Urban Development


The population of Dar es Salaam is currently estimated at 7.05 million people, with a population density of 5,061 people per square kilometer (2022 census). The city is led by the Mayor and managed by the City Council and regional government bodies.
The city’s elevation ranges from less than 5 meters above mean sea level (MSL) in the lowlands along the coast to 60-150 meters above MSL. Residential areas are predominantly made up of gently sloping terraces and hilly or flat plains, which range from 5 to 20 meters above sea level. One of the urban challenges for the city is the containment and control of flood risk in low-lying areas. The city receives over 1,000 mm of rainfall per year, with two defined rainy seasons (March to May and October to December).

DMDP has identified the following drainage challenges:

• Impact of climate change
• Inadequate stormwater drainage
• Misuse for sewage and waste disposal
• Impairment of shoreline zones

The project highlighted inadequate stormwater drainage, particularly in informal areas, due to a lack of sufficient space for retention basins. Unrestricted access to stormwater channels has been observed, leading to misuse for sewage and waste disposal.

The Dar es Salaam Metropolitan Development Project (DMDP) aimed to improve connectivity and mobility within the city while reducing flooding through both structural and non-structural measures.

Various methods were employed as part of the project, including flood modeling, surveys, hydraulic modeling, hydrological forecasting, and land cover analysis.The results were discussed for the implementation of the measures. Additionally, grievance committees were established at various levels to ensure the representation of the community, including marginalized groups such as people with disabilities and children. Although the direct impacts of the project on climate protection or climate change adaptation may vary, the application of different approaches strengthens the community’s resilience. The establishment of grievance committees promotes a community-oriented approach to disaster risk reduction and supports adaptation efforts to changing climate conditions.

The “Greening” Subcomponent of the Project
The “Greening” subcomponent, focused on combating flooding in Tanzania by implementing greening guidelines, flood models, and sustainable urban drainage systems (SUDS). This included identifying and mapping flood-prone areas and constructing rainwater channels and retention basins to regulate water flow. Specifically, 67 km of rainwater channels were built, and three retention basins were established upstream of rivers. These measures aimed to reduce the impacts of flooding and improve the quality of life for all residents, including vulnerable populations, by building capacities, raising public awareness, and implementing maintenance initiatives.

As part of the project, 67 km of the required 200 km of rainwater channels were constructed, with a focus on building the capacities of local government experts, managing solid waste, and initiating urban greening programs.

Additional Insights Gained Included:

• Early Warning Systems are Crucial: An effective early warning system that alerts the population in time about potential floods is essential. It allows people to evacuate promptly and take necessary measures to minimize damage and loss of life.
• Community Engagement is Essential: Actively involving local communities in the planning and implementation of flood protection projects strengthens trust, promotes sustainability, and increases the affected people’s responsibility for the project.
• Diverse Approaches are Required: Effective flood protection often requires a combination of structural measures (e.g., dams, dikes) and non-structural measures (e.g., land-use planning, flood prediction and warning systems).
• Flexibility is Essential: Flood protection projects should be designed flexibly, as changing environmental and social conditions can impact the effectiveness of the project.

The Dar es Salaam Metropolitan Development Project (DMDP) has made significant progress in controlling flooding and strengthening the resilience of Tanzania’s largest city. Through a combination of structural and non-structural measures, such as the construction of rainwater channels, community engagement, and capacity building, the project has addressed pressing challenges exacerbated by urbanization and climate change. However, further efforts are needed to tackle the remaining obstacles, including the impacts of climate change, inadequate infrastructure, and rapid urbanization.

By prioritizing early warning systems, involving the population, and long-term planning, Dar es Salaam can continue its path towards a more sustainable and resilient future.