Currently 1.8 million people live in areas at risk of flooding across the UK. With an increasing population and dependence on flood plains for housing and industry, loss of natural flood defences and increased likelihood of extreme weather events; this figure is projected to rise. When a flooding event occurs, the level of disruption is determined by the level of prior preparation, and the speed information can be gathered and analysed and appropriate responses put in place.
I manage the Geomatics team at the Environment Agency; we use remote sensing to produce leading edge earth observation solutions. For example during an Incident we provide information on the flood extent, pollution risks and infrastructure damage. To carry out these observations, the Environment Agency has a suite of different tools available best suited to different situations.
During the winter 2015/16 flooding across Cumbria and Yorkshire, we assessed flooding extent using traditional methods of aerial photography taken from aircraft. This method allows extensive information to be captured quickly, with data across the entire area collected within one day.
To get a broader overview, satellite data is used. After a request for information on the extent of flooded farmland, within 36 hours the team downloaded the appropriate data, ran analysis for presence or absence of water and determined the extent of the flooding. Earth Observations were able to provide a free, efficient and low carbon method for determining flood extent in a relatively short space of time.
To assess smaller scale flooding incidents in higher detail, drone technologies have proved useful. We responded to an information request to assess an inaccessible river breach. A drone was sourced and supplied to provide an up close and detailed live stream, allowing quick and efficient assessments and plans to be made.
In an emergency, rapid evidence collection is critical for appropriate actions to be made. To do this, the Environment Agency needs to make sure they have the correct tools for the job. Satellite data gives a broad overview of flooding extent, aerial photography is appropriate if the flooding is discrete but widespread, and if more detailed observations are required a drone may be the best platform.
Although we cannot stop floods from occurring, we can make sure that by using the most up to date technologies available, the Environment Agency is armed with all the information as fast and as cost effectively as possible. With increasing flood risk, our work on harnessing these new innovations will become ever more important.
This blog was reposted here with permission and first appeared on the Defra digital blog here: https://defradigital.blog.gov.uk/2017/03/30/up-up-and-very-far-away-remote-sensing-in-flood-response/