The biggest city of Tanzania, Dar es Salaam, faces increasing flood
risk, causing frequent sickness, loss of life, and widespread damage
to property. Dar es Salaam is one of the fastest growing cities in the
world. More than 70% of the residents live in informal settlements.
Many of them are located in flood prone areas like river valleys and
floodplains, which flood annually. Because of their limited coping capacity,
residents are not able to recover from the impacts of this flooding.
Due to the change of precipitation patterns, the flood risk is
likely to increase in the future, putting even more people and assets at
risk during more frequent and intense floods. This graduation project
seeks to answer the main research question: How can urban form
and landscape help to mitigate the effects of floods on citizens in Dar
es Salaam, Tanzania?
For areas with a high density of buildings, multifunctional courtyards
are proposed. The existing building structure is strategically densified,
and filled with new buildings to shape courtyards. Inside, a variety of
interventions reduce the water run-off into the river valley, treat waste
water and generate income via urban agriculture and aquaponic
systems. For the river valley the construction of “chinampas” is being
proposed, which creates a high retention capacity for storm water
while enabling agricultural activities and connectivity across the river
valley throughout the wet and dry seasons. At the edges of the valley,
different interventions are located in order to reduce and clean
run-off water before entering the valley. The combination of spatial
interventions to reduce the flood risk with urban agriculture reduces
the impacts and increases the ability of residents to deal with future
hazards.
The design proposals are supported by a implementation strategy
and complimenting policies which reduce pollution, steer future urban
development and introduce new renting models to host a higher diversity
of lifestyles with different economic abilities.