$ "#('$ "#*%$ !#**$ ,,#+'$

;A& !!#,!$ ,#'($ ,#*,$ ,#*!$ !#&$ "#%($ "#'($ "#(+$ "#('$ "#*$ !#,$ ,,#"&$

;B& &#!%$ +#(*$ '#&+$ (#"*$ !#)!$ "#%+$ "#',$ "#(+$ "#('$ "#($ !#")$ +*#'&$

<C& !!#),$ ,#+%$ !#**$ '#()$ !#(!$ "#(&$ "#)&$ "#(+$ "#('$ "#*$ "#''$ ,'#+)$

<;& *#(!$ ,#*!$ !#%)$ (#+)$ !#%&$ "#(+$ "#)&$ "#($ "#(%$ "#+,$ "#))$ "#"%$

<<& )#,'$ !'#%,$ !#%%$ ,#*'$ !#!!$ "#($ "#)%$ "#($ "#(*$ "#,)$ "#%+$ !(#%)$

<)& ,+#*'$ %#)%$ !#&!$ (#,$ "#&+$ "#*!$ "#)%$ "#($ "#($ "#,,$ "#)+$ ,(#(($

<=& +"#'*$ +#,$ !#,*$ '#+)$ "#'*$ "#+%$ "#)%$ "#($ "#+&$ "#,,$ !#"($ !(#"($

<>& !&#'+$ ,#+&$ ,#,&$ '#%$ "#'*$ "#++$ "#)+$ "#($ "#+&$ "#+'$ "#&!$ *#&)$

<?& '#)%$ (#+*$ ,#&$ )#'$ !#%,$ "#+($ "#)+$ "#($ "#+)$ "#('$ "#))$ ,)#+,$

<@& ,,#(&$ (#%,$ (#&'$ +#!($ !#*+$ "#++$ "#)!$ "#($ "#+%$ "#%&$ "#%($ '#,*$

<A& !'#+%$ (#*)$ ,#*&$ !#'&$ !#!&$ "#,($ "#%%$ "#($ "#+*$ "#(!$ "#(*$ +#($

<B& !"#&&$ $ ,#"%$ !#%*$ !#"($ "#,,$ "#%*$ "#($ "#+,$ "#+!$ "#(%$ &#'+$

)C& !,#(*$ $ !#&%$ !#(&$ "#')$ "#,*$ "#%,$ "#($ "#+,$ "#,*$ ,#%'$ !+#**$

);& !(#%($ $ !#'+$ $ "#'*$ $ "#%,$ "#(,$ $ "#,!$ $ !,#%%$Table 41 Discharges 2006

72

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& &#!'$ *#+$ !#&+$ ,$ ,#+($ ,#"%$ ,$ !#(!$ "#'!$ "#',$ "#(*$ !#%($

