Reviewing The Argument On Floods In Urban Areas: A Look At The Causes

The paper reviewed literature on the causes of floods in urban areas in order to establish direct links between the causes and floods using the city of Accra, Ghana as case study site. The systematic review process was used and involved 45 reports and peer reviewed literature 64% of which was based on work done in developing countries. The causes of floods were skewed towards finding solution to perennial floods in developing countries as against addressing secondary effects of floods in developed countries. There was lack of precision in describing the causes of floods. No common vocabulary was found in expressing the causes of floods, some of the phrases used were ambiguous, and the linkages to floods were either assumed or not clear. The review identified 24 causes of floods out of which 12 scored more than 10%. Heavy rainfall was the most frequently cited cause (62%) followed by urbanization 40%, inadequate drains 33%; poor waste management 31%, unplanned growth 24%, storm surge 24% and failure of infrastructure 22%. Other causes included poor engineering 16%, weak law enforcement 16%, development in flood plains 13% and poor maintenance of drains 11%. Climate change was cited by only 9% but its possible impact on urban development could be far reaching. The causes of floods were grouped into direct such as intense rainfall, increased imperviousness, and inadequate drainage. Indirect causes included poor waste management, sedimentation, construction in low laying areas, etc. Interventions to address flooding were suggested based on the three direct causes.