Published on 18.02.2010
In the autumn of 2009, BG was commissioned to draw up a flood risk map for the portion of the Doubs River that flows through the Jura Canton.
The segment studied includes 26 km along the French/Swiss border, as well as the 31 km bend around the Clos-du-Doubs hills. The Doubs flows through a steep valley with few inhabited areas or infrastructure. The main communities potentially at risk are Goumois, Soubey, Ocourt, and the mediaeval town of St. Ursanne, which is severely affected when flooding occurs. The hundred-year flood of 1990 revealed some serious deficiencies in flood protection measures.
Because the valley is so sparsely settled, the river is still in a relatively natural state: it meanders freely and is known for its excellent fishing. However, the water balance is disrupted by the presence of hydroelectric facilities, in particular the Châtelot and Le Refrain dams upstream, which cause sudden fluctuations in downstream water levels and temperatures.
BG is responsible for evaluating flood risks and developing the risk map by fall 2010. At the same time, environmental problems will also be identified. During a second phase (early 2011), a plan for protecting and restoring the Doubs will be proposed to remedy any safety issues and environmental problems found.