The Flood theme provides information about current and forecasted flooding in Flanders. The information shown on the map varies according to the sub-theme.
Forecasts are made on the basis of computer models. These simulate the physical properties of a waterway and compute how the water will flow through the bed. Precipitation forecasts are used as basis for these calculations.
The (HIC) officers on-duty and (VMM) operators interpret the results of these models in order to filter out the most relevant information. This interpretation can be found in the waterinfo messages.
When you click the symbols in the map, graphs appear. These can be maximised to access more details. At the top right of the map, through the icon, you can see which map layers are available. The icon provides more information about these layers. At the bottom of the map, using the icon, you can expand the legend. It explains which symbols are used in the map. You can use the search bar at the top of the map to search for an address, watercourse of gauging station in the map.
There is a glossary with frequently used terms, which is accessible through the website's footer.
The current situation tab contains measurements of water levels and flow. Gauging stations have predefined tresholds, which allow the symbols to change colour, depending on the measured water level. An overview of the gauging stations is provided under current status gauging stations. An overview of retention basins on non navigable watercourses is available under current status retention basins.
Short time forecasts
The short time forecasts have a time horizon of 48 hours. The symbols on the map change colour according to the severity of the forecast. When you zoom in on the map, flood contours and freeboards (i.e. the coloured dikes of navigable waterways) are displayed.
In the graphs, forecasts are shown as dotted lines. Some graphs contain a band of forecasts, facturing in the probability of the forecasts.
Long term forecasts
Long-term forecasts are calculated up to 10 days ahead for a selection of locations. These graphs, too, show a band of forecasts that indicate the probability of the forecast. Uncertainty bands are calculated on the basis of various possible rainfall forecasts that predict more or less rainfall. The wider the band, i.e. the further the forecasts are from each other, the greater the uncertainty.