Deltares has been a heavy user of Google Earth Engine in recent years. Google Earth Engine eliminates the need to manually download and process satellite data, allowing researchers to process large amounts of satellite data faster than before. Deltares developed a new way of evaluating flood extent and permanent water by combining several remote sensing datasets in Google Earth Engine: Landsat and Shuttle Radar Topography Mission. Water maps for the last three decades anywhere in the world (with a resolution of up to 30 metres) can be produced with the new method. This ongoing research was presented at several international conferences and workshops (AGU, EGU, ESA) in 2015.
Deltares developed an algorithm, that makes it is possible to generate highly accurate water maps from satellite data without large downloads or local calculation capacity. We combined this information with knowledge about the flow of water over the terrain and OpenStreetMap GIS data. Google provides storage and through Earth Engine, its cloud-based geospatial processing platform. The results of the research were applied to generate flood maps for the Mekong River delta and to detect surface water in the Murray-Darling basin, Australia.
The water maps Deltares created are not based on single images but on time series of images. Once you have access to Google Earth Engine, the scripts and the supporting datasets, the process of creating maps is a simple matter of zooming into the area of interest using the Google interface and setting the period for analysis. The resulting maps are computed on-the-fly. Major savings in time and cost are possible.
This research received funding from the FP7 project eartH2Observe and the SERVIR Mekong project, and it is being performed in cooperation with the Delft University of Technology. The next steps will be to obtain data from other satellites to increase the accuracy of the maps and to extend the algorithm on a global level.
Thanks to our new algorithm, the availability of high-resolution satellite data, and the Google Earth Engine parallel processing platform, we can detect permanent water and determine flood extent for any place on Earth in a matter of seconds.
Deltares has been our partner in implementing regional and national projects in Asia for several years now. This unique collaboration always combines Deltares’ analytical and water modelling capability and ADPC’s disaster risk management knowledge and strong linkages with Asian governments, creating an environment that enables the countries to sustain what are produced as project outcomes long-term. We look forward to continuing this strong partnership into the future.
In this project Deltares worked together with the following partners: