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Main causes of urban flooding in the Lagos area of Nigeria showing global climate change, poor urban planning, urbanization, and anthropogenic activities. 

Main causes of urban flooding in the Lagos area of Nigeria showing global climate change, poor urban planning, urbanization, and anthropogenic activities. 

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Urban flooding has been and will continue to be a significant problem for many cities across the developed and developing world. Crucial to the amelioration of the effects of these floods is the need to formulate a sound flood management policy, which is driven by knowledge of the frequency and magnitude of impacts of these floods. Within the area...

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... by flood water (IFRC, 2011; Oladunjoye, 2011). From a historical perspective, Lagos has always been sus- ceptible to various types of flooding which are well docu- mented from the 1960s onwards (Odunuga, 2008; Oyebande, 1974; Etuonovbe, 2011). However, in recent years pluvial flooding events (rainfall-related), have arguably been more widespread (Olajuyigbe et al., 2012). With the exception of 1973, the drought year, flooding in Lagos has occurred annually (usually between July and October rainy season) with an increasing intensity and an increased severity of impacts from 1960 onwards (Oyebande, 1974). According to FME (2012), Lagos is one of the few locations in Nigeria with more frequent flooding events (see Fig. 2). A number of floods have occurred in the Lagos area, although keep- ing track of events in the Nigerian context is challenging due partly to lack of relevant data collection capacities. As a result, data relating to hydrodynamics and historical flooding events are often lacking (Ajibade et al., 2013). According to previous studies, more severe flooding has been recorded in select areas of Lagos including Lagos Island, Apapa, Ikeja, Mushin, Surulere, and parts of Ikorodu (Oyebande, 1974; Odunuga, 2008). There is no clear explanation for this pe- culiar circumstance, but it seems to follow a pattern of spatial and temporal distribution of rainfall within and around Lagos. Table 1 shows a summary of major flooding events and associated consequences in the Lagos metropolis of Nigeria from 1968 to 2012. These data which appear to repre- sent generalized flooding situations were obtained from a wide range of sources including EM-DAT and the Nigerian FME (Federal Ministry of Environment). It is argued that the conclusions that can be drawn about flooding in Lagos from these data sets relate to events of higher magnitudes and return periods (Guha-Sapir et al., 2013). Only journalis- tic and non-quantitative evidence is available for lesser impacts and more frequent flooding events (see for example, IFRC, 2012). The problem with these forms of evidence is that they often do not have ethical and empirical groundings. For most of the events considered, data relating to flood duration and impacts in terms of number of people displaced, mortality, and economic losses were not available. On the basis of this inconsistency, the effectiveness of flood management policies is being queried (Adelekan, 2015). In many cases, different types of flood damage were aggregated. In- deed, this situation adversely affects accurate flood damage estimation since a critical understanding of Lagos flood risk in the context of flood damage typology is difficult. To qualitatively identify risk levels in this area, an approach used in the 2005 World Bank Hotspot project was adopted (Dilley et al., 2005). In this approach, records of flood events and affected areas were coupled with the population density of the local enumeration areas in Lagos and mapped in a GIS. The result of this analysis as shown in Fig. 3, indicates that Ajeromi-Ifelodun and Mushin areas are at a higher risk of flooding than other areas. This approach, regardless of its simplicity, offers a potentially valuable in- sight into flooding patterns in Lagos. However, much uncertainty lies within the results and this suggests the need for more detailed research that will investigate the flood risk lev- els at Lagos using a more detailed quantitative or qualitative data set. Over the past 2 decades, the causes of flooding in Lagos have received significant attention in the literature (Ayoade and Akintola, 1980; Action Aid, 2006; Adeloye and Rustum, 2011; Adelekan, 2013; Aderogba, 2012a; Oshodi, 2013; Ajibade et al., 2013, 2014; Soneye, 2014). Debates aris- ing from the literature indicate that Lagos floods are mainly the consequences of climate-change-induced short-duration- high-intensity or long-duration-low-intensity rainfall (Houston et al., 2011). This is unsurprising considering that climate change has arguably influenced regional precipitation patterns in recent history. Odjugo (2006) concluded that there are now more high-intensity short-duration rainfall events and more low-intensity long-duration rainfall events than there were 3 decades ago. Other factors have also been investigated with reference to the causes of these floods in Lagos. These include the topography of the area, land use (LU) and land cover (LC) modifications, and influence of canals, lagoons, and beaches (Aderogba, 2012a; Aderogba et al., 2012; Odunuga, 2008). Other factors