| dc.description.abstract | The Nairobi River basin riparian zone is critical to the ecological and hydrological
stability of Nairobi City County, Kenya. However, growing urbanisation, pollution, and
deforestation have reduced its ability to manage floods. The degradation of the riparian
zone has increased the frequency and severity of flooding in the city, demanding a
thorough investigation into the role of the Nairobi River basin riparian zone in flood
management. This study sought to assess the degradation of the riparian zone over 30
years (1991-2021), determine the relationship between degradation and flood
occurrences, and recommend long-term mitigation solutions. The hydrological cycle
theory, which elucidated how alterations in land use and climate patterns disrupted
natural water flow dynamics, exacerbating flood risks, guided the research. A
correlational research design was applied in the study. A sample size of 373 individuals
was chosen, comprising government officials, NGOs, and local inhabitants, using simple
random and selective sampling methods. Data collection tools included surveys,
interviews, GIS, and remote sensing technology. Inferential statistics were employed to
identify correlations and significance levels, with data analysis conducted using SPSS
version 25. The Nairobi River basin riparian zone has deteriorated significantly during
the past 30 years, with the built-up area expanding from 80.2 km² in 1991 to 275.5 km²
in 2021, mostly due to urbanisation and encroachment. The study found a significant
positive connection (r = 0.72, p < 0.05) between riparian vegetation degradation and the
frequency of floods. 52% of respondents reported annual floods, and 37% reported
biannual floods. Deforestation, pollution, and unregulated construction activities
significantly influenced flood occurrences (p < 0.01). Reforestation, riparian buffer
zones, and improved waste management are key sustainable mitigation techniques that
significantly lower flood risks (p < 0.05), according to regression analysis. Community
engagement and policy enforcement were also cited as crucial to successful
implementation. To conclude, the degradation of the Nairobi River basin riparian zone
is significantly linked to rising flooding. The report suggests that Nairobi City County
undertake stringent riparian zone management methods, like as afforestation and buffer
zone enforcement, as well as include flood mitigation strategies into urban design
frameworks. | en_US |
