SUITABLE SITE SELECTION OF RESIDENTIAL AREA FOR URBAN EXPANSION BASED ON GEOSPATIAL TECHNOLOGY: THE CASE OF AREKA TOWN, SOUTHERN ETHIOPIA

Abstract

Cities are one of the most dynamic systems on the planet. Rapid urbanization demands careful planning to avoid severe environmental and socioeconomic consequences. Modern Geographic Information Systems (GIS) and Remote Sensing technologies have opened up a world of possibilities, and tremendous progress has already been made in monitoring and regulating rapid urban growth. The main objective of this study was to assess suitable site selection of residential area for urban expansion: the case of Areka town, Southern Ethiopia by applying geospatial technologies. Data were collected using satellite image, Aerial photo, town structural plan, field observation, ASTER image from Ethiopian Geospatial Institute with a spatial resolution of 20*20m for slope extraction, and land use land cover maps generated from land sat 8 images with spatial resolution 30m*30m was assessed using GIS tools and remote sensing techniques by supervised classification. To accomplish the objectives, the present study used factor maps as land-use/land-cover, soil map, slope, road network, river, public facility, and population density which were reclassified in GIS environment followed by preparation of the suitability map. The area has exhibited urban land use classes of the town aerial photograph of 2008 and revised structural plans of the town for 2014/15. Residential (27.78%) and special function (19.28%) were the most common urban land use groups in the town, followed by forest and informal green (9.87%), transportation and road network (9.81%), services (9.09%), manufacturing (7.40%), commercial (6.72%), and the rest (10.09%). The analysis reveals that since 2021 the residential site, represented by forest land, grass land, cultivated land, and open space have been transformed into other land uses. This has resulted in the decreasing of forest land, grass land, cultivated land, and open space. On the contrary, built-up area has been highly increased. Land use, soil, population density, road, slope, river, and public facility were all taken into account while selecting suitable residential locations for future planning purposes. As a result, around 1312 ha (37.64%), 959 ha (27.51%), 621 ha (17.82%), and 593 ha (17.03%) of the entire urban landscape are very suitable, suitable, moderately suitable, and unsuitable, respectively. The study significantly supports the utility of modern geospatial technologies for urban growth and expansion, as well as the identification of suitable areas for housing expansion based on the criteria listed above.