As a flood control specialist writing for Flood Control 2015, I’ve witnessed firsthand the devastating impacts of floods on vulnerable urban communities, particularly in the rapidly growing cities of the developing world. One such example is Dar es Salaam, Tanzania, where rapid urbanization and unplanned growth have left many of its residents living in informal settlements highly susceptible to the devastating effects of flooding.
Now, this might seem counterintuitive…
Flood Risk and Vulnerability
Dar es Salaam, a commercial port city on the Indian Ocean, is considered one of the fastest-growing cities globally, with a projected population of 10.79 million by 2030. However, the city’s geography and infrastructure challenges have made it increasingly prone to severe flood events. The Msimbazi River running through the city, combined with its low-lying coastal orientation, creates ideal conditions for flooding, which have been exacerbated by rapid urbanization – 70% of the city’s inhabitants reside in informal settlements.
Flood Hazard Assessment
Issues such as clogged drainage channels due to inadequate solid waste management, a lack of natural drainage outlets, unplanned housing construction, poor sanitation infrastructure, and limited municipal capacity to issue flood warnings and evacuate communities all contribute to the heightened flood risk facing Dar es Salaam’s most marginalized residents. Climate change is only further exacerbating these challenges, with extreme rainfall events becoming more frequent and intense.
Exposure and Vulnerability Analysis
In April 2014, three consecutive days of torrential rainfall caused extensive flooding across the city, resulting in 19 fatalities and displacing 20,000 people from their homes. The impact of these floods disproportionately affected the urban poor, damaging critical infrastructure and disrupting livelihoods. This highlights the fundamental socio-environmental inequalities present in the city, where flood-induced losses to human and economic capital have slowed the city’s overall development and reduced opportunities for the most marginalized residents to escape poverty.
Flood Modeling and Mapping
Addressing these challenges has become a pivotal area of development for Dar es Salaam, as the city seeks to embed environmental resilience into its vulnerable neighborhoods and enhance the urban quality of life for local communities. However, a key barrier has been the lack of high-quality, up-to-date mapping data – a crucial tool for informed decision-making and flood prevention in the city.
Community-Based Flood Resilience
In response to this issue, the Dar Ramani Huria (open mapping) project was launched in 2015, with support from the World Bank and funding from the UK’s Department for International Development. This innovative, community-driven initiative aimed to mobilize local residents to collectively map the city’s flood-prone neighborhoods, minimize the impact of floods in high-risk areas, and enhance community-level understanding and preparedness for natural disasters.
Participatory Mapping and Risk Assessment
The project was led by the Humanitarian OpenStreetMap Team (HOT) and OpenMap Tanzania, in partnership with the Tanzanian Red Cross and a wide range of stakeholders, including universities, government agencies, and international organizations. The initial phase of the project, launched in 2015, focused on training students from Ardhi and Dar es Salaam Universities to work with local community members to map the city’s critical infrastructure, drainage systems, and other key features using paper-based data collection and GPS technology.
Capacity Building and Training Programs
This data was then uploaded to the collaborative OpenStreetMap (OSM) platform, enabling the creation of highly detailed flood maps to inform urban disaster risk decision-making and mitigation strategies. The project also facilitated the development of disaster preparedness and response plans for the city’s most flood-prone wards, working closely with trained Community Disaster Preparedness and Response Teams.
Emergency Preparedness and Response
The success of the initial phase of Dar Ramani Huria led to the launch of an enhanced version, Dar Ramani Huria 2.0, in 2017. This new iteration integrated smartphone-based data collection using open-source tools like OpenDataKit (ODK) and OpenMapKit (OMK), enabling more systematic data collection, real-time monitoring, and improved data quality assurance. The project also expanded its scope to include detailed mapping of drainage networks, soil analysis, and the development of flood forecasting models – all of which helped to further inform municipal disaster planning and community-level preparedness.
Climate Change Adaptation
As Dar es Salaam continues to grapple with the impacts of climate change, the Dar Ramani Huria project has played a crucial role in enhancing the city’s adaptive capacity and resilience. By involving local communities in the mapping and data collection process, the project has not only generated high-quality, actionable information but also built the technical skills and awareness of residents, empowering them to take an active role in addressing flood-related challenges.
Scenario-Based Risk Projections
The flood maps and risk data produced through the project have enabled municipal authorities and urban planners to better understand the city’s vulnerability to climate-related hazards, informing the development of more targeted and effective flood mitigation strategies. Additionally, the integration of these maps with software like InaSAFE has allowed for the creation of realistic flood scenario models, supporting more robust disaster planning and response efforts.
Nature-Based Solutions
Looking ahead, the Dar Ramani Huria project has also explored the use of innovative, nature-based solutions to enhance the city’s flood resilience. This has included the deployment of drones for remote monitoring of infrastructure and river basins, as well as the incorporation of green infrastructure elements, such as improved drainage and retention systems, to complement traditional flood control measures.
Policy and Governance
The success of the Dar Ramani Huria project has highlighted the critical importance of fostering strong partnerships and collaborative governance structures to address complex urban challenges like flooding. By bringing together a diverse range of stakeholders, including government agencies, community organizations, academic institutions, and international development partners, the project was able to leverage a wealth of expertise and resources to jointly develop and implement flood resilience strategies.
Flood Risk Management Frameworks
One of the key achievements of the project was the establishment of the Dar es Salaam Urban Forum, a quarterly meeting that enhanced coordination between relevant actors and bolstered long-term resilience planning for the city. This collaborative approach not only helped to double-check that equitable resource allocation but also enabled the integration of community-generated data and knowledge into the city’s disaster risk reduction and management frameworks.
Financing Mechanisms for Flood Mitigation
Securing adequate and sustainable financing for flood control and resilience-building initiatives remains a significant challenge for many cities in the developing world. The Dar Ramani Huria project has demonstrated the potential for leveraging international development funding, such as support from the World Bank and Red Cross Movement, to catalyze community-driven solutions and build local capacities. As urban practitioners, we might want to continue to explore innovative financing mechanisms, including public-private partnerships and climate adaptation funds, to double-check that the long-term viability and scalability of such initiatives.
Lessons Learned and the Way Forward
The case of Dar es Salaam has underscored the intrinsic vulnerability that marginalized urban communities face in the context of natural disaster risk, particularly in relation to flooding. A combination of poor infrastructure, reduced adaptive capacity, and geographic susceptibility to flood events in the city’s informal settlements have reinforced the importance of targeting high-risk neighborhoods within broader resilience strategies.
In line with the Sustainable Development Goals’ principles of leaving no one behind, cities and municipal governments might want to prioritize socio-environmental justice as a core component of sustainable urbanization efforts. Community-driven initiatives, such as the Dar Ramani Huria project, have demonstrated the power of participatory mapping and data-driven decision-making to enhance the flood resilience of vulnerable urban communities.
As flood control specialists, we might want to continue to advocate for and support the adoption of such community-centric approaches, which not only generate high-quality, actionable data but also build the technical capacities and self-organization of local residents. By empowering marginalized communities to actively engage in the flood risk assessment and mitigation process, we can foster more equitable, resilient, and sustainable cities that are prepared to withstand the increasingly severe impacts of climate change.
To learn more about innovative flood control solutions and community-driven resilience initiatives, I encourage you to visit https://www.floodcontrol2015.com/.
Tip: Regularly inspect and maintain flood barriers and drainage systems
