From Field Data to Impact: Understanding the Ramani Zetu, Sauti Zetu Data Workflow
By Aisha Hamisi and Asha Mustapher
On February 16, 2026, OpenMap Development Tanzania began implementing the Zayed Sustainability Prize’s funded project Ramani Zetu, Sauti Zetu in 20 wards of Dar es Salaam, focusing on assets and threat mapping, flood extents mapping, and drainage mapping in the Ubungo, Ilala, Kinondoni, and Temeke municipalities. By combining participatory mapping with field data collection, the project aims to collect data from the community for disaster risk preparedness, urban planning, and climate resilience.
Before starting field data collection, it was essential to build the mappers’ capacity. A total of over 42 mappers were equipped with practical knowledge and skills in mobile data collection using ODK, participatory mapping methodologies, and the proper use of field equipment such as measuring rods and measuring tapes. The three-day training, conducted at the University of Dar es Salaam, was intentionally designed to prioritize hands-on application over theory. Participants engaged directly with the data collection tools, conducted mock interviews, practiced form-filling, and participated in field exercises to ensure readiness for real-world data collection.
What makes this phase particularly unique is that 60 percent of the mappers are new youth participants whom we have not previously worked with. Nevertheless, they have never used mapping tools before. This inclusion of new faces expands local technical capacity and builds a new generation of young practitioners skilled in geospatial data collection and climate resilience mapping.
During the training, these 42 mappers were divided into 2 teams: the first handled drainage mapping, and the second handled assets and threat mapping, and the floods extent mapping.
Drainage Mapping Team
The drainage mapping team consists of 19 members, collects data across 18 wards in Dar es Salaam, and has received comprehensive technical training to ensure systematic, high-quality data collection. During the training, mappers developed a clear understanding of urban flood risk dynamics, drainage infrastructure typologies, infrastructure condition assessment methodologies, and standardized data quality control procedures. They were trained to accurately map drains, culverts, ditches, and channels, assess their structural condition and functionality, and capture precise geospatial data using digital tools. Now moving into the field, the team is applying these competencies using Open Data Kit (ODK), measuring rods, and structured survey tools to collect consistent and verifiable drainage data. This effort aims to map infrastructure in previously unmapped wards while upgrading existing datasets in already mapped areas.
Assets and threat mapping team
The Asset and Threat Mapping team, composed of 23 trained mappers, is responsible for collecting data across 13 wards to support climate resilience and disaster preparedness in vulnerable communities. Following targeted training, the team has been equipped with technical and facilitation skills in participatory mapping, spatial data documentation, and mobile data collection using ODK Collect.
During implementation, the team works closely with communities through participatory mapping workshops, where residents identify and document critical assets and potential threats directly onto base maps. Using a standardized color-coding system, community members classify key features such as assets at risk, safe assets, and hazard zones. This approach ensures that local knowledge is effectively captured and translated into structured spatial data.
The information generated through these sessions is then validated through field verification and digital data collection to ensure accuracy, consistency, and credibility. The resulting datasets provide essential insights for disaster preparedness planning, risk reduction, and informed decision-making at the local level.
Flood Extents Mapping Team
The Flood Extent Mapping team focuses on identifying and documenting flood-prone areas across the same 13 wards by combining community knowledge with evidence-based field data collection. Trained in flood risk identification and spatial validation techniques, the team works with residents to map historical flood boundaries, water levels, and duration of flooding events.
Through participatory engagement, community members indicate how far floodwaters typically extend, which areas are most affected, and how flood patterns have changed over time. This qualitative information is then systematically collected through field mapping and recorded using ODK Collect to ensure spatial accuracy.
The integration of community insights with geospatial data enables the production of reliable flood extent maps that support disaster preparedness, response planning, and urban development processes.
Data Validation, Cleaning, and Visualization
After field data collection, a few mappers (4) with data quality assurance experience were assigned to handle daily data cleaning. These QA officers were trained to use advanced data-cleaning tools, including QGIS and Excel, under the guidance of the GIS and data manager. For the final cleansing of data, Python and R were used to clear all the data ambiguities and inconsistencies.
To strengthen their capacity, the same team participated in the full data collection process, including training and pilot exercises. This helped them understand how data was collected, the challenges faced in the field, and how communities interpreted questions. As a result, they gained a clear understanding of the data structure, patterns, and the meaning of symbols and colors used during mapping.
The team cleaned all the data collected each day. This allowed them to identify errors early and inform field teams to correct issues before moving to the next ward.
Next, after data cleaning, the team was divided into 8 teams to conduct data validation. Each team of three (3) revisited mapped sub-wards and worked with local leaders to verify the accuracy of the data using printed maps. When errors were identified, teams returned to the field to collect the correct information.
Once validation is complete, the data will be visualized and used to produce final maps. These maps will show flood-prone areas, community assets at risk, evacuation routes, safe locations and evacuation points, and drainage patterns and conditions.
What next
The next step is to use the data to develop community flood preparedness plans and a community-based early warning system. These plans will guide actions for communities and Ward Disaster Management Committees to prepare for and respond to flooding in selected wards.
The data will also be used to identify locations for awareness campaigns targeting primary schools and communities, plan clean-up activities in high-risk areas, especially blocked drains and rivers, and support targeted interventions to improve drainage and water flow in 10 selected wards.
In addition, the team will identify critical locations that require small-scale infrastructure improvements. These may include clearing drainage channels and improving water pathways to reduce flood impact. This approach, referred to as supportive infrastructure upgrades, will rely on mapped data and community input to ensure actions respond to real needs.