considered are urbanization and population growth, poor urban planning, and poor environmental management and the indiscriminate disposal of solid waste (Lamond et al., 2012; Adeloye and Rustum, 2011). It is also suggested that tidal and co-tidal influences and frequent incursion from the Atlantic into the low- lands during heavy storms also play important roles (Ojinnaka, 2013). These factors (schematized in Fig. 4), seem to influence the occurrence of the hazard and the exposure of elements at risk. However, in relation to the vulnerabilities of social systems to flooding in the area, the development of slum settlements and poor perception of flooding among local communities, urban residents and the general public are critical factors (Agbola and Agunbiade, 2007; Nkwunonwo, 2013; Ayoade and Akintola, 1980; Odunuga et al., 2012; Oloke et al., 2013; BNRCC, 2008). To date, flooding in Lagos is characterized by severe consequences, which raise concerns about a lack of early warning and evacuation systems. Impacts from flooding (as illustrated in Fig. 5) are compounded by population density and the up- ward trends of urban growth in the area (Aderogba, 2012b). Also, flood water depth, inundation extent and duration as well as water flow velocity play contributory roles. The general impacts (such as displacement from homes, mortality, physical injuries, disruption of economic activities, destruction of urban infrastructure, and submergence of buildings) that relate to social systems directly have been extensively considered in the literature (Ugwu and Ugwu, 2013; Adigun et al., 2013; Ajibola et al., 2012; Aderogba, 2012b; Olajuyigbe et al., 2012). However, there are reports that Lagos flooding causes severe additional impacts including the loss of social values, spread of vector-borne diseases, as well as air and water pollution (Adelekan, 2010; Olajuyigbe et al., 2012; Bashir et al., 2012). Olajuyigbe et al. (2012) report that flood hazard increases city-wide poverty as a result of the farmlands which are de- stroyed and essential services which are often interrupted. Adelekan (2010) investigated these impacts using four poor urban communities in Lagos as case studies and identified three significant scales: individual, household, and community. At the individual scale, the reluctance of friends and family to visit one another while in flooded houses affects social relationships. This has broad adverse implications on community lifestyle and further compounds depression among flood victims in Lagos. Food insecurity is equally an important issue at this scale as food items stored in individual homes are often lost during flooding. In addition, there can be numerous health impacts including chronic skin infec- tions from exposure to contaminated environmental systems and increased effects on those with an already poor health history. Household and community scales of impacts are mainly indicated by the secondary effects of flooding in Lagos. Household impacts include deterioration of building qual- ity, intrusion of contaminated water into apartments, lack of good drinking water, and loss or damage to household properties including sanitation facilities. The community impacts include an unclean environment, disruption of movement, and damage to public utilities. Urgent needs arise where community schools were flooded and schooling for children has been interrupted. This is an important issue within the context of human development. In many other DCs where it is also applicable, community leaders and the local authorities have often instigated measures to ensure that children’s schooling is not interrupted despite the magnitude of flooding. In Bangladesh for example, a strategy known as “float- ing schools” in which classrooms are constructed on boats is being put in place during flooding (Huq and Aslam, 2003). This enables provision of uninterrupted education for children who have been impacted and whose education has been disrupted by flood catastrophes. The impacts of flooding in Lagos also trigger concerns for environmental management, urban sustainability, and the development, governance, and the vulnerability of urban residents and local communities. Other factors of concern are humanitarian needs and services, especially primary health delivery (Soneye, 2014; Ajibade, 2013; Lamond et al., 2012). Needless to say, concerns for solid waste management are crucial as long as the indiscriminate dumping of wastes into drainage systems remains prevalent within Lagos. One example of this is the water sold in polythene sachets which is the major source of drinking water for residents. It is perceived that many residents dispose of the containers which end up in drainage facilities. Being a non-degradable waste, it accumulates over time and blocks these drainage facilities. Unfortunately, little has been done to address such an important issue in flood control management. Despite the frequency of occurrence, causes, and severity of impacts of Lagos urban flooding alongside the understanding of a potentially increased risk in the future a better understanding of flooding in Lagos is lacking. Whilst most of the data relating to these impacts are at local levels and limited to small geographical areas, wide-ranging cross- disciplinary intervention measures are constrained. Lack of data and poor data scale present an ...

