CHAPTER ONE
INTRODUCTION
1.1 Background to the Study
The international conference in Rio that made a declaration and the Agenda 21 from the early 1990’s introduced the concept of long-term sustainability of our environment. One important ingredient in the new approach is that technical, economic and social aspects of the development are handled carefully. There is today, a consensus that urban water systems should be approached in an integrated way. Surface water, groundwater, water quality, quantity, and ecology should be looked upon in relation to each other. Thus, the introduction of the concept of sustainability has, in the field of urban water systems among others, led to an increased interest for source control and open drainage of storm water within the urban environment (Geldof and Stahre, 2006).
At present, about 2.6 billion people are living without proper sanitation, of which Africa is not exempted (Olukanni, 2013a). The need to provide proper drainage and sanitation facilities is essential to match up with the ever increasing population growth (Banerjee and Morella, 2011). The increase in the population of a settlement and the attendant growth of the needs of the residents in both quantity and variety, bring about intensive exploitation of the resources of the environment. Such exploitation might increase to a level that the resources would not be able to sustain the population, and in some cases the environment would collapse resulting in serious environmental problems (Asoegwu, 2009). This is further buttressed by Belete (2011) who expressed that high urban population growth rate also results in drainage system challenges because an increase in population requires a proportionate increase in infrastructure (roads and drainage systems) of which when not properly catered for, the facilities will be imperfect. Also, inadequate integration between road and urban storm water drainage can be attributed to natural causes such as intense rainfall, flat topography and poor soil infiltration or man-made causes such as improperly laid and graded street, poor and inefficient drainage facilities that aggravate the flooding problem (Jimoh, 2008).
Most cities in Nigeria including Ibadan, the capital of Oyo State are faced with issues like poor drainage systems (Offiong et al., 2009) and water tight structures which result to flooding (Belete, 2011). Urban flooding which is the inundation of land or property in a built environment, particularly in more crowded areas are caused by rainfall overwhelming the capacity of drainage systems. Although this is sometimes caused by events such as flash flooding (Tucci, 2001).
Urban flooding is a condition characterized by its repetitive and systemic impacts on communities whether or not the affected communities are located within floodplains or near any body of water (CNT, 2013). Lagos, Calabar and Ibadan were revealed by Sule (2001) as cities where houses are constructed directly on drain channels and that this practice has resulted to blockage of storm drains and as a result leads to overflow and flooding of streets during the rainy season in Nigeria.
Also, poor drainage systems in Lagos State have caused tremendous environmental challenges. These menaces are primarily attributed to poor maintenance of drainage system and flood which can cause environmental hazards as a result of pollution. Some places were flooded, making the roads practically impassable for motorists. In many instances, torrential rainfall literally submerged the cities, halting human and vehicular activities thereby forcing residents to stay indoors as a pre-emptive measure against human disaster. Therefore, this study seeks to highlight the challenges of poor drainage system and flood control in Ibadan North metropolis.
1.2 Statement of the Problem
Government at all levels need to provide a lasting solution to the problem of occurrence of flooding which comes as a result of poor drainage in Nigeria, particularly in Ibadan North, the study area. The physical nature of Ibadan North and how it encourages flood occurrences in Nigeria needs to be fully understood by the government. Also, the diverse causes of flooding in Ibadan particularly in Ibadan North need the attention of the government. How these floods can be effectively controlled, eliminated or even avoided to avert its impact on human activities in the state must be a thing of concern to the government.
1.3 Research Objectives
This research is aimed at assessing the challenges of poor drainage system and flood control in Ibadan North metropolis. To achieve this, the following objectives are set for the research:
- To determine the factors that are responsible for flooding in Ibadan North metropolis
- To find out the flood prone areas in Ibadan North metropolis.
- To assess the major impacts of flooding in Ibadan North metropolis.
- To study with a view to establishing reliable control and management measures of flood hazards in Ibadan North metropolis.
1.4 Research Questions
The following are some of the questions which this study intends to answer:
- What are the factors that are responsible for flooding in Ibadan North metropolis?
- Where are the flood prone areas in Ibadan North metropolis?
- What are the major impacts of flooding in Ibadan North metropolis?
- What are the reliable control and management measures of flood hazards in Ibadan North metropolis?
1.5 Significance of the Study
Findings from this study will be significant to government, town planners, ministry of environment and the society at large. It will help to identify causes and sources of flooding in Ibadan especially in Ibadan North metropolis and the whole of Oyo State. The study will also help to assess the effects and discomfort that flood can have on individuals. It will enlighten the public on the dangers of floods and its destructive nature on life and property. It will as well serve as a base for more research work on the problems and prospects of flooding in urban Areas of the world.
1.6 Scope of the Study
This study is designed to assess the challenges of poor drainage system and flood control in Ibadan North metropolis. The focus of this study shall be on the prevalence of poor drainage system and flood control in Ibadan North metropolis
1.7 Limitation of the Study
The Major Limitations of the study are:
Cost Limitation: There was a cost limitation. This means that we could not offer any gift or monetary incentives for the respondents to answer the questionnaire. This might have resulted in certain prospective respondents choosing not to respond to the questionnaire. This might not have created a motivation among respondents not to take a chance to give opinions. Time Limitation: There are two types of time limitation faced during the study. The study was done for a period of four weeks. Hence the results would reflect the impact of the time constraint. The insights of the respondents were observed during the period of study. A more extensive study conducted over a larger time period or during a special period of time like when there were higher numbers of issues, can include insights from respondents employees over a broader time period and can bring in further depth into the research.
1.8 Definition of Terms
The following terms were used in the course of this study:
Drainage: the natural or artificial removal of a surface's water and sub-surface water from an area.
Flood: is the inundation of land or property in a built environment, particularly in more densely populated areas, caused by rainfall overwhelming the capacity of drainage systems, such as storm sewers.
