URBAN DEVELOPMENT AND THE INCREASING TREND OF FLOOD IN LEKKI, LAGOS STATE

CHAPTER ONE

INTRODUCTION

1.1 Background of the study

The global requirement for sustainable flood risk management arises from the scale and regularity of flood disasters, as well as their significant impact on people, properties, and the environment. This management is essential to reduce the persistence of towns and cities worldwide. According to estimates, nearly 200 million people in over 90 countries are exposed to the severe consequences of floods each year. This number is projected to increase in the future due to the effects of climate change and the growing impact of urbanisation on the population (United Nations/ New Partnership for Africa's Development (UN/NEPAD), 2017). There has been a concerning increase in both economic and social damages caused by floods in Nigeria in recent years. 

Flood risk refers to the likelihood of an area being flooded as a result of either a dam failure or an intense and prolonged period of heavy rainfall. This can pose a threat to both human life and property within the affected area (Nyakno, 2020). David (2018) and Wisner et al., (2019) defined disaster risk by considering the following components or concepts: hazard, exposure, vulnerability, and capacity measures. Risk is determined by three key factors: hazard, exposure, and the vulnerability of the element at risk. To effectively compare different areas or communities, it is necessary to measure risk and vulnerability using specific quantitative indicators. 

Consequently, flood risk threats arise from two sources: the natural environment (hazard and exposure) and the characteristics of local human activities (vulnerability) (Wisner et al., 2019). Some studies contend that global warming and climate change are directly or indirectly amplifying the amount of precipitation (rain and ice melting), resulting in an escalation of runoff magnitude. In addition to precipitation, various other natural elements contribute to the formation of surface runoff, which ultimately results in floods. These factors include geological features, land use, topography, soil properties, vegetation, and hydrological aspects (Ronnie et al., 2019). However, some individuals contended that human activity exerts an influence on the characteristics of the physical environment, and that the environment merely reacts to these actions (Daniel, et al., 2022). Anthropogenic influences encompass human activities such as faulty urban planning, improper waste management, insufficient drainage systems, indiscriminate trash disposal, development on flood-prone areas, and other unsuitable actions that disrupt the natural water flow.

Recent empirical studies have demonstrated a substantial correlation between urbanisation and flooding. The volume of runoff is primarily determined by the infiltration characteristics and is directly correlated with the proportion of an area that is covered by impermeable surfaces such as roofs, roadways, and other impervious surfaces during storm events (Ezekiel, 2019). Mandu (2019) contend that the collective consequences of human activities, disregarding the natural environment, have transformed recent floods from a natural occurrence into a calamity caused by human actions. In developing cities, the issue becomes even more pressing due to the lack of effective regulation of land use practices in floodplains and a deficient institutional framework for enforcing floodplain ordinances (Daniel, et al., 2022).

Urbanisation significantly contributes to the increased susceptibility of lower-income families residing in floodplains and flood-prone areas (Daniel et al., 2022). Urban expansion, characterised by population growth via natural increase and immigration, together with infrastructure and social development, intrinsically increases the likelihood of flood danger, particularly among the urban poor. If floodplains are encroached upon and vegetation covers are dislodged without appropriate spatial planning and management measures, it is inevitable that other problems, such as a high risk of flooding, will occur, especially in floodplain areas like Adelaide in 2023. Recent research has debunked the old assumption that natural factors alone cause flooding. It has been found that human activities are the primary cause of flood risk in many urban areas, such as Lekki, Lagos. These activities include clearing forests and vegetation without regard for the consequences, constructing buildings on floodplains, inadequate infrastructure development, and rapid population growth. These factors have undoubtedly worsened the problem of flooding in the city.

Lekki is seeing significant development and is considered one of the fastest-growing neighbourhoods in Lagos State. Lekki, originally a sparsely populated region emphasising natural ecosystems and tourism, has undergone a significant transformation into a vibrant metropolitan area (Roland, 2020). This transition encompasses the development of residential communities, commercial structures, and infrastructure developments such as roadways and bridges. Lekki's appeal for real estate development stems from its advantageous coastline position, which provides picturesque vistas and close proximity to Lagos Island, a prominent commercial centre (Roland & Bash, 2022). Urban development plays a crucial role in driving economic growth, especially in areas that are experiencing rapid expansion. Nevertheless, it frequently presents environmental obstacles, such as a heightened susceptibility to flooding (Luke et al., 2019). In recent years, Lekki, an upscale beachfront region in Lagos State, Nigeria, has undergone substantial urban expansion. Although this development has brought economic benefits, it has worsened the issue of floods, creating risks for both infrastructure and human well-being. This study aims to evaluate the correlation between urban growth and the rising occurrence of floods in Lekki, Lagos state.

1.2 Statement of the Problem

The swift urbanisation in Lekki, a state in Lagos, has yielded substantial economic advantages and metamorphosed the region into a thriving metropolitan hub. Nevertheless, this swift process of urbanisation has also resulted in a pressing environmental concern: the escalating occurrence of flooding. The recurrent and intense inundations in Lekki in 2024 have underscored the pressing necessity to tackle the difficulties linked to urban expansion and its repercussions on the environment.

Wahab (2019) identifies Land Use Changes and Environmental Degradation as significant factors contributing to flooding in Lagos. The substitution of indigenous terrains with non-porous materials, such as cement and asphalt, has diminished the land's inherent ability to soak up precipitation, resulting in heightened surface water flow and an elevated likelihood of flooding. Punch (2024) states that one of the main causes of repeated floods is the construction of buildings on floodplains and the lack of sufficient drainage systems, as highlighted by specialists. The implementation of extensive sand filling and land reclamation projects disrupts the natural hydrological processes, leading to the exacerbation of flooding problems (Akim, 2023). Vegetation depletion has been identified as a causative cause for various environmental problems, such as flooding, soil erosion, diminished air quality, and loss of biodiversity (Biodun et al., 2023). 