<& *#(%$ *#*'$ ,#"%$ !#)($ ,#&!$ !#)($ !#'*$ !#+&$ "#)&$ "#)%$ "#*!$ !#,($

)& ,#"'$ &#*'$ )#+,$ !#(&$ +#!!$ !#(&$ !#%+$ !#,'$ "#)*$ "#)!$ "#+*$ !#"&$

=& !#(,$ ,*#&&$ (#))$ !#*)$ *#!!$ !#*)$ !#(!$ !#!%$ "#)+$ "#%*$ "#*$ ,#($

>& !#*)$ !"#&'$ ,#,!$ !#,($ ,#()$ !#,($ !#+&$ !#"%$ "#)+$ "#('$ "#''$ ,#!+$

?& !#('$ !!#%&$ !#()$ !#!($ !#&!$ !#!($ ,#!+$ "#&+$ "#)!$ "#)'$ ,#%&$ ,#(&$

@& !#')$ !*#(,$ ,$ !#"&$ %#+!$ !#"&$ !#&'$ "#')$ "#)!$ "#)!$ %#%$ !#&%$

A& !#+$ )#!%$ "#)%$ !#!,$ ,#')$ !#%'$ ,#!($ "#',$ "#)!$ "#)+$ (#%%$ !#'*$

B& ,#&+$ %#++$ (#)%$ ,#")$ ,#()$ !#&%$ +#&*$ "#)%$ "#%%$ "#")$ ,#,!$ ,#!$

;C& ,#!($ !"#&+$ ,#)+$ !#(+$ +#+&$ !#%$ (#(($ "#'&$ "#%%$ "#&+$ !#%'$ +#!*$

;;& !#%*$ !*#"'$ %#!%$ !#,%$ ,#%&$ !#*+$ ,#!%$ "#',$ "#%*$ "#',$ !#,&$ ,#!!$

;<& ,#*,$ ,,#'&$ &#))$ +#&)$ ,#!'$ ,#"*$ !#)!$ "#)&$ "#%*$ "#)%$ *#'&$ !#%*$

;)& )#)!$ !%#!*$ !%#&%$ ,#!($ +#%&$ !#'($ !#(!$ "#)*$ "#%*$ "#%%$ (#)($ !#%,$

;=& ,*#),$ !%#!+$ !!#!+$ !#()$ %#+'$ !#(%$ !#+,$ "#)!$ "#%,$ "#%,$ '#*%$ ,#&*$

;>& !)#*+$ !'#&)$ !"#')$ !#,%$ ,#),$ !#*+$ !#($ "#)!$ "#%,$ "#%$ *#+&$ '#(($

;?& )#(($ !+#'($ +#&)$ *#%$ !#(&$ !#,($ ,$ "#%*$ "#%$ "#(%$ ,#!!$ (#&$

;@& (#%'$ !"#%,$ ,#"&$ ,#,,$ !#,%$ !#!,$ ,#!($ "#%,$ "#%$ "#*&$ !#%$ *#,,$

;A& '#,*$ !+#!$ !#%$ !#'($ !#&&$ ,#"+$ %#,+$ "#%$ "#('$ "#*!$ !#,%$ +#,'$

;B& !(#+&$ !!#%'$ !#'+$ !#*!$ !#'&$ !#&+$ +#!&$ "#('$ "#(%$ "#+%$ "#&%$ ,#,($

<C& +,#%$ )#)$ ,#"!$ ,#!+$ !#(,$ !#%)$ ,#"%$ "#(%$ "#(+$ "#+*$ !#"($ !#&'$

<;& !'#"($ *#&,$ !#%$ +#',$ !#,%$ ,#+)$ !#&'$ "#(+$ "#(+$ ,#*)$ ,#%$ ,#%&$

<<& '#),$ !#'%$ !#*+$ )#))$ !#'!$ ,#!,$ !#%*$ "#(($ !$ !#&!$ (#!'$ +#+&$

<)& (#*!$ ,#"($ !#,($ )#%($ )#&&$ !#&*$ !#(!$ "#&!$ !#)!$ !#%)$ +#+'$ ,#)*$

<=& %#,)$ +#(($ !#"&$ %#!&$ +#"*$ !#%)$ !#('$ ,#**$ !#,)$ !#(!$ ,#!,$ *#'$

<>& ,"#)'$ )#%)$ !#",$ (#"!$ ,#!*$ !#(!$ ,#+)$ ,#!)$ !#"%$ ,#"*$ !#%'$ ,#!'$

<?& !&#($ (#+!$ "#&+$ ,#!*$ !#'&$ !#+,$ ,#!)$ !#&'$ "#&$ ,#!!$ !#%,$ ,#)*$

<@& ,"#&%$ +#*&$ "#',$ !#)!$ !#%+$ !#!%$ ,#"+$ !#(%$ "#))$ (#'$ '#%$ )#%+$

<A& !'#+*$ ,#"'$ "#)&$ +#"!$ !#,%$ !#'($ !#'*$ !#,+$ "#%,$ ,#'$ !(#)!$ (#"'$

<B& ,,#($ $ "#('$ (#!,$ !#&*$ !#%)$ ,#"!$ !#"+$ "#(,$ ,#"($ !,#(($ +#'$

)C& !&#+&$ $ "#($ )#&,$ !#&+$ !#(!$ !#'&$ "#''$ "#+,$ !#%'$ '#,!$ (#,,$

);& !)#%($ $ "#*)$ $ !#&)$ $ !#%+$ "#)*$ $ ,#"&$ $ +#%$Table 42 Discharges 2007

73

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& ,#"($ ,#"!$ ,#(($ ,#('$ ,#!)$ !#&+$ !#&!$ !#'%$ !#'%$ !#&+$ ,#%&$ ,#!'$

