Assessment of Urban Sprawl Using Geospatial Techniques in Awka Town, Anambra State, Nigeria

Abstract

Cities and towns in developing countries are experiencing an unplanned and uncontrolled development known as urban sprawl. This research examines urban sprawl in Awka metropolis, between 1986 and 2016. Landsat 5 Thematic Mapper (TM) of 1986, Landsat Enhanced Thematic Mapper plus (ETM+) data of the year 2000 and Enhanced Thematic Mapper plus (ETM+) 2016 were used for this study. Geographic Information System was employed for the analysis of the data. Result showed that Awka metropolis witnessed a remarkable growth between 1986 and 2016 from mere 3444.48 Km2 in 1986 to about 11,452.46 Km2 in 2016. This growth contributed to the sharp decline in farmland from 25,500.51 km2 (19.13%) in 1986 to 17,848.44 km2 (13.60%) in 2000 and further declined to 10,037.07 km2 (10.01%) in 2016. Bare surfaces witnessed an increase over the years of this study. This increase is as a result of clearing of natural vegetation for urban development, thereby exposing the land to direct contact with rainfall, leading to gully erosion in the area. Light vegetation also witnessed a sharp decreased from (38.53%) in 1986 to (8.53%) in 2000. It further decreased (8.53%) to (4.62%) in 2016. Therefore, increase in population led to the increase in urban sprawl in the study area. The study recommends that there is a need for a regular monitoring of urban sprawl and development in the study area by the state government especially with the aid of geospatial techniques for better decision making.