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... Apart from these factors, studies also show that poor perception about flooding among the local communities, poorquality construction materials and non-adherence to flood warning, cultural/ ethnic affinity, and weak institutional framework contributes to the menace of flooding (Ayoade and Akintola 1980;Oriola 2000;Odunuga et al. 2012;Nkwunonwo 2013, Nkwunonwo et al. 2016Unaegbu and Baker 2014;Hula and Udoh 2015;Ibrahim and Abdullahi 2016;Oladokun and Proverbs 2016;Olanrewaju et al. 2019). The devastating impacts of flooding are enormous. ...
... Regarding flood management approaches, various countries have adopted different flood mitigation strategies such as channelization, natural and artificial barriers against water surges (Few 2003;Schanze 2006;Miceli et al. 2008;Sayers et al. 2013 andAdelekan 2016). The non-structural measures include flood risk mapping, land use zoning and planning, flood vulnerability assessment, floodproofing, and flood (Nkwunonwo et al. 2016). Other non-structural measures that have proven very effective in flood mitigation include institutionalization of policies, flood awareness campaign, flood insurance, community-based adaptation strategies at the grassroots, early warning flood forecasting, relocation of properties, resettlement of human population, and green infrastructure planning (Price and Vojinovic 2008;Merz et al. 2010;Jha et al. 2012;Smith 2013;Dhiman et al. 2019). ...
... A major environmental challenge in the region is fluvial flooding due to the low-lying nature of the state (Odunuga et al. 2012;Kaoje and Ishiaku 2017). The minimum ground elevation in the study area is about 6 m (approximately 20ft) above sea level around Surulere, while the highest point is at Ifako-Ijaiye, measuring about 80 m (approximately 260ft) (Nkwunonwo et al. 2016). According to NPC (2006), the area's population is estimated at 3,057,956, with an approximate density of 140,566/km 2 . ...
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Human vulnerability to disasters poses a significant concern to water resources management. The present study examined the factors influencing the occurrence of flooding, risk and management strategies in Lagos, Nigeria. A set of questionnaires was administered to 400 respondents in four randomly selected settlements in Lagos State based on perception and observation methods. Descriptive and multivariate statistics and cartographic mapping techniques were employed for data analysis. The result indicates that the majority of the respondents live in a rented room and parlor. The significant flood risks include poor sanitation, a breeding site for mosquitoes, water contamination/waterborne diseases, and mental stress. Factors analysis explains 74.62% of the variance, indicating anthropogenic, natural, and institutional factors influencing flooding in the study area. The dominant flood management measures are clearance of drains, environmental sanitation, public awareness, training/education, while the significant steps taken by the government to ameliorate flooding challenges in the area include awareness, early warning, and education. The study concluded that there exists a significant difference in the factors influencing flooding across the settlements based on the ANOVA result given as: (DWSD F = 19.661, p < 0.05; RI = 41.104, p < 0.05; WIC = 18.123, p < 0.05; HWL = 37.481, p < 0.05; SD = 10.294, p < 0.05). The study contributes to knowledge using cartographic techniques to map the risks of flooding for easy understanding. The study has potential policy implications for planning and interventions in areas vulnerable areas. The study recommended monitoring of construction activities, enforcement of building codes, awareness campaigns, and early warning flood technology for sustainable flood management in the area.