<& !#%)$ !#),$ ,#!%$ ,$ ,#(+$ !#&$ !#&,$ !#'($ !#')$ !#',$ +#*($ !#'&$

)& !#(*$ !#&%$ !#'&$ )#(+$ ,#"($ ,#"+$ !#''$ !#'*$ !#)$ !#('$ (#!+$ !#'!$

=& )#",$ )#!+$ !#%+$ +#)'$ *#'+$ !#&%$ !#'($ !#'*$ !#%$ !#*,$ ,#!&$ !#%)$

>& +#+*$ +#+&$ !#+&$ ,#!%$ ,#,!$ !#'*$ !#)!$ !#)+$ !#(($ !#,)$ ,#!($ !#%!$

?& ,#,$ ,#"!$ )#&*$ &#!%$ ,#"!$ !#%+$ !#%)$ !#(&$ !#(!$ !#!($ ,#+!$ !#(&$

@& !#&)$ !#()$ *#''$ )#++$ !#%($ !#(&$ !#%*$ !#%%$ !#*)$ ,#(*$ +#(%$ !#%%$

A& !#)$ !#+,$ +#(+$ ,#,$ !#($ !#(,$ !#(&$ !#%,$ !#**$ ,#!+$ '#%($ ,#"*$

B& !#($ ,#),$ ,#!)$ ,#)($ !#*+$ !#($ !#('$ !#%,$ !#*$ !#&,$ &#&($ !#&,$

;C& *#"&$ '#%*$ !#%,$ ,#!'$ *#**$ !#*%$ !#(($ !#%$ !#,*$ &#+$ !,#',$ !#),$

;;& ,#,+$ *#+%$ '#+&$ &#)&$ ,#,$ !#+&$ !#(!$ !#()$ ,#%,$ (#!($ %#"!$ !#('$

;<& !#'*$ ,#!!$ ,#++$ %#!,$ !#&'$ !#,)$ !#*'$ !#(($ +#&($ ,#,%$ ,#'*$ !#(,$

;)& !#%$ !#&$ !#%$ *#"'$ !#)*$ !#!&$ !#*%$ !#*)$ ,#")$ ,#"*$ +#,,$ '#*&$

;=& !#*'$ ,#%,$ +#%%$ ,#!&$ !#%,$ !#!'$ !#*,$ !#*,$ !#&*$ !#'+$ +#%)$ ,#++$

;>& ,#!+$ (#',$ ,#)*$ !#'+$ !#(($ !#!($ !#+%$ !#,*$ !#%*$ !#(%$ ,#,,$ !#&$

;?& ,#"!$ &#"!$ ,#!*$ !#*'$ !#($ !#!,$ !#,'$ !#,!$ !#*,$ !#+$ (#&)$ !#%)$

;@& !#),$ ,#+%$ !#),$ +#")$ !#+'$ !#"&$ !#,($ !#!'$ !#,)$ !#!%$ &#+,$ !#(*$

;A& !#(!$ !#&&$ ,#%&$ !(#%)$ !#,)$ !#"&$ !#,,$ !#!%$ !#!&$ ,#"*$ !!#))$ !#*,$

;B& !#,'$ !#&%$ !#'&$ ,#%&$ !#,!$ !#"&$ !#!'$ !#!*$ "#&$ (#!%$ +#()$ !#,%$

<C& !#,!$ !#)*$ !#(&$ '#**$ !#!)$ !#"%$ !#!'$ !#"&$ "#'%$ ,#,+$ '#*%$ !#,*$

<;& !#"&$ !#(+$ ,#%*$ !!#+$ !#!($ !#"!$ !#!,$ !#"%$ "#',$ !#&,$ (#!&$ !#!&$

<<& "#&,$ !#,'$ ,#!,$ ,)#&,$ !#!!$ "#&+$ !#"&$ !#"+$ "#)&$ !#%!$ *#!)$ !#!%$

<)& "#'*$ !#"'$ !*#%%$ &#%($ !#"%$ "#&,$ !#"($ "#&+$ "#)%$ ,#!'$ ,#!,$ !#"*$

<=& "#)%$ "#')$ ,#(($ *,#&$ !#",$ "#&$ !#",$ "#&,$ "#)+$ ,#"*$ )#!$ +#",$

<>& ,#"*$ !#!)$ (#&&$ !*#)%$ "#&,$ "#&$ !#",$ "#'&$ "#%&$ '#'($ '#'%$ ,#"&$

<?& ,#!&$ !#%&$ )#%!$ !"#"%$ "#''$ "#')$ "#&,$ "#')$ "#%!$ '#'$ +#,($ !#%+$

<@& ,#"*$ !#*+$ )#,&$ '#+!$ "#'($ "#')$ "#&$ "#'($ "#(&$ ,#*!$ ,#!&$ !#($

<A& !#%($ !#,!$ ,#+,$ !,#)($ "#'!$ "#'*$ "#')$ "#',$ "#('$ !#&*$ !"#'($ !#,&$

<B& !#*($ "$ !#()$ ,#*)$ "#)%$ "#',$ "#'*$ "#'!$ "#(%$ !#%%$ +#,($ !#,!$

)C& *#"&$ $ ,#!$ +#)+$ "#)+$ "#)&$ "#',$ "#)'$ "#(+$ +#!%$ %#('$ !#!)$

);& ,#,+$ $ ,#!*$ $ "#%%$ $ "#%%$ "#%%$ $ +#*+$ $ (#,$Table 43 Discharges 2008

74

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& *#&*$ ,#'*$ ,#%($ ,#*&$ ,#+,$ ,#%!$ ,#,,$ ,$ !#(*$ ,#,($ ,#!($ +#"%$

