ASSESSMENT OF URBAN RIPARIAN ENCROACHMENT AND LEGAL PROTECTION MEASURES
A SPATIAL-TEMPORAL STUDY OF NAIROBI RIVER, KENYA
Abstract
This study examined the extent of urban encroachment along the Nairobi River riparian zone and assessed the effectiveness of existing legal protection measures. Using remote sensing and Geographic Information Systems (GIS), the study analyzes land use changes over a 30-year period (1992–2022), highlighting significant transformations in the riparian zone. Results reveal a dramatic increase in built-up areas, from 4.6% in 1992 to 21.7% in 2022, with a corresponding decline in vegetation (from 8.4% to 1.9%) and water coverage (from 56.3% to 51.7%). The study identifies rapid urbanization, lack of affordable housing, rural-urban migration, and inadequate enforcement of riparian protection laws as factors contributing to encroachment along Nairobi River Riparian Reserves. Furthermore, the study critiques the overlapping mandates of various institutions and the lack of clear legal guidance on riparian widths. The findings suggest that enhanced coordination among state agencies, improved enforcement, and the incorporation of remote sensing technologies in riparian monitoring are essential for effective management. Recommendations also include promoting affordable housing, decentralizing economic opportunities, and fostering community engagement to mitigate encroachment. This research contributes to the understanding of riparian zone management and offers actionable strategies for improving legal and institutional frameworks to protect urban riparian zones from further degradation.
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