For the Doubs, this is well-known that it is losing water under its bed and that the Loue river is this water coming out at a different point. You can see the

For the Doubs, this is well-known that it is losing water under its bed and that the Loue river is this water coming out at a different point. You can see the source of the Loue[0] on the Wikipedia page. The river is basically coming out of the mountain with already a very high flow rate. This is one of the nicest river in the east part of France, it is a pleasure to walk along or navigate it. Edit: Found videos[1] where you can see the holes sucking the water in the river bed. [0]: https://en.wikipedia.org/wiki/Loue https://en.wikipedia.org/wiki/Loue [1]: https://www.estrepublicain.fr/edition-haut-doubs/2018/07/31/doubs-a-sec-entre-pontarlier-et-morteau-les-failles-responsables https://www.estrepublicain.fr/edition-haut-doubs/2018/07/31/...