<& !!#+$ !#'($ (#%,$ '#(+$ %#&,$ ,#+($ ,#"+$ ,#"'$ !#(+$ ,#(!$ ,#"%$ )#*($

)& *#(*$ !#%$ ,#)*$ %#!'$ ,#)+$ '#%$ !#'%$ !#'+$ !#+&$ ,#*)$ !#'+$ +#+'$

=& !*#%%$ !#*$ ,#"*$ ,#,)$ ,#'+$ +#++$ !#))$ !#)%$ !#+!$ ,#,%$ !#(!$ +#*,$

>& +#&*$ !#,($ !#),$ ,#!($ !+#*)$ ,#"($ !#%($ !#%*$ !#,'$ ,#!!$ !#+&$ ,#+($

?& +#'+$ !#!%$ !#(!$ +#+!$ (#"'$ !#'!$ !#(($ !#(&$ !#,!$ !#''$ !#,'$ !#''$

@& !"#+%$ '#+%$ +#%($ +#%'$ %#+&$ ,#!%$ !#*!$ !#(($ !#!($ !#%,$ !#,'$ %#%'$

A& +#)$ %#!,$ ,#'$ ,#*&$ ,#)&$ !#'($ !#+,$ !#*!$ "#&)$ !#+&$ ,#,+$ ,#+$

B& ,#+&$ ,#)%$ ,#,!$ !#''$ ,#"'$ !#('$ !#,'$ !#+%$ "#'%$ ,#()$ ,#")$ *#"!$

;C& '#&'$ ,#,!$ ,#"!$ !#%!$ !#%'$ ,#",$ !#,*$ !#+!$ "#'+$ +#!+$ !#''$ ,#'+$

;;& +#('$ !#&&$ &#+'$ !#**$ !#(*$ (#'*$ !#!&$ !#,)$ "#)'$ %#),$ !#)+$ ,#,&$

;<& ,#)&$ &#++$ (#,'$ +#&,$ !#*$ ,#)!$ !#!($ !#,!$ "#)+$ ,#,&$ )#*($ ,#(*$

;)& !!#%&$ +#()$ ,#)$ +#&*$ !#,&$ ,#!)$ !#!$ !#!%$ "#%*$ !#')$ +#+%$ !(#',$

;=& *#+'$ *#,'$ ,#+'$ )#,*$ !#,'$ !#&,$ "#&'$ !#!,$ "#(&$ !#(,$ ,#!*$ +#"%$

;>& ,#'($ ,#'%$ !#&&$ ,#%($ ,#,'$ !#),$ "#&+$ !#"%$ "#()$ !#,)$ &#,'$ !#,)$

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;@& '#)*$ ,#+*$ !#(,$ !#%)$ +#+&$ !#,'$ "#'%$ "#&+$ "#))$ "#&%$ !,#%&$ *#"!$

