Drought project on Doubs River shows early promise in Haut-Doubs

An experimental project on a 3.5-kilometer stretch of the Doubs River between Arçon and Doubs, near Pontarlier, aims to limit water losses during low-flow periods. With 98% of the work completed since 2025, initial on-site observations suggest cautious optimism, though multi-year flow measurements are still needed to confirm effectiveness. Drought alerts began early this year, and the river again shows dry sections in summer, particularly after Maisons-du-Bois-Lièvremont toward Morteau. This recurring phenomenon, seen in 1976, 2018, and 2022, stems partly from natural karst geology, but a 2018-2020 study on a 23-kilometer stretch found riverbed deepening and a lack of alluvial materials causing continuity breaks during prolonged heat. The project addresses these structural issues to mitigate the impacts of seasonal drought. Full results will require extended monitoring to verify whether the interventions successfully reduce water loss over time.