Evaluation of the potential hydrological impacts of land use/cover change dynamics in Ghana’s oil city

Abstract

Ghana’s oil city—the Sekondi–Takoradi Metropolis—has rapidly urbanized over the past three decades. Combined with the effects of climate change, changes in land use and cover (LULC) threaten the hydrological cycle of the metropolis. It is, therefore, prudent to examine how the LULC change over time has impacted its watershed and the potential threats that such changes pose. This paper’s objective was to investigate and discuss the potential impacts of land development intensity (LDI) on the local hydrology of the metropolis, using remote sensing and GIS. Our results revealed interesting dynamics in the LULC changes in the metropolis that may have immensely affected and continued to impact the local hydrological cycle. Of the overall urban expansion in the metropolis, more than 50% occurred within its main watershed, which covers about only 35% of the entire metropolis. Urban expansion within the watershed occurred at the expense of forest and agricultural lands. The continual LDI increase in the watershed has potential significant hydrological consequences in terms of flooding, groundwater subsidence, and saltwater intrusion. To achieve sustainable water management, it is critical that policy decisions recognize and incorporate the potential impacts of LULC changes to limit future impacts.