Greater Accra Resilient and Integrated Development Project

Synopsis: HKV was assigned by the World Bank to develop an evidence-based investment plan for climate (flood) risk reduction in Greater Accra Region, Ghana, West Africa, resulting in a first phase 200 million USD loan. Currently, the government of Ghana is executing the flood risk reduction investment plan proposed by HKV.

The Greater Accra region in Ghana, West Africa, is affected by floods every rainy season. The area is densely populated and low-lying areas that are prone to floods are increasingly inhabited. The economy is fast growing, followed by rapid urban development. The existing drainage capacity is not sufficient anymore to safely discharge excess water and has even worsened due to siltation and solid waste piling up in the drains. High tides, the sea level rise and coastal erosion cause additional risks. The flood risk thus has increased rapidly, sadly demonstrated by the devastating flood of June 3rd, 2015, causing a low lying gasoline station to explode, killing over 200 people.

The World Bank commissioned a consortium of Dutch firms HKV (lead partner), Ecorys and Bosch-Slabbers, together with Acon from Ghana, to support evidence-based decision making and investment planning for climate risk mitigation in Greater Accra, based upon objective assessment of the cities’ climate hazards, vulnerabilities, and exposure. The setup of the assignment is outlined below.

HKV developed a detailed hydraulic and hydrologic flash flood model. Despite a lack of ground data, the model was validated thoroughly, using data from (social) media, testimonies of Ghanaian specialists and satellite data. HKV also developed a flood damage model that was validated on the 2015 flood damage estimation executed by the World Bank specialists and Ghanaian officials. These models were used as input to a decision framework, where costs, benefits, different impacts and other relevant criteria were assessed, supporting relevant institutions in Ghana in setting up an investment plan for flood mitigation.

The government of Ghana and all stakeholders were intensely involved in this decision-making process, headed by a Steering Committee. The assignment resulted in an investment plan, that was presented to the government of Ghana and approved by the board of the World Bank in May 2019, resulting in a 200 M$ government loan. Currently, the government of Ghana is executing the flood risk reduction investment plan.