The study contributes towards some best practices of carrying out community mapping exercise and, distribution of results freely on OSM and spatial data portal like MASDAP for further studies or decision making. Thus the study focused on preparing for mapping - what to map, how to map and how to record the data; the mapping exercise itself; downloading and digitizing of data in map production; and how to use the maps to aid in decision making.
The greatest threat to the people, property and economy of Malawi are natural hazards. According to Misomali (2014), since 1946, of all the 298 times the country has been impacted by hazards, 89% of those have been natural hazards while the remaining 11% have been human-generated events. According to MacOpiyo, records indicate that in the last 100 years, the country has experienced about 20 droughts in the last 100 years while in the last 36 years alone, the country has experienced eight major droughts, which have affected over 24 million people (MacOpiyo, 2017).
The problem that exists almost every year in Malawi is that it is hit by floods in quite a number of districts. Households, infrastructures: roads, schools, praying houses are affected much alike like cultivation fields. These disasters impact negatively on the social-economic growth of the communities involved and the country at large to some extent. For example MacOpiyo pointed out that in 2015 Malawi experienced a once-in-500-years flood which impacted more than 1.1 million people (MacOpiyo, 2017). Therefore the study aimed at collecting exposure data which was used for production of flood risk maps. These maps were in turn used in Atlas production.
Primary and secondary data was used in this study. Secondary data came from disaster profile from the Department of Disaster and Management Affairs (DoDMA) in Malawi which helped in identification of flood prone areas. Secondary data which was exposure data such as buildings, toilets, roads, bridges and schools among others was collected using handheld GPS with an accuracy of 3m. Choice of this data was based on how it impacts on the social-economic activities of the concerned communities. Java OpenStreet Map (JOSM) software was used for digitizing the collected exposure data by overlaying it with satellite imagery and creating attributes of that data. Thereafter, this was uploaded into a GIS environment for conducting symbolization and map visualization.
Various maps at different scales were produced which showed location of different areas that were affected by floods. These maps are used to inform the affected communities on areas that are prone to floods. The maps are shared on OpenStreeMap, Malawi Spatial Data Portal (MASDAP) and at regional and district level through workshops. Thus communities should know where to settle or not as well as where they can carry out their socio-economic activities and not be affected by flood. This also helps in building resilience among communities.
The study has shown that there is little interventions on the ground to help in reducing the root cause of floods in most parts of the country. There are a lot of mixed reasons as to the causes of floods that affect people in these areas. Living in low lying areas is the main attributed that was found for communities to be heavily affected by floods. Another reason is the siltation within rivers which is causing the rising-up of river beds is another cause of flooding in the country. These have heavily affected the poorly constructed buildings and infrastructures found in the flood prone areas. Another problem that was observed during the course of this study is lack of knowledge and information on disaster risk management. This has resulted in communities being affected when flood disaster strikes.
As a way forward, the study proposes that the government and other stakeholder must equip communities with long term interventions in building their capacities and resilience to reduce vulnerabilities. This might be in form of building of dykes along river banks that floods; enforcement of proper construction standards when putting up infrastructures and that communities must also strive to build permanent dwelling houses with strong foundations.