... The replenishment of the surface/sub-surface water demands as well as its abundance leading to surface accumulation is significantly related to the rainfall received. Besides the amount of rainfall and its intensity, the local physiography and urban structures exert a definite influence on the nature and magnitude of surficial flow of rain water in the city and its surroundings (Pappas et al. 2007;Tingsanchali 2012;Nkwunonwo et al. 2016;McGrane 2016;Bhattacharjee et al. 2021). ...
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... Nigeria's flooding is mainly rainfall-induced and compounded by a host of anthropogenic factors tied to poor governance (Agbola et al. 2012;Odufuwa, Adedeji, and Oladesu 2012). At the same time, evidence suggests the flooding in Nigeria can be effectively averted or controlled by putting in place and implementing a suitable integrated flood risk-management strategy (Adelekan 2016;Nkwunonwo, Whitworth, and Baily 2016). Figure 5 highlights the areas of Nigeria prone to flooding. ...
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Disasters annually ravage numerous African countries. Flooding is the most severe and prevalent adverse event and has serious implications for sustainable development. As the world is currently facing the COVID-19 pandemic, disasters such as flooding are still occurring but limited attention is being paid. This research analyzes the cause of flooding in Nigeria and Ghana, two countries regularly affected by floods. Previous analysis of the causes of flooding has mainly been done on a national scale. This work adopts a transnational approach by studying the flooding phenomena in both countries. It highlights an opportunity for international partnership in disaster-risk reduction (DRR) as both Nigeria and Ghana are signatories to the Sendai Framework for Disaster Risk Reduction that advocates an understanding of disaster risk and aims to foster international cooperation. Appreciating the root causes of flooding is the first step in building awareness of the common problem that could be the foundation of seeking and adopting solutions. A systematic review of peer-reviewed papers was conducted. This study finds that the underlying drivers of flooding are similar in the two nations and advocates research and data-sharing as ways of partnering to tackle the common problem. This finding has the potential to promote and facilitate capacity building for DRR and flood-risk management (FRM). Potential solutions could also be scaled to other countries of comparable profiles facing related flooding challenges. This approach is likely to yield better and quicker results while presenting opportunities for partnership in achieving the United Nations 2030 Agenda for Sustainable Development that has already suffered COVID-19-related setbacks.
... There has been an increasing impacts of flooding events in Lagos state Nigeria. According to Nkwunonwo [14], a severe occurrence of flooding event of July 2011 affected approximately 5000 individuals (both dependent and working-age group) while 25 deaths were recorded due to the flood event. Public infrastructure such as bridges, schools and road networks, as well as residential houses were all inundated and destroyed by floodwater [15,16]. ...
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Flooding is one of the natural hazards affecting various parts of Nigeria, causing loss of life, impeding health, and disrupting human livelihood. This paper seeks to address the flooding issue by using geospatial analysis to model flood susceptibility in Amuwo Odofin Local Government Area of Lagos State. A multi-criteria method was adopted, using parameters such as rainfall, distance from rivers and streams, land use and slope. The flood susceptibility map produced from the analysis indicates the fourlevels of risk to flooding (very high, high, low, and very low-risk levels) at different locations of the study area. The findings revealed that Amuwo Odofin covers about 171.19 sq km, 10 percent of which fall within the very high-risk zone, while the high-risk zone covers 50 percent of the total area. The final map shows that locations nearer to the water bodies and within low terrains are susceptible to flooding. The communities within the very high and high-risk zones include; Iyagbe, Ibese, Isunba, Irede, Kirikiri, Aiyetoto- Asogun, Elachi, Isuba, Olute, Satellite town, Alapako, Amuwo, Agboju. Communities at lowrisk zones include Ijegun, Iseri- Osun, Ijagemo. Notably, roads and buildings will be flooded if the right actions are not taken on time. These findings are vital for appropriate government agencies such as town planners, civil society, emergency management agencies and other key stakeholders who can implement preparedness, evacuation planning, and early warning to settlements within the inferred flood risk zones.