;A& *#+,$ +#,&$ ,#,&$ !#%,$ ,#++$ !#,$ "#'+$ "#&!$ *#*($ ,#,*$ %#(,$ ,#*&$

;B& +#*,$ !(#,)$ !#'$ *#'($ ,#&$ +#'*$ "#)&$ "#')$ !#',$ ,#!*$ ,#%!$ !#''$

<C& ,#)'$ (#*,$ !#%+$ %#+($ ,#&!$ ,#)+$ "#)%$ "#'+$ ,#!,$ !#'&$ ,#!&$ +#&$

<;& +#'*$ +#"*$ ,#+&$ +#!!$ (#(%$ ,#'+$ "#)$ "#)&$ ,#"($ !#)+$ %#(!$ !#)+$

<<& +#"&$ ,#**$ ,#!,$ ,$ ,#(%$ !!#"'$ "#%$ "#)%$ !#))$ !#('$ +#!,$ !#+($

<)& ,#(%$ ,#!'$ !#)($ !#%%$ ,#!%$ (#*'$ "#(%$ "#),$ ,#%!$ !#&*$ ,#"($ )#*,$

<=& ,#!%$ +#+,$ !#(($ !#*!$ ,#"($ ,#('$ "#(*$ "#%$ ,#*%$ !#+&$ !#)&$ ,#)'$

<>& ,#")$ ,#',$ !#*,$ !#,'$ ,#!$ ,#!%$ "#($ "#(%$ ,#,)$ !#&'$ +#),$ !#%)$

<?& *#(!$ ,#,!$ +#&($ ,#!)$ !#'($ !#'%$ "#*)$ "#(*$ ,#,($ !#'$ ,#,,$ +#,$

<@& '#)$ ,$ +#($ ,$ !#%'$ !#%+$ "#**$ "#*&$ ,#")$ !#%)$ ,#*)$ !#(%$

<A& *#%!$ !#'+$ ,#(!$ ,#'&$ )#+%$ !#+'$ "#*!$ "#*%$ +#)&$ !#*($ !!#+,$ !#!($

<B& ,#'!$ $ ,#!$ ,#!,$ +#+$ !#,'$ "#+'$ "#*+$ *#&&$ !#,+$ ,#),$ !!#*&$

)C& )#)%$ $ ,#*($ !#'*$ +#+!$ ,#,,$ "#+!$ "#*$ ,#*$ !#"($ %#*!$ (#)*$

);& )#%$ $ ,#*+$ $ +#(%$ $ "#+'$ "#**$ $ "#&($ $ ,#)+$Table 44 Discharges 2009

75

!"#$%&'()*+"%,& -./& 0"#& (.1& .21& (.3& -4/& -45& .46& 7"2& 89%& /8:& +"9&

;& +#,($ !)#!$ )#,($ %#",$ ,*#!$ )#",$ )#",$ (#'!$ (#&!$ %#!+$ )#,($ +#%)$

<& ,#&)$ !!#)$ !,#!$ !'#,$ !'#&$ !+#%$ !+#%$ !"#*$ !%#%$ ,'$ !!#'$ *$

)& ,#)($ ,*#+$ !+#&$ !"#'$ !,#,$ !'#)$ !'#)$ %#!+$ !(#'$ !&#'$ (#)$ (#'$

=& *#!&$ ,"#!$ !*#($ %#!+$ &#**$ )#,($ )#,($ (#'!$ !%#!$ !(#,$ )#&%$ +#)*$

>& +#+!$ &#%$ +,#)$ (#*&$ (#*&$ '#',$ '#',$ (#%$ ,)#+$ +&#%$ !"#*$ !*#&$

?& %#,&$ %#,*$ !(#+$ *#'&$ *#!&$ %#!+$ %#!+$ (#!&$ !+$ !+#%$ %#!+$ &#'($

@& +#'$ )#",$ !(#($ +"#)$ '#&+$ '#"'$ '#"'$ *#%$ !(#+$ !+#*$ !!$ !%#*$

A& *#!&$ %#!+$ %#",$ !!#,$ (#+*$ ,+#)$ ,+#)$ *#,+$ (#)$ +&#!$ !"#($ *#&%$

B& +#!&$ !*#,$ (#,&$ %#,*$ *#"%$ !%#+$ !%#+$ *#%$ )#&%$ !%#%$ ,!#'$ *#)($

;C& )#+,$ &#"'$ !,#!$ (#'!$ ,#+'$ ,+#)$ ,+#)$ %#!+$ !+#%$ )#,($ !'#($ %#*%$

;;& (#"*$ !)#%$ (#)$ %#%'$ ,$ !&#,$ !&#,$ (#&!$ ,*#)$ (#&!$ ,'#'$ !"#!$

;<& +#"'$ ,%#&$ !&#%$ %#!+$ !#&%$ '#&($ '#&($ (#!&$ !&#*$ +%#)$ ,+#($ !"#&$

;)& ,#)($ !,#($ !&#&$ (#*&$ ,#"($ !!#($ !!#($ !*$ !+#*$ !+#&$ (#&!$ )#($

;=& ,#**$ +"#)$ ,+#($ *#&&$ !#'+$ !*#*$ !+#&$ *#(!$ ,*#)$ !,#*$ ,"#($ !(#,$

;>& (#'$ !,#,$ !*#)$ &#+*$ +#*+$ '#()$ '#()$ +#&%$ ,'#,$ ,*#&$ ,,#,$ &#+*$

;?& +#,($ '#+,$ %#!+$ +!#%$ )#(&$ '#',$ '#',$ +#%!$ !(#'$ &#+*$ ,"#)$ )#)'$

;@& ,#'$ (#)$ (#+&$ !*#,$ !(#,$ &#)+$ &#)+$ %#",$ !!#'$ *+#+$ %#",$ &#**$

;A& ,#(*$ (#*&$ (#+&$ %#,*$ !+#($ !,#'$ !,#'$ (#%$ ,+#($ !(#($ &#%$ ,"#+$

;B& +#'$ +'#%$ !*#*$ (#%$ &#,+$ %#!+$ (#'!$ (#!&$ +"#!$ ,,#)$ !+$ &#&%$

<C& ,#&)$ !%#($ !"#+$ (#"&$ %#,&$ (#&!$ (#&!$ *#(!$ !+#)$ !)#($ !(#+$ )#%&$

<;& ,#%&$ (#&!$ !+#%$ *#%$ (#%*$ (#"&$ (#"&$ *#"($ %#!+$ !&$ ,&#,$ +#!&$

<<& '#**$ (#!&$ !,#!$ *#!*$ )#*!$ *#(!$ *#(!$ *#"($ (#*&$ !,#'$ ,+#($ *#)($

<)& +#",$ %#,*$ %#",$ +#%&$ *#)($ %#*($ %#*($ (#*&$ +*#+$ !!#'$ +(#)$ %#(*$

<=& !($ !'$ (#,&$ +#**$ +#!*$ !!#,$ !!#,$ *#&&$ !!#)$ ,!#*$ !%#+$ %#(*$

<>& %#+)$ !,#'$ ,!#'$ +#,)$ !#($ !+#&$ !+#&$ *#)$ (#'!$ !(#,$ +($ ,#&!$

<?& +#,($ (#&!$ +'#!$ (#&!$ +#",$ !)#+$ !)#+$ *#+,$ +(#)$ '#)$ !%#($ *#,%$

<@& ,#'$ (#!&$ !!$ (#+&$ ,#+*$ !,#*$ !,#*$ +#')$ !'#,$ !+#*$ !%#!$ )#)'$

<A& ,#**$ !*$ '#',$ *#&&$ +#%!$ *"#'$ *!$ +#(,$ !,#'$ !!#'$ )#!+$ +#,($

<B& !!#*$ $ !"#($ *#)&$ )#"%$ +%#)$ +%#)$ !(#,$ !%#'$ !(#%$ ,&#)$ '#!($

)C& +#!&$ $ &#)+$ *#*!$ !(#*$ *&#%$ *&#%$ '#',$ ,(#($ !*#)$ ,,#)$ *#*$

);& +#"'$ $ %#!+$ $ !(#%$ $ *%#&$ %#",$ $ +($ $ *#'&$Table 45 Discharges 2010

Appendix Q Flow Type

This appendix treats the type of flow (by average discharge of 5.54 m3/s) and the estimation

of the Chézy coefficient, which is used for making assumptions about the river transport in

the past 10 years. For instance, subcritical flow secures a thrust curve with an exact end of

water level rising, whereas supercritical flow makes a thrust impossible. The Chézy

coefficient is determined by the wet profile height (Appendix O) and the properties complete

