sticks under the bridge.

 On the final part of the day's walk, the long part along by the river, notice that all the underpasses for pedestrians have been closed. Apparently the danger of imminent flooding is getting worse, the river has changed from its usual placid flow to a raging brown torrent. It is a brown much like milky tea, and there are bits of stick and larger bits of driftwood floating there. 

Cross the river using the big bridge, and then keep walking upstream. This is the area known as the mill island, or the Mühleninsel. There is still large flour mill there. The bridge over the flood gates by the power plant has been closed, there are many logs and other bits of flotsam jammed against the gates. The river is roaring over the lowered steel barriers, thousands of cubic metres every minute. There is spray and foam everywhere. Later on men with heavy plant will remove the branches jaammed against the piers of the flood gates.

At the next bridge there is a crowd of tourists watching the approach of a particularly large log, some are using their mobile phones to capture videos of the whole affair. The log passes under the bridgle, all the watchers run over to the other side to pursue the log on it's further course downriver with their eyes.

It is just like that story with the bear and the piglet.