... System (GIS), disaster mapping, remote sensing technologies, flood modeling, drainage systems and institutional approach of command and control by NEMA were discussed in literatures (Oshodi, 2013, Odunuga, 2008, Adeaga, 2008, Olorunfemi, 2011, Adelekan, 2013, NIHSA, 2013, Soneye, 2014, Nkwunonwo et. al, 2016. ...
... (NDRP, 2002). Other stakeholders involved include: international donor agencies, non-governmental organisations, works departments, health officials, Red Cross, Military and paramilitary units, police, fire fighters, Ministry of Environments, private sectors, communities, civil society and volunteers (Adelekan, 2013, NEMA, 2010, Nkwunonwo, et al., 2016. ...
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There is an upsurge in global migration, this is evident in the increasing number of people migrating from rural habitats to urban locations as a result of the existing socio-economic inequality between the rural and urban spaces. In Nigeria, the issue of migration-urbanisation is fast aggravating, which has earned it a front row in the country’s human development agenda. However, there is paucity of works in the literature that focus on the drivers of the nexus between urban migration, urban mobility and regional development and the need to know the extent of the effect of such movement. While it is debatable that the migrant’s productivity increase with transition to urban areas, studies are yet to determine the overall impact on human capital development, what extent does it impact on the host city, the rural community and the nation at large? The study examined the impact of urban mobility on regional development from 1995 to 2016 using the error correction method and found out that rural-urban mobility has a negative and significant effect on regional development. The study recommends that there is need to check rural-urban migration by developing development policies that provide for equitable development between rural and urban centres. This would go a long way in reducing negative consequences of urbanisation such as poverty, crime, poor housing, and unemployment among the legion of challenges of urbanisation caused essentially by the uncontrolled rural urban migration in a less developed country like Nigeria. Keywords: Migration, Regional Development, Rural Areas, Urbanisation, Urban Mobility.
... On the one hand, for Nigeria, there are reviews on the impact of floods on Nigeria's achievement of the sustainable development goals (Echendu 2020), on sustainable FRM-practices in flood-prone areas of Nigeria (Cirella and Iyalomhe 2018), on the challenges and opportunities of FRM in Nigeria (Oladokun and Proverbs 2016), and on the National Disaster Management Framework of Nigeria (Olanrewaju et al. 2019). For the city of Lagos in Nigeria, review papers examined the FRM practices of public and private actors (Adelekan 2016) and factors relating to the flood hazard, exposure and vulnerability, and challenges to reducing them (Nkwunonwo et al. 2016). On the other hand, for Ghana, there are reviews on current flood risk management practices as well as gaps and opportunities for improving resilience (Almoradie et al. 2020) and on emerging trends in FRM in the country (Ahadzie and Proverbs 2011). ...
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Flood events in West Africa have devastating impacts on the lives of people. Additionally, developments such as climate change, settlement expansion into flood-prone areas, and modification of rivers are expected to increase flood risk in the future. Policy documents have issued calls for conducting local risk assessments and understanding disaster risk in diverse aspects, leading to an increase in such research. Similarly, in a shift from flood protection to flood risk management, the consideration of various dimensions of flood risk, the necessity of addressing flood risk through an integrated strategy containing structural and non-structural measures, and the presence of residual risk are critical perspectives raised. However, the notion of "residual risk" remains yet to be taken up in flood risk management-related academic literature. This systematic review seeks to approach the notion of residual risk by reviewing information on flood impacts, common measures, and recommendations in academic literature. The review reveals various dimensions of impacts from residual flood risk aside from material damage, in particular, health impacts and economic losses. Infrastructural measures were a dominant category of measures before and after flood events and in recommendations, despite their shortcomings. Also, spatial planning interventions, a more participatory and inclusive governance approach, including local knowledge, sensitisation, and early warning systems, were deemed critical. In the absence of widespread access to insurance schemes, support from social networks after flood events emerged as the most frequent measure. This finding calls for in-depth assessments of those networks and research on potential complementary formal risk transfer mechanisms. Supplementary information: The online version contains supplementary material available at 10.1007/s10113-021-01826-7.