profile (Appendix N). Input values are the next parameters: the average discharge (Qgem), the

total surface of the profile (Atot), the average width and the river gradient (i).

Qgem = 5.54 m3/s

b =10 m

i = 0.004

The water depth (h) and specific energy (H) are

presented to determine several parameters for

the use in the sediment transport. The flow will be

given in subcritical or supercritical. The graph in

figure 36 is used with the critical values of the

water level (hc) These calculations provide values

for the formulas of Meyer-Peter & Muller and

Engelund & Hansen [Nortier & de Koning, 1996].

hc =Q

2

gb2

3 =5.54

2

9.81!102

3 = 0.32 m

The Chézy coefficient is needed and can be

derived from using the d90, which is coming from

the sediment classification in Chapter 7. The C

value can be read from the graph (figure 37) with

the wall roughness (k). To estimate the Chézy

coefficient, the wet river profile height (hw).

k = d90= 4.00 mm

hw

k=0.95

0.004= 238

C = 25hw

k

!

"#

$

%&

1

6

= 25 238( )1

6 = 62 m

1

2 /s

With the first estimation of the Chézy

coefficient, new data can be derived

from the average discharge. It is about

the equilibrium water depth (he), which

will be compared with the critical depth.

Therefore, the coefficient of Chézy

need to be determined in the under

Figure 36 Diagram in Water Depth and Specific Energy by Nortier & de Koning [1996]

Figure 37 Chézy coefficient from h/k factor by Nortier & de Koning [1996]

77

mentioned iterative procedure. The iteration from equilibrium depth, to the h/k factor, to the C

is shown in table 46. The first equilibrium depths are transcribed in the formulas.

he =Qgem

2

b2C

2i

3 =5.54

2

102!62

2!0.004

=3 0.27 m

h

k=0.27

0.004= 68

C = 25h

k

!

"#$

%&

1

6

= 25 68( )1

6 = 51 m1

2 /s

he =Qgem

2

b2!C

2! i

3 =5.54

2

102!51

2!0.004

=3 0.31 m

Accordingly, the Chézy coefficient is 52 after iteration (it.) 2 and the equilibrium depth is set

to be 0.31 m. As a result, the critical depth of 0.32 m exceeds the equilibrium depth of 0.31 m.

This means that the river is in the phase of supercritical flow against the transition phase.

A confirmation is that a stone was thrown into the river to see the direction of the

disturbance. This impact was completely moving downstream, indicating supercritical flow.

In short, the two parameters point to supercritical flow and the transition phase. There

is uncertainty in all the used parameters (b, i, hc, k, he) except the discharge. With this

uncertainty, the close values and the stone test can be said that the water is supercritical in

the narrowest profile.

This entire means that upstream, where the river is wider and the flow velocity are

lower, the flow is subcritical with the security of a thrust curve, when the check dam is built.

!"#$ %&$ %'($ )$

*$ $+$ $+$ ,-$

.$ *#-/$ ,0$ 1*$

-$ *#2.$ !"# $%#

&# '(&)# !!# $%#

*# '(&)# !!# $%#

$# '(&)# !!# $%#

+# '(&)# !!# $%#

!# '(&)# !!# $%#

Table 46 Iteration for Chézy coefficient

78

Appendix R Sediment Motion

This appendix speak about the sediment transport approached by Meyer-Peter & Müller and

Engelund & Hansen. Every grain diameter needs a different force of the flow to move it. The

d50 is used to make assumptions about the total sediment transport of all the sizes treated.

Input values for the bed movement are summed up here.

Qgem = 5.54 m3/s

C = 52 m1

2 /s

b =10 m

h = 0.31 m

i = 0.004

Chézy is used to determine the average flow velocity by friction losses due to the bed

roughness. This leads to the minimum speed for erosion (ver) given in the next formula. The

variable 'a' is an empirical bed roughness constant.

ver= a !C d

50= 0.28 !52 ! 0.00053 = 0.34 m/s

The hydraulic radius (R) is required to determine the flow velocity for the treated section of

the river.

