Sufnersee, reservoir

Sufnersee is a reservoir on the Hinterrhein between Splügen and Sufers in the Grisons, held by two structures: the 10-metre-high, 244-metre-long Crestawalddamm earth-fill dam and the 58-metre-high, 125-metre-long Sufers arch dam, both completed in 1962. It lies at 1,398 m above sea level, directly south of the A13, and Sufers is the only village on its shore.

The Sufers dam and the 244-metre Crestawald earth-fill dam were completed and put into service in 1962 by Kraftwerke Hinterrhein AG, based in Thusis, which still operates them. Water is diverted about four kilometres downstream to the Bärenburg power plant, and can also be pumped up to Lago di Lei via the Ferrera plant. Around 30 hectares of meadow and pasture were lost to the full impoundment; humus removed from the future reservoir bed was spread on poor soils outside to offset the fodder loss.

The reservoir takes its name from Sufers, the only village on its shore, and lies on the Hinterrhein between Sufers and Splügen. It was built by Kraftwerke Hinterrhein AG, based in Thusis, which still operates the dams and power plants. Water flows about four kilometres down the valley to the Bärenburg power plant, and can also be pumped up to Lago di Lei in the neighbouring Val Ferrera via the Ferrera plant.

The reservoir can be reached by a short walk from the parking area near Sufers, and it is recommended to arrive early during busy seasons to find a good spot. The trail is well-marked and easy to follow, so comfortable footwear is sufficient for the visit.

The reservoir holds 17.5 million m³ and covers 0.90 km². Its water can be pumped up to Lago di Lei in the neighbouring Val Ferrera via the Ferrera power plant, and otherwise flows down to the Bärenburg plant about four kilometres away. Around 30 hectares of meadow and pasture were lost when the lake filled; humus stripped from the future lake bed was spread on poor soils outside to offset the fodder loss.