Bonn. Persistent rain has caused the level of the Rhine to rise, but it is expected to go down as precipitation decreases. Whether the massive amounts of snow in the Alps will have an impact remains to be seen.
The last few days and weeks of heavy rainfall have seen to it that the water level of the Rhine in Bonn rose to 5.24 meters on Wednesday. According to the prediction of the Flood Reporting Service in Mainz, which is also responsible for Bonn and the region, that is a peak level for the time being.
What are the current water levels?
Since then - as of Thursday morning - the level has dropped to just about five meters. And the trend for the coming days shows a continued decline. According to Margret Jost of the Flood Reporting Service, the reason for the level going down is the significant decline in precipitation on the Upper and Middle Rhine and its most important tributaries, the Main and Moselle. The Moselle River had a level of 3.90 meters at Thursday noon, which is a normal level for this season. For the coming days, there is hardly any precipitation predicted, so the Rhine level is expected to further decline, says Jost. On Monday, the Sieg River reached its highest level at approximately 2.99 meters in Eitorf. This week it has fallen steadily and currently stands at 1.50 meters.
Does the Sieg River play a role in whether or not the Rhine experiences flooding?
For Bonn, the Sieg River has scant influence as it only flows into the Rhine just above the city limits. But even in the region north of Bonn, the Sieg has only a minor influence, says Jost, unlike the Moselle and the Main rivers.
What are the consequences of all the snow in the Alps?
What effects the large masses of snow in the Alps could have on the Rhine level in Bonn depends on whether the snow on the upper reaches of the Rhine melts slowly or quickly. Another factor will be whether it rains parallel to that and how much precipitation is taken in by the rivers. "A rapid melting off of the snow and additional precipitation on the Upper and Middle Rhine quickly cause water levels to rise. If there is no rain, the danger of flooding in Bonn is rather low, despite all the snow", Margret Jost explains.
When are flood warnings issued?
Flood warnings for Bonn and the region are issued when a critical level has been exceeded at the reporting station in Koblenz.
(Orig. text: Dierk Himstedt, Translation: Carol Kloeppel)