... This observation has been reported in many works of literature linking the cause of urban flooding in many residential parts during the rainy season (Njoku et al., 2013;Nwagbara and Okwuonu, 2016). Consequently, urban floods in some areas can deteriorate the quality of groundwater, when urban storm runoff collects surface contamination and deposit them in the ponds and groundwater recharge area where it infiltrates into the groundwater causing contamination (Nkwunonwo et al., 2016). The topographic index map predicts areas of high flow accumulation and it is an important tool that has been applied in different fields of natural resource studies. ...
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The impact of urbanization on the quality of drinking water sources is a challenge in many developing countries. In this research, the main source of drinking water was quantified, quality baseline defined, and a thematic decision support management tool developed to protect the quality using Aba, Nigeria. Data from primary and secondary sources were obtained from desktop search, empirical instruments, satellite data, hydrogeological investigations and water quality assessment. Geoscientific and statistical tools were used to analyse the landform, characterize the land use, and create management tools to protect the water source. The results revealed that groundwater is the main source of water for both domestic and industrial uses. An average water consumption per capita rate of 35.9 l/day was estimated, which is low compared to the WHO recommendation. The landform and land-use analyses revealed that the area is low-lying, poorly drained, and the urban land-use is the fastest-growing class growing averagely at 0.6% /annum between 1986 to 2017. Some of the urban land-use practices that harm the quality of the groundwater were identified and mapped in a contamination hotspot map. The results of the twenty-one quality indicators in the groundwater showed that the pH was acidic (3.7-5.6), total dissolved solids (TDS) ranged between 6.5 mg/l-364 mg/l. The mean concentrations of the remaining indicators were within the WHO limits for drinking water quality. But, the EC, TDS, chloride and nitrate revealed significant differences when tube-wells between densely and sparse built-up areas are compared. Again, four dominant water types were identified in groundwater. The Na-HCO3 water type was dominant mostly in the sparse built-up area and it is assumed as the background groundwater facies in the area. Whereas Mg, Ca-Cl, Na-Cl and Ca-HCO3 water types were predominant in the densely built-up area. The bacteriological assessments of drinking water from natural and alternative (i.e. beverages and packaged water) sources revealed the presence of E. Coli and Coliform bacteria in some samples of the natural water. The groundwater quality distribution and vulnerability assessment maps were developed based on water quality index, and DRASTIC methodologies, respectively. The quality distribution map showed that > 98% of the area has a “suitable“ rating. While the vulnerability assessment map found that the groundwater has a “medium” baseline vulnerability covering about 80%. The differences in the results were due to some observed poor urban land-use practices in the area. Finally, a thematic decision support tool that delineates priority monitoring zones and suggests possible source protected areas tailored for the area was developed. This tool is cost-effective in protecting the groundwater quality and can be applied to other developing urban areas with similar physiological conditions.
... Areas with high slopes and floodplains are developed (Dube et al., 2018;Adelekan, 2010;Amoateng et al., 2018). Building on floodable areas also occur because people cannot afford to buy land in safer areas (Nchito, 2007;Sakijege et al., 2012;Musungu et al., 2016;Kabanda, 2020) or because they do not perceive the hazard (Oruonye, 2013;Nkwunonwo et al., 2016). Rapid spatial expansion accompanied by the destruction of vegetation generates new hazards which include landslides, and along with waste dumping in rainwater drainage channels, increase the occurrence of flash floods (Doodman et al., 2017, p. 8;Douglas, 2017). ...
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The current literature links flood exposure and the consequent damage in the sub-Saharan Africa to urban expansion. The main implication of this pertains to the fact that cities are the target of flood risk reduction. However, our knowledge of the built-up area expansion–flood damage nexus is still too scarce to support any risk reduction policy at the local scale. The objective of this study is to reconsider the link between urban expansion and flood damage widening the observation to rural settlements with open access information alternative to global datasets on flood damages and moderate resolution satellite images. Using very high-resolution satellite images accessible via Google Earth Pro, the expansion of 122 flooded settlements in the Dosso region (Niger) during the past 20 years is evaluated. Spatial dynamics is then compared with the rate of collapsed houses due to flooding. Finally, house collapses and retrofitting are compared. We discovered that cities expand at faster rates and with an opposite trend to that reported by the global datasets. However, hamlets and villages expand even more rapidly and suffer more house collapses than rural towns and cities. House consolidation is quicker than the settlement expansion but this is not sufficient to reduce damage from pluvial flooding. The proportion of the Poor to the total number of inhabitants in rural settlements is three times higher than that in urban settlements. Environmental justice is, therefore, not just an urban issue but a rural urgency.
... Several studies have linked urban expansion in Lagos, Nigeria, to flooding [17][18][19]. The area comprises islands of different water bodies, ranging from lagoons and beaches to creeks, making it naturally susceptible to flooding. ...
... The DFO reports flood events worldwide based on news, governmental, instrumental, and remote sensing sources and might be biased towards more significant flood events [71]. Table 3. List of recorded flood events in various locations within Lagos State from 1968 to 2020 compiled based on literature [19] and online news sources (e.g., Aljazeera, Arise News, GistNigeria by Channels, and Floodlist). ...
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Incessant flooding is a major hazard in Lagos State, Nigeria, occurring concurrently with increased urbanization and urban expansion rate. Consequently, there is a need for an assessment of Land Use and Land Cover (LULC) changes over time in the context of flood hazard mapping to evaluate the possible causes of flood increment in the State. Four major land cover types (water, wetland, vegetation, and developed) were mapped and analyzed over 35 years in the study area. We introduced a map-matrix-based, post-classification LULC change detection method to estimate multi-year land cover changes between 1986 and 2000, 2000 and 2016, 2016 and 2020, and 1986 and 2020. Seven criteria were identified as potential causative factors responsible for the increasing flood hazards in the study area. Their weights were estimated using a combined (hybrid) Analytical Hierarchy Process (AHP) and Shannon Entropy weighting method. The resulting flood hazard categories were very high, high, moderate, low, and very low hazard levels. Analysis of the LULC change in the context of flood hazard suggests that most changes in LULC result in the conversion of wetland areas into developed areas and unplanned development in very high to moderate flood hazard zones. There was a 69% decrease in wetland and 94% increase in the developed area during the 35 years. While wetland was a primary land cover type in 1986, it became the least land cover type in 2020. These LULC changes could be responsible for the rise in flooding in the State.
... Climate-related disasters continue to spread and affect the poorer populations in both urban and rural areas. It has been suggested that flooding is the most widespread climate extreme event that accounts for more than 40% of disasters globally (Nkwunonwo et al. 2016). It is also considered as the third most damaging disaster after storms and earthquakes (Wilby and Keenan 2012). ...
... According to the National Emergency Management Agency (NEMA), 363 people were killed, 5,851 injured, 3,891,314 affected, and 3, 871, 53 displaced due to the resulting floods. Similarly, it is has been observed that flood disaster happens to be more frequent in Kano, Niger, Adamawa, Oyo, and Jigawa states possibly due to influence of river Benue, Niger and Ogun (Nkwunonwo et al. 2016). ...
... In the interest of environmental justice and social equality and inclusion, it becomes imperative on local governments in developing countries to consider integrated and larger adaptation strategy that will tackle community level vulnerabilities and strategic efforts such as DIY as a means of achieving an inclusive adaptation to flood risk. The need to focus on flooding is very important as it has been identified as universal issue in global climate change risk which affects more people than any other form of disaster (Nkwunonwo et al. 2016;Salami et al. 2016). ...