The occurrence of flooding in Lagos has adverse effects on human health due to the pollution of water bodies and the rise in cases of waterborne illnesses such as malaria, cholera, typhoid, yellow fever, diarrhoea, leptospirosis, and hepatitis A (Echendu, 2020; Olanrewaju et al., 2019). The persistent discharge of untreated sewage and trash into the environment has resulted in the contamination of wells and boreholes used for household water supply in Lagos. This further worsens the scarcity of clean water in the area (Olanrewaju et al., 2019; Atufu and Holt, 2018; Anabaraonye et al., 2021). Floods can affect water insecurity in Lagos through two mechanisms. Initially, it pollutes water infrastructure, including wells and municipal pipes, which provide drinking water to urban coastal neighbourhoods in Lagos (Adelekan, 2010; Echendu, 2020). Furthermore, floods in Nigeria exacerbate the issue of safe drinking water contamination, which is already a pressing concern. Currently, a staggering 63 million individuals in Nigeria do not have access to clean drinking water (Echendu, 2020). In Lagos, numerous people residing in informal settlements, which are very susceptible to flooding and have little financial resources, also face challenges in obtaining clean water and sanitation facilities (Aliu and others, 2021). Therefore, the necessity for this investigation arises.

1.3 Objectives of the study

The primary objective of this study is to critically evaluate Urban Development and the Increasing Trend of Flood in Lekki, Lagos State. Specific objectives of this study are to:

To evaluate the extent to which rapid urban development has contributed to the increased frequency and severity of flooding in Lekki.

To investigate the impact of land use changes, such as sand filling and land reclamation, on natural water flow and flood patterns.

To analyze the current state of drainage systems in Lekki and their capacity to prevent flooding.

To develop comprehensive strategies for improving flood management and resilience in Lekki

1.4 Research Questions

The following research questions which are in line with the objectives of this study will be answered in this study:

What is the extent to which rapid urban development has contributed to the increased frequency and severity of flooding in Lekki?

What is the impact of land use changes, such as sand filling and land reclamation, on natural water flow and flood patterns?

What is the current state of drainage systems in Lekki and their capacity to prevent flooding?

What are the strategies for improving flood management and resilience in Lekki?

1.5 Research Hypotheses

To determine the effectiveness of this study, the following research null hypotheses will be formulated to guide the study and it will be tested at 0.05% levels of significance.:

Ho: The extent to which rapid urban development has contributed to the increased frequency and severity of flooding in Lekki is low.

Ha: The extent to which rapid urban development has contributed to the increased frequency and severity of flooding in Lekki is high.

1.6 Significance of the study

An in-depth analysis of urban growth and the rising occurrence of floods in Lekki, Lagos State, holds great importance due to its impact on urban planning, community resilience, environmental sustainability, policy-making, and overall societal well-being. The lessons it offers are valuable and can be applied not only to Lekki but also to other urban regions globally that are encountering similar issues. 

Moreover, the conclusions derived from these research have the potential to shape policy pertaining to land utilisation, water administration, and safeguarding of the environment. This can result in improved governance and more efficient mitigation strategies.

Moreover, upcoming scholars will utilise it as a thorough examination of the current body of scholarly works. Consequently, future students with an interest in studying this subject will have the opportunity to utilise this work as a dependable source of information that can be comprehensively evaluated.

1.7 Scope of the study

Broadly, this study focus is to critically evaluate Urban Development and the Increasing Trend of Flood in Nigeria. Specifically, this study seeks to evaluate the extent to which rapid urban development has contributed to the increased frequency and severity of flooding in Nigeria and investigate the impact of land use changes, such as sand filling and land reclamation, on natural water flow and flood patterns. Further, this study will focus analyzing the current state of drainage systems in Nigeria and their capacity to prevent flooding and it also seeks to develop comprehensive strategies for improving flood management and resilience in Nigeria.

The study is carried out in Lekki, Lagos state.

1.8 Limitations of the study

As is common in all human endeavours, the researchers faced minor limitations when conducting the study. The main limitation was the lack of extensive literature on the subject, as there is limited data available for Urban Development and the Increasing Trend of Flood in Nigeria. Consequently, a significant amount of time and effort was necessary to locate the appropriate materials, books, or information and to gather data. 

Additionally, this study is constrained by its small sample size and narrow geographical scope, focusing just on Lekki, Lagos. Consequently, the results of this study are not applicable for generalization, thereby leaving room for further research. 

Additionally, the researcher's limitations were primarily due to financial constraints, as they are a student and do not have a source of income to sustain themselves. It was challenging to afford transportation expenses to and from the study location due to the high cost of transportation, which is influenced by inflation in Nigeria today.

Furthermore, the researcher faced a time constraint due to the need to do this research while also fulfilling the obligations of attending lectures and other educational activities.

1.9 Definition of terms

Flood: Flood is an overflow of water onto normally dry land. The inundation of a normally dry area caused by rising water in an existing waterway, such as a river, stream, or drainage ditch. Ponding of water at or near the point where the rain fell. Flooding is a longer term event than flash flooding: it may last days or weeks.

Flood risk: Flood risk is a combination of the probability (likelihood or chance) of a flood event happening and the consequences (impact) if it occurred.

Urbanization: Urbanization is the process through which cities grow, and higher and higher percentages of the population come to live in the city.