R =hb

2h+ b=

0.31!10

2 !0.31+10= 0.29 m

v = 0.66C Ri = 0.66 !52 ! 0.29 !0.004 =1.17 m/s

The minimum velocity is exceeded by the cross-section average velocity (v), which means

sediment transport at this section of the river.

This assumption is followed by Meyer-Peter & Müller. This formula calculates the bed

load transport (Qmpm) with the next equation with an uncertainty of ± 50%.

Qmpm =16b !v

C

"

#$

%

&'

2

( 0.08d50

"

#

$$

%

&

''

3

2

=16 !10 !1.17

52

"

#$

%

&'

2

( 0.08 !0.00053

"

#$$

%

&''

3

2

=1.61!10(3

m3/s

This number excludes the pores of 0.46 from Appendix I. The total quantity of bed load

transported is given in the next formula.

Qmpm =Qmpm ! (1+!p ) = 3.0 !10"2! (1+ 0.46) = 2.35 !10

"3 m

3/s

This means 74.2 thousand m3/year and 742 thousand m3 in 10 years for the bed load to

arrive in the reservoir.

Engelund & Hansen combined the bed load and suspended load, excluding wash load,

d90= 4 mm

d50= 0.53 mm

79

in one formula [Bezuyen, Stive, Vaes, Vrijling & Zitman, 2007]. This number will be used for

the design of the check dam and its expiration time. seh is the total bed and suspended load

supply per meter of width. Multiplied by the width is the volume per unit of time.

seh = 0.03!g

C2

"

#$

%

&'

3

2

!v

5

g2 !d

50

= 0.03!9.81

522

"

#$

%

&'

3

2

!1.17

5

9.812 !0.00053

= 2.8 !10(4

m3/s/m

Qeh= s

eh!b = 2.8 !10

"2!10 = 2.8 !10

"3 m

3/s

This number is the same with sedimentation of 88.9 thousand m3/year and 889 thousand m3

in 10 years in the reservoir. Similarly, suspended load is more than twice the amount of the

bed load.

In the formula of Meyer-Peter & Müller there is already an uncertainty of 50%. The

scarce data provided, the low quantity of measurements, the diversity of the river

characteristics and the fluctuations of the discharges throughout the year can cause more

uncertainty in the obtained numbers. Furthermore, wash load is not taken into account, which

can be more than double the total amount of sedimentation.

80

Appendix S Expiration Time

The sedimentation starts at 160 m (ltot) upstream of the check dam. This layer of sand will be

approximately horizontal. The amount can be calculated by a triangle (section 9.2). The

lengths and widths in front of the check dam (lch, bch), the reservoir (lla, bla) and the remainder

(lrm, brm) come from figure 38. Moreover, the maximum height of the soil against the dam

(hmax) will be 1.5 m. The next formula will determine the maximum volume for the sediment

beginning at the check dam.

Vsed =1

2lbgemhmax =

1

2Atothmax

There will be a small reservoir after the built

construction of the dam, which is stimulating

the sedimentation, because the large river

profile will result in extra reduction in flow

velocities as result of decreasing slopes. The

reservoir area (Ala) can be approached by the

rectangle of 30 m in width and 80 m in length.

The residual sections of the river, which

concern the channel (Ach), are 20 m in width.

The total surface (Atot) can be determined for

the sedimentation layer. This is

lch= 20 m

lla= 80 m

lrm= l

tot! (l

ch+ l

la) =160! (80+ 20) = 60 m

Atot= l

chbch+ l

labla+ l

rmbrm

= 20 !20+80 !30+ 60 !20 = 4000 m2

Vsed= 1

2Atoth

max= 1

2! 4000 !1.5= 3000 m

3

The volume of sand catched by the designed

check dam thus will be 3000 m3.

Figure 38 Cilalawi River Widths

81

Appendix T Apron Length

The length and presence of the apron depends on the highest water level differences

between the downstream and upstream. For this calculation the maximum discharge of 77.7

m3/s (Qmax) is applied, the Chézy coefficient of 50 m1/2/s (C), the width of 15 m (b), maximum

height above the dam 2.1 m (a) and the bed slope of 0.004 (i).

The first formulas calculate the equilibrium height downstream (he,max) and lastly the

specific energy on top of the water depth.

he,max=

Qmax

2

b2C

2i

3 =77.7

2

102!51

2!0.004

3 =1.80 m

R =A

O=

hb

2h+ b=

15 !1.80

2 !15+1.80= 0.85 m

v =C Ri = 51 0.85 !0.004 = 2.97 m

The water level difference can be calculated for the maximum discharge. The specific energy

will be used for the comparison with the hydraulic jump diagram in figure 39.

