The Lac des Brenets, a scenic lake situated on the border between France and Switzerland, has dried up following an exceptionally hot summer, provoking concern and calls for urgent intervention from local residents and business owners. The lake, formed by the Doubs river at the village of Les Brenets—located between France’s Franche-Comté region and Switzerland’s Neuchâtel canton—has long been a site for recreation and tourism, but this year it has all but vanished.

Local historian David Favre, 76, described the situation as “emotionally devastating,” recalling childhood summers spent swimming, diving, and fishing at the lake. He said the lake has been increasingly vulnerable since a drought in 2018, with water levels declining more frequently, sometimes even suggesting it may soon dry out annually. Favre expressed frustration, accusing authorities of abandoning efforts to preserve the lake.

Several factors have contributed to the lake’s decline, including persistent heatwaves, below-average rainfall, and geological fissures beneath the lakebed that drain water underground. The summer months of June, July, and August each recorded the highest temperatures ever measured in Switzerland since 1864, exacerbating the drought conditions.

The lack of water has also stopped the 27-meter-high waterfall at the lake’s outlet, once a defining feature of the landscape. Yvan Durig, owner and captain of the Lac des Brenets navigation company, reported that where there used to be 25 to 30 meters of water depth, only about nine meters remain. He noted the overcrowding of fish in the shrinking basin as a negative ecological sign. Durig expressed particular concern over the impact on tourism and local livelihood, explaining that boat operations were halted on July 20 due to the falling water levels, a blow to his business that normally transports 200 to 300 passengers daily during the season.

Efforts to address the decline have included the formation of a Franco-Swiss task force in 2022 aimed at limiting water loss through the fissures. However, critics argue these initiatives have yet to produce tangible results. Durig and others warn that time is running short and urge proactive measures, such as sealing the lakebed to prevent further drainage. The water level continues to drop rapidly—by approximately 20 to 22 centimeters daily—and is expected to soon surpass the historical low recorded in 1906.

Residents and workers connected to the lake describe a sense of loss and concern for the future, with some fearing that Lac des Brenets could disappear entirely without immediate and sustained action. The lake, long considered part of the “soul” of Les Brenets, now stands as a symbol of environmental vulnerability in the face of climate change and shifting weather patterns.