The Need for Better Flood Monitoring in the UK
Over 5.5 million homes and businesses in England currently face the risk of flooding. This threat is projected to escalate due to climate change and ongoing development. Traditional flood mapping methods, such as aerial surveillance and ground-based surveys, are often expensive, time-consuming, and can be dangerous in emergency situations. Furthermore, the UK has historically lacked a complete and consistent record of past flood events, particularly for widespread incidents. This makes effective long-term planning and quick, informed responses incredibly difficult.
How Does SatSense FloodMap Work?
SatSense FloodMap is a semi-automated system that combines the power of Sentinel-1 Synthetic Aperture Radar (SAR) satellite data with high-resolution, UK-specific datasets like LIDAR. SAR satellites are ideal for flood monitoring because their microwave signals can penetrate clouds and operate day or night, overcoming the limitations of optical satellites that rely on clear skies and daylight. This is particularly crucial in the UK, where cloud-free conditions are infrequent, especially during flood events.
Our system employs a sophisticated probabilistic time-series approach to determine the likelihood of flooding for each pixel. This method accounts for inherent uncertainties and sources of error in SAR data, providing highly reliable classifications. Auxiliary data, including the Environment Agency's LIDAR digital surface model, further refines the outputs, ensuring greater accuracy.
Figure 1: Binary flood map over the Midlands produced for a Sentinel-1 image taken during Storm Henk on 2024-01-04. The exclusion mask removes pixels where the radar backscatter intensity is insensitive to the presence of surface water. Permanent water bodies are distinguished from flooded areas that are not covered by surface water in normal conditons.What are the Key Features of SatSense FloodMap?
SatSense FloodMap offers a robust set of features designed to provide transparent and high-frequency flood monitoring across the UK:
- High-Resolution Mapping: Operates at a 10–25 meter resolution using open-access SAR data, providing detailed flood extents.
- Daily Insights: Delivers current flood maps quickly after every satellite overpass, crucial for emergency situations.
- Comprehensive Historical Archive: Builds a valuable record of past flood events from 2015 onwards, essential for risk assessment and model validation.
- Enhanced Accuracy: Seamlessly integrates with high-resolution UK-specific LIDAR, land cover, and height datasets to improve precision.
- Flexible Data Delivery: Provides outputs as GeoTIFFs for easy integration with GIS software, with options for API and web access.
How Has FloodMap Proven Its Accuracy?
We've rigorously validated FloodMap's capabilities against real-world events. Our system has been successfully applied to recent major UK flood events, including Storm Henk in 2024, the January 2023 floods in Somerset, and the November 2019 Fishlake floods. In comparative assessments, FloodMap's outputs aligned very well with independent observations from optical satellites, demonstrating strong agreement and superior performance. This robust validation ensures that you can trust the accuracy of our flood maps for critical decision-making.
How Can You Get Started with SatSense FloodMap?
SatSense FloodMap is designed to bolster UK resilience through transparent, high-frequency monitoring. We understand the diverse needs of different organizations, from emergency services and local councils to flood consultancies and insurers. Our team is ready to help configure data delivery to meet your specific operational requirements.
Ready to see FloodMap in action? Contact us today to request a demonstration, explore historical case studies, or discuss API integration for your real-time applications.
Frequently Asked Questions (FAQ)
What types of flooding can FloodMap detect?
SatSense FloodMap is currently optimised for rural flooding events. Future developments aim to extend its capability to dense urban areas.
How quickly are flood maps available after a satellite overpass?
SatSense FloodMap can generate near real-time flood maps within hours of Sentinel-1 data acquisition, making it a valuable tool for emergency response scenarios.
Can FloodMap provide historical flood information?
Yes, FloodMap can generate comprehensive catalogues of historical flood maps over the UK, utilizing the decade-long database of Sentinel-1 observations dating back to 2015. This historical data is crucial for validating flood risk models and improving forecasting.
What is the future potential of SAR satellite flood monitoring?
By 2030, further launches of open-access SAR satellites, such as NISAR, Sentinel-1D, and ROSE-L, are expected to provide sub-daily observations over the UK, significantly enhancing the potential for near real-time flood monitoring. This increased data frequency will greatly improve our ability to track and respond to flood events.
Author: SatSense Team