Hmax,upstream = hcd + a = 2.10+ 2.10 = 4.20 m

Hmax,downstream = he,max

+v

2

2g=1.80+

2.972

2 !9.81= 2.25 m

!H = Hmax,upstream "Hmax,downstream = 4.20" 2.25=1.95 m

The specific discharge (qmax) stands for the curve with the number 5. This number is

combined with the specific energy of 2.10 m on the y-axe and gives the 1.4 m for the

minimum water level difference needed for a the hydraulic jump.

The conclusion is that a stilling basin is not essential, because the height difference of 1.95

m (< 1.4 m) creates the hydraulic jump. This phenomenon in nature is whimsical and can

manifest further downstream, where it will damage the bed and banks. Therefore, the apron

dimensions are determined using Vlotman [1989].

The formulas used will provide the flow velocity at the point where the flow is entering

the stilling basin (vu) and eventually the length of the stilling basin (Lsd).

vu= 2g!H = 2 "9.81"1.95 = 6.2 m/s

hu =q

max

vu=

5.2

6.42= 0.81 m

Lsb= 6.9(h

e,max! h

u) = 6.9(1.80! 0.81) = 6.83" 7 m

qmax =Qmax

b=

77.7

15= 5.2 m3 /s

m ! q is 5-line

82

Figure 39 Water Depth and Specific Energy for Hydraulic Jump by Bendegom [1971]

83

Appendix U Grain Size Velocities

In this appendix the law of Darcy is applied with the flow velocity under the stilling basin (and

dam) for the d10 grain size, which is 0.19 mm from Chapter 7 [Nortier & de Koning, 1996].

The smallest diameter is used to create the most favorable circumstances in which sediment

is easily transported.

The line used in figure 40 to hold the grain is situated between 'Transport as bed load'

and 'Deposition'. The minimal flow velocity to obtain the grain movement is compared with

the length apron. In the figure on the chosen line the number 0.014 m/s can be found for the

minimum flow velocity. The k-value is the permeability coefficient of the soil. This is combined

with the slope.

k = d2

10 !104= 0.00019

2!10

4= 3.61!10

"4

#h = #H =1.95 m

vd10=1.40 !10

"2 m/s

v = ki = k#h

l= 3.61!10

"4!1.95

7=1.00 !10

"4 m/s (< 1.40 !10

"2)

The 7 m stilling basin reduces the minimum velocity of d10. This means that the total check

dam length (dam with stilling basin) prevent sediment transport under the dam and assure

stability.

Figure 40 Hjulström Curve for Grain Velocities by Coolgeography [2011]

84

Appendix V Stability

The position of the check dam is always fixed and stable. The balance between the water

hydrostatic pressure with flow strength and the dam shear forces on the underground will

draw conclusions concerning this subject (figure 41).

When the dam is completely under and surrounded by water (!w = 10 kN/m3) the

volume weight will be different from what it was with only the concrete (!c = 25 kN/m3). The

result is a lifted dam with the difference between concrete and water that is 15 kN/m3 (!c).

The content of the dam is the length with the surface of the side view. This side view is

divided in four parts: the half circle (Ac), the rectangle and the two triangles (Af). The weight

of the dam is the volume with the volume weight (!c).

There are no data known about the soil under the riverbed. In the worst case there

will be clay, which has the shear coefficient with tan 20° [Bischoff van Heemskerk, 1964].

The weight of the dam and the soil shear coefficient must resist the water pressure.

The maximum shear force against the water is will be 543 kN.

Figure 41 Shear and Water Forces

m = !r!V =15 !99.48 =1492.15 kN

T =m ! tg" =1492.15 ! tan(20) = 543 kN

The water will give an opposite force from the hydrostatic pressure and flow strength (X)

combined in the next formula with the water level above the spillway (h1) and equilibrium

water level downstream (h2), both with the same reference level (Appendix P).

The water is unable to push the dam away, because the force working on the construction

(65.6 kN) is smaller than the concrete and soil shear force (543 kN).

A = Ac + Af

A = 12!r2

+ ((h !2r)+ tan("1) !h+ tan("2 ) !h

= 12! !1.79

2+ ((0.31!2 !1.79)+ tan(30) !0.31+ tan(45) !0.31) = 6.63 m

2

V = Al = 6.63!15= 99.48 m3

m = # r ! I =15 !99.48 =1492.15 kN

T =m ! tg$ =1492.15 ! tan(20°) = 543 kN

q =Q

max

l=

77.7

15= 5.18 m

3/ s /m

X =1000 ! 12!9.81(h1

2 " h2

2)" q2

(1

h1

"1

h2

)#

$%

&

'(

=1000 ! 12!9.81(4.20

2 "1.742)" 5.18

2(

1

4.20"

1

1.74)

#

$%

&

'(

=1000 ! (71.67" 6.03) = 65644 N = 65.6 kN

85

Appendix W Technical Drawings

Documents

Bachelor Thesis - Sedimentation Reduction and Check Dam Design in the Cilalawi River (GJVos)_send