Developing a Digital Surface Model of Urban Land Use Transformation in Upper Hill, Nairobi, Kenya

Abstract

Urban land use transformation is one of the main characteristics of urban growth. Understanding urban land use transformation and its impact requires information about growth trends and patterns among other important information. Geographic Information Systems (GIS)Technology plays a great role in understanding the process and trends of land use change, modelling current situation and possible future changes. Nairobi’s Upper Hill has transformed over the years from a residential area to a largely commercial area causing a major challenge on the existing infrastructure and provision of services. The area also lacks geo-information needed to guide infrastructure development and service provision. The study used Geographic Information System (GIS) to develop a 3D model to depict Urban Land use transformation between the years 2001, 2011 and 2021. Spatial and non-spatial data were obtained and analyzed to understand the change in the area. Geo eye images were obtained from google earth for the three epochs and land use change analysis done. The images were also used to obtain building footprints and 3D modelling done using procedural rules in ArcGIS City engine to visually depict changes between the three epochs. The study established that there was major transformation in land use between the three epochs resulting in an increase in built up areas and a decrease in the non-built-up areas. The greatest transformation in land use occurred between 2001 and 2011 accounting for 104% increase in built up areas and 28% increase in built up areas between 2011 and 2021. 3D GIS modelling revealed that the land use transformation from residential to commercial in the area is mainly characterized by high-rise building developments replacing the former low-density bungalows. The study demonstrated the role of Geographic Information System (GIS) in understanding and modelling urban land use transformation revealing both quantitative and visual changes. The study recommends the use of Geographic Information Systems (GIS) technologies to obtain information on urban issues such as urban land use transformation, improve comprehension and analysis and aid in making informed decisions.