SOPIA .S. SHILLAH - TITLE EVALUATION OF THE ON-GOING...

TITLE: EVALUATION OF THE ON-GOING CONSTRUCTION OF
NAROK TOWN STORM WATER DRAINAGE SYSTEM
BY
SOPIA .S. SHILLAH
F16/2289/2009
SUPERVISOR: MR. KIPKOROS KANDIE
This project is submitted in partial fulfillment for the award Bachelor of Science Civil and
Construction Engineering, University of Nairobi.
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ABSTRACT
Narok town has experienced flooding for over several decades. The consequences being people
and cars drowning, destruction of property and indirectly has a link to slow development; this is
because the risks of investing in the town is increased by the frequent floods during rainy
seasons; hence investors shy away or avoid investing all together. Road pavement destruction is
a concern as water ingress into the sub-grade. Health and environmental impacts after the
floods are also a major concern.
The study involves the evaluation of the existing major drainage system in Narok town i.e. from
Kobil petrol station to Narok River, estimation of runoff, hydraulic design of open channels,
culvert and comparing the with existing ones.
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ACKNOWLEDGEMENT
I hereby place on record my sincere gratitude to the following:
Eng: Kipkoros Kandie, my supervisor, who at every stage in my project buildup, played a
principle role by offering technical advice, relevant information, alterations, corrections,
additions and omissions to my work.
Mr. Lucas Wesonga, resident engineer for the project, who provided me with material support.
Employees of meteorological department, Dagoretti, who provided me with rainfall data,
analyzing the data and correction where necessary.
I also acknowledge the efforts of my parents, brothers and friends, for their support in my
education, financially and morally.
SOPIA .S. SHILLAH
APRIL 2015.
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Table of Contents
ABSTRACT .................................................................................................................................................... 2
ACKNOWLEDGEMENT .................................................................................................................................. 3
CHAPTER ONE: INTRODUCTION ................................................................................................................... 6
1.1 BACKGROUND .................................................................................................................................... 6
1.2 PROBLEM STATEMENT ....................................................................................................................... 7
1.3 GOALS AND OBJECTIVES .................................................................................................................... 7
1.4 SUMMARY OF APPROACH, TOOLS AND METHODOLOGY ................................................................... 8
CHAPTER TWO: LITRATURE REVIEW ............................................................................................................. 9
2.1 HYDROLOGICAL CYCLE ................................................................................................................... 9
2.2 URBAN HYDROLOGY ........................................................................................................................... 9
2.3 EFFECTS OF URBANISATION ON STROM RUNOFF ............................................................................ 10
2.4 URBAN STROMWATER MANAGEMENT ............................................................................................ 12
2.5 URBAN STORMWATER DRAINAGE DESIGN ...................................................................................... 13
2.5.1 INTRODUCTION ......................................................................................................................... 13
2.5.2 PLANNING ................................................................................................................................. 14
2.5.3 DESIGN CRITERIA ............................................................................................................... 14
2.5.4 BASIC DESIGN CRITERIA ............................................................................................................ 21
2.5.5 FLOOD ESTIMATION ........................................................................................................... 24
2.5.6 CHANNEL DESIGN .............................................................................................................. 26
2.5.7 DRAINAGE DESIGN FOR URBAN STREETS ........................................................................... 28
2.5.8 DESIGN OF CULVERTS ......................................................................................................... 29
CHAPTER THREE: RESEARCH AND METHODOLOGY ................................................................................... 33
3.1 RESEARCH APPROACH ..................................................................................................................... 33
3.2 METHODOLOGY ............................................................................................................................... 33
3.3TOOLS ............................................................................................................................................... 35
CHAPTER FOUR: RESULTS, ANALYSIS AND DISCUSSION ............................................................................. 36
4.1 INTRODUCTION ............................................................................................................................... 36
4.2 PHOTOGRAPHY ................................................................................................................................. 36
4.3 RAINFALL DATA ANALYSIS AND DESIGN OF DRAINAGE SYSTEMS ..................................................... 40
4.3.1 RETURN PERIOD ........................................................................................................................ 40
4.3.2 RUN-OFF CO-EFFICIENT ............................................................................................................. 41
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4.3.3 DESIGN OF THE OPEN DRAINS LFROM KOBIL PETROP STATION THROUGH THE SAMPURMPUR
VALLEY TO NAROK RIVER ................................................................................................................... 43
DISCUSSION ............................................................................................................................................... 47
CONCLUSIONS AND RECOMMENDATIONS ................................................................................................ 48
REFERENCES .............................................................................................................................................. 49
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CHAPTER ONE: INTRODUCTION
1.1 BACKGROUND.