TABLE OF CONTENTS
Title page i
Declaration ii
Certification iii
Dedication iv
Acknowledgement v
Abstract vii
Table of Contents viii
List of Tables xii
List of Figures xiii
Appendix (List of plates) xiii
CHAPTER ONE
1.0 Introduction 1
2.0 Statement of the problem 3
3.0 Aim and objectives 4
4.0 Justification 4
5.0 scope of the study 5
6.0 Description of the project area 6
7.0 Research methodology 6
CHAPTER TWO
2.0 Literature Review 8
2.1 Introduction 8
2.2 Blockage Issues 10
2.3 Types of Debris 12
2.3.1 Overview 12
2.3.2 Floating Debris 14
2.3.3 Non-Floating Debris 15
2.3.4 Urban Debris 16
2.4 Types of Structures and Drainage Systems 17
2.5 Causes of Blockage 18
2.5.1 Overview 18
2.5.2 Modes of blockage 19
2.6 Impacts of Blockage 20
2.6.1 Overview 20
2.6.2 Hydraulic Impacts 21
2.6.3 Economic Impacts 22
2.6.4 Social Impacts 22
2.6.5 Environmental Impacts 23
2.7 Effect of Blockage 23
2.7.1 Overview 23
2.7.2 Consequences of blockages on flooding 25
2.8 Control Measure 26
CHAPTER THREE
3.0 Methodology 27
3.1 Introduction 27
3.2 Research Design 27
3.2.1 Population 30
3.3 Data Collection Procedures 30
3.3.1 Data collection instructions 30
3.3.2 Primary data 31
3.3.3 Secondary data 33
3.4 Data Analysis and Presentation Techniques 33
CHAPTER FOUR
4.0 Data Presentation and Analysis of Result 35
4.1 Introduction 35
4.2 Results from Questionnaire 35
4.2.1 Results from Questionnaire Type One 36
4.2.2 Results from Questionnaire Type Two 36
4.3 Possible Causes of the Blockage 42
4.4 Results on Control of Blocked Drainage, Canal and
Study Area 44
CHAPTER FIVE
5.0 Conclusions and Recommendation 46
5.1 Conclusion 46
5.2 Recommendation 47
Reference 50
LIST OF TABLES
Table Title Page
4.1 Response rate in rate in Agbo-Oba, Oja-Tuntun and Sawmill 35
4.2 Number of years spent by the respondent rate in
Agbo-Oba, Oja-Tuntun and Sawmill 39
4.3 Possible causes of the blockage in Agbo-Oba, Oja-Tuntun
and Sawmill 42
4.4 Control of blocked drainage, canal and culvert 44
LIST OF FIGURES
Figure Title Page
4.1 Consideration for hydraulic design 36
4.2 Years spent by the respondent 40
4.3 Frequency of road usage by road users 41
4.4 The possible cause of the blockage 43
4.5 Control measure in Agbo-Oba, Oja-Tuntun and Sawmill 45
APPENDIXS (LIST OF PLATES)
Plate Title Page
1.0 Drainage blockage along Agbo-Oba road 54
2.0 Drainage blockage along Sawmill road 56
3.0 Drainage blockage along Oja-Tuntun, kuntu area 57
ABSTRACT
Drainage is an essential component of road construction. In most designs of the road, the first thing to be put in place is drainage system. The presence of blockage in drainage system tends to reduce the carriage capacity of drainage and thereby affect life span of the road. The research employed a research survey in order to obtain the information that would describe the causes of blocked drainage, canal and culvert in Ilorin-west local government road and its effect on the surrounding environment and the road users. Data collection techniques used includes questionnaires, photographs and observation. The results show that Ilorin-west local government road drainage system was not adequate to satisfactorily drain the runoffs due to the blockage caused by debris, illegal dumping of refuse, Non-channelization e.t.c. As a result, the surrounding environment was greatly affected by washing away some sections of the road and bridges, creation of gullies on land, washing away of the fertility of the land. The drainage facilities could be improved by frequent inspections, maintenance of gabions built for remedying of gullies and construction of water conservation structures e.g. water pans to hold and reduce the speed of water. Some drainage, canal and culvert system on Ilorin-west local government road should be redesign.
