© Céline Spithoven/RTL
Water levels at Luxembourg's Upper Sûre Lake have dropped to their lowest point since 2011, forcing the early halt of the popular solar boat tours, though drinking water supplies remain secure and tourism largely unaffected.
The Upper Sûre Lake, one of Luxembourg's favourite summer destinations, is currently around two to three metres lower than usual, marking its lowest level since 2011.
The unusually low water level has had a direct impact on the solar-powered boat operated by the Upper Sûre Nature Park, which normally runs educational tours until autumn but stopped operating already on 1 September.
Jeff Gangler, President of the Nature Park, explained that the decision was made purely for safety reasons. With the current water level, the pontoon leading to the boat had become too steep, at a slope of around 40 per cent, making access unsafe, he explained.
Gangler added that given the risks, they decided to suspend operations, stressing that the activity begins well above the lake where lifejackets and information are distributed, so safe boarding could no longer be guaranteed.
Drop is linked to winter construction works
The Upper Sûre Lake is allowed to fill up to 320 metres above sea level in summer and 317 in winter, but it currently stands at just 313.6 metres.
Roland Fox, Director of the National Roads Administration, explained that the drop is linked to winter construction works on the banks near Insenborn.
To prevent the embankment from collapsing, water had to be released to allow work to proceed, he explained. He noted that once the work was finished, they waited for the rainfall to restore normal levels, but due to lack of rainfall, the lake is about two metres lower than in a normal year.
Drinking water supply remains secure
At the same time, work is under way on a new automatic spillway system, which will replace the current manual discharge of excess water from the dam.
André Weidenhaupt, President of the water syndicate SEBES, pointed out that once operational, this system would stabilise winter levels and avoid similar situations in future. He explained that in winter, it would no longer be necessary to release water, such that water level could be kept more constant.
Despite the visibly lower levels, Luxembourg's drinking water supply remains secure. The reservoir still holds over 30 million cubic metres of water, while SEBES requires only around 1.5 to 1.8 million cubic metres per month.
The bigger concern, Weidenhaupt explained, is quality: warmer water can encourage bacterial growth, so treatment requires closer monitoring. However, he stressed that with the new Esch-sur-Sûre treatment facility, the issue is under control.
Nature Park remains a tourist magnet
For the Nature Park, the early halt of the solar boat is regrettable, particularly because it plays a valuable educational role for school classes and groups. Still, Gangler emphasised that the overall tourism offer remains strong, with plenty of hikes and activities that continue to attract visitors. He noted that even if the weather is not always perfect, they still have much to offer.
