# 1 Background

The study explores the relationship between poverty and flood risk in Dar es Salaam. The focus is particularly on the role of poverty in exposure – who is affected by floods? – vulnerability – how much do people lose in floods? – and socioeconomic resilience – to what extent are the affected people able to cope with and recover from floods?

Dar es Salaam is East Africa’s largest city, and on some accounts Africa’s fastest growing metropolitan area. In 2012, the population reached 4.4 million – more than six times that of the next city, Mwanza – and the city is growing at a rate of 6.5% per year. Dar es Salaam will likely achieve megacity status (10 million plus population) before 2030 (TURP, 2015). The combination of high informality and climate hazards makes flood risk a critical challenge for sustainable urban growth and public health in the city (World Bank, 2017; Picarelli et al, 2017).

Tanzania is the most flood-affected country in East Africa,<sup>2</sup> and cities across the country are underprepared to meet the challenges of urbanization and increased vulnerability to climate-related hazards. Flooding is estimated to be the costliest hazard at the national level, causing 62% of losses from natural disasters from 1990 to 2014.<sup>3</sup> Tanzanian towns and cities have undergone a massive spatial expansion: an estimated 7080% of Dar es Salaam residents live in unplanned settlements, and in Mwanza, the second largest Tanzanian city, it is estimated that 81% of households in hazard-prone areas are also in the low-income population bracket (Hambati, 2013). Today, about 8% of Dar es Salaam’s total area is located in the low-elevation coastal zone below the 10m contour line, where exposure to floods is high (Kebede and Nicholls, 2011). These areas are typically characterized by limited access to adequate municipal services (water, sanitation, solid waste, electricity) and associated infrastructure, notably drainage. Only 13% of the city’s residents are served by adequate sewerage systems, and 37% of solid waste is properly collected. Together these contribute to a deterioration of environmental conditions, with people suffering consequences which include major health risks, particularly at times of flooding (World Bank, 2011; Hambati, 2013).

Estimations suggest that floods in Tanzania could threaten thousands of people and several billions worth of assets in the future. This report shows that the situation could be even worse. The national costs of climate-related hazards are estimated to be around 1% of GDP in recent years. With projected climate change impacts – higher temperatures and more unpredictable and concentrated rainfall - net economic costs due to climate change could reach 2 to 3% of GDP per year by 2030. In Dar es Salaam, floods in 2009, 2010, 2011, early and late 2014, 2015, 2017, 2018 and 2019 caused losses of lives, injuries, and severely impacted diverse sectors. These included transportation, energy and social infrastructure such as schools and health facilities (COWI et al, 2013). In 2005, models estimated the number of persons exposed to a 100-year coastal flood at 30,000 and the level of asset losses at US$35 million (Kebede and Nicholls, 2011). Studies estimating the impacts of climate hazards in Dar es Salaam have found that the city has infrastructure assets worth approximately US$5.3 billion at potential risk from projected flood impacts under climate change and sea level rise scenarios (Kebede and Nicholls, 2010). These results are driven by the lack of a coordinated storm water drainage system, inadequate housing development and blocking of water streams by careless dumping of solid waste (Sakijege, Lupala and Sheuya, 2012). Results from the current report indicate that far more people are affected by floods than the models predict.

At the household level, the poor are disproportionately affected by flooding, and often do not have the means to recover. This study is an attempt to quantify the impacts for households living in Dar es Salaam both inside and outside known flood risk areas. Vulnerable populations, such as children, elderly and

> 2 UN-Habitat 2014, using Global Urban Indicators, 2009 data. 3 PreventionWeb, accessed 19 February 2019.

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