Options for landscape based stormwater management and green infrastructure within urban areas in develoment countries – a case study of an informal settlement in Dar es Salaam, Tanzania
Description
Abstract:
Many developing countries are challenged by the negative impacts of climate change. In Tanzania the rain intensity is projected to increase This will create high risks of flooding especially in the urban centers. Dar es Salaam, Tanzania’s biggest city and economical center, is struggling with urban floods every year. Green infrastructure (GI) and sustainable urban drainage systems (SUDS) or so called Landscape Based Stormwater Management Systems (LSM) are being adapted in the developed world as alternative supplementary systems for handling excessive stormwater run-off and floods. In many developing countries the sewer systems are limited and in some areas drainage infrastructure is non-existent, this is also the case for Tanzania. Implementation of GI and LSM may help manage excessive run-off and help to reduce flooding and the impacts of flooding in urbanized cities in the developing world.
This thesis investigates the opportunities for implementing Green Infrastructure and Landscape Based Stormwater Management in a specific informal settlement in Dar es Salaam which is challenged by floods. The thesis is a case study of a specific informal settlement Kawe Ukwamani, which is located downstream of the Mbezi river in Dar es Salaam. By applying a case study approach it has been possible to make an in-depth analysis of the settlement and analyze the stormwater and flooding problems in that specific area. The collected data consists of physical and spatial mapping of the case area, supplemented by interviews and workshops. The data reveals that flooding in the settlement occurs because of excessive water run-off from upstream of the Mbezi River causing the river to overflow. The collected data has made it possible to form a clear picture of the settlement and to analyze its existing potentials and challenges in relation to limitations and future opportunities of GI and LSM. The analysis helped setting up specific design criteria for the proposal. The proposal suggests that GI and LSM systems can be implemented in the specific settlement, through removal of vulnerable houses located along the river bank and transformation of the land into a multifunctional GI and LSM system consisting of tree plantations, agricultural land and water retention systems.
