Lai da Sontga Maria, reservoir in Grisons, Switzerland

Lai da Sontga Maria is a reservoir north of the Lukmanier Pass, lying almost entirely in Medel, Grisons, with a small southwest part in Quinto and Blenio, Ticino. Its 117 m arch dam, completed in 1968, stands at the northern end; the pass road runs along the eastern shore. The lake lies at 1,908 m, overlooked by the Scopi