Understanding Mass Wasting in Metropolitan Accra

Abstract

Metropolitan areas are one the fast-growing urban metropolis in Sub-Saharan Africa with respect to both demographic densification and expansion of the built-up environment. The sprawling nature of Metropolitan Accra has also resulted in various human activities such as settlement, stone quarrying, and sand mining. The resultant effect is the exhibition of signs of mass wasting in the metropolitan area for some years now. Mass wasting refers to the wide variety of processes that result in the downward and outward movement of slope-forming materials including rock, soil, artificial fill, or a combination of these. The study employed a mixed-method approach to ascertain the triggers of mass wasting in Metropolitan Accra. Specifically, the study assessed the vulnerability levels, residents’ perceived risk to mass wasting and presented some recommendations for policy considerations. A total of 130 respondents were used for the study: 124 household survey and 4 in-depth interviewees. The results further showed that the main trigger for mass wasting as perceived by respondents in the study communities were anthropogenic factors with environmental impacts making majority of responds in relation to mass wasting. The results again revealed that respondents at the summit of hills perceived themselves to be less exposed to mass wasting than those along the slope and base of the hill thus respondents along the slope and base of the slope are perceived to be at greater risk of mass wasting events. The findings again revealed that, majority of the communities at the northern part of Ga South were less prone to mass wasting compared to those of the southern part, exposed to high risk of mass wasting. Weija-Gbawe had some patches of areas very low to mass wasting with the interior part accounting for some major high-risk zones. The study suggested some recommendations for policy considerations to help manage the event.