infrastructure development to mitigate future flood hazards (Adeoye et al., 2009; Adelekan, 2016; Nkwunonwo
et al., 2020; IPCC, 2022; Ajibade et al., 2020; UN-Habitat, 2021).
Many urban areas suffer from lack of adequate drainage infrastructure, drainage channels are often undersized,
blocked by waste, or poorly designed for increasing rainfall (Adelekan, 2016). This disrupts water flow, reduces
infiltration, and increases runoff, elevating flood hazards (Douglas et al., 2008). Wetlands naturally absorb
rainfall and mitigate weather events (IPCC, 2022), but urbanization has led to deforestation, soil compaction,
and impervious surfaces, reducing ecosystem functions (Nkwunonwo et al., 2020). Loss of wetlands increases
peak flood discharges and duration during rainfall (Ajibade et al., 2020) and leads to environmental degradation,
biodiversity loss, water pollution, and climate disruption (UN-Habitat, 2021).
As cities expand into ecologically sensitive areas like floodplains, the ability to absorb rainfall decreases, and
inadequate infrastructure heightens vulnerability (Douglas et al., 2008; Aderogba, 2012). Impervious urban
surfaces reduce groundwater recharge and increase runoff, often causing flash floods in the absence of
sustainable drainage (Adelekan, 2010; Abaje et al., 2018). These risks are worsened by the lack of integrated
land-use and flood risk policies. Marginalized populations in informal settlements near rivers are
disproportionately affected and excluded from planning processes, increasing their vulnerability (Ajibade et al.,
2013). Scholars call for climate-resilient urban planning that integrates environmental, hydrological, and social
data, which is crucial for fragile systems like those in Benue (Douglas et al., 2008; Adelekan, 2012).This study
examines urbanisation as a factor of flooding in developing countries within the framework of, the role of urban
expansion in exacerbating flood risks, analyzing spatial growth patterns and their impact on flood vulnerability
through an integrated approach combining geospatial analysis and hydrological assessment. Nigeria has also
witnessed increasingly frequent and severe urban flood disasters in recent years, largely due to unchecked urban
growth and inadequate flood management (Jinadu, 2015; Aliyu & Suleiman, 2016).
METHODOLOGY
This study employed a mixed-methods research design combining descriptive and analytical approaches to
understand patterns of urban expansion and flood vulnerability in Makurdi. The descriptive approach
documented land use changes, population trends, and flood events, while the analytical approach interpreted
spatial data and survey responses. The study used spatial data of (1976–2016), and socio-economic information.
Structured questionnaire captured household flood experiences, housing conditions, and coping strategies. In the
absence of hydrological tools, long-term residents (20+ years) provided perception-based indicators on flood
frequency and water levels. Using Israel’s (1992) formula, a sample of 400 households was drawn from an
estimated 61,784 households (2016 population estimate). A multi-stage sampling method was applied -
Stratification into high, moderate, and potential flood-risk zones. Purposive selection of two communities per
zone. Random selection of households (≈66 per community). Communities included Wadata, Wurukum, Idye,
Ankpa Ward, Agan, and Modern Market.
RESULT AND DISCUSSION
The data collected speaks to critical issues necessary for understanding the urbanisation factor of flooding in
Makurdi, the capital of Benue state, Nigeria. The discussion is anchored on the objectives of the study which
basically situates in the realm of urban spatial expansion, population growth and the emerging spatial pattern of
vulnerability in the city.
Urban Expansion and the Spatial Pattern of Flood Vulnerability in Makurdi
Urban expansion in Makurdi has been driven primarily by rapid population growth and extensive horizontal
development. As in many urban centres across Sub-Saharan Africa, this growth has translated into the physical
expansion of built-up areas, often at the expense of vegetation and natural drainage systems. The data presented
in this study show a strong correlation between population increase and spatial growth, both of which have
contributed to the city’s heightened exposure to flooding.
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