In the heart of Ethiopia’s Blue Nile basin, the Gumara River catchment has long been a battleground between the life-giving waters of the river and the agricultural lands that depend on it. Each year, floods along the Gumara River destroy vast swathes of farmland, threatening the livelihoods of local communities. But a new study published in *Environmental Systems Research* offers a glimmer of hope, demonstrating how advanced satellite technology can help monitor and mitigate these devastating floods.
The research, led by Destaw Kassaw from the Department of Geography and Environmental Studies at the University of Gondar, leverages Sentinel-1 SAR satellite data to track flood extents and assess damages. “Sentinel-1 SAR data provides essential temporal resolution and backscatter values for monitoring flood damages,” Kassaw explains. This high-resolution data, combined with advanced analytical techniques, allows for precise flood hazard mapping and risk assessment.
The study utilized Sentinel-1 SAR images from July and August 2021 to analyze flood extents. By employing a histogram-based thresholding technique, the researchers identified a significant increase in flood extent from July 11th to August 4th. The August 4th flood event alone covered an area of 11.97 km², with agricultural land bearing the brunt of the damage. “Agricultural land was the most affected, with 7.48 km² inundated during the August 4th flood event,” Kassaw notes.
The researchers considered various factors such as land use/cover, slope, elevation, soil, and flood depth to create comprehensive flood hazard maps. Using the Analytical Hierarchical Process (AHP) and weighted overlay analysis, they produced detailed flood risk maps in a GIS environment. The findings revealed that 12.7% of the Gumara catchment was subjected to very high flood hazards, with 21.75% of agricultural land falling within very high flood risk zones.
The commercial impacts for the agriculture sector are substantial. By identifying high-risk areas, farmers and agricultural businesses can implement targeted mitigation strategies, such as early warning systems, land-use zoning, and embankments. “Flood monitoring and mitigation strategies should be implemented to protect Agricultural lands and support sustainable farming practices,” Kassaw emphasizes.
This research not only highlights the immediate benefits of advanced flood monitoring but also paves the way for future developments in the field. As satellite technology continues to evolve, the integration of Sentinel-1 SAR data with other remote sensing tools, such as Sentinel-2 and Digital Elevation Models (DEM), could provide even more precise and timely flood assessments. This could revolutionize flood management strategies, offering farmers and agricultural businesses the tools they need to protect their lands and ensure sustainable productivity.
In the face of climate change and increasing natural disasters, the need for innovative solutions has never been greater. This study offers a promising approach to flood monitoring and damage assessment, demonstrating the power of technology in safeguarding agricultural lands and supporting sustainable farming practices. As we look to the future, the integration of advanced satellite data and analytical techniques will be crucial in mitigating the impacts of natural hazards and ensuring food security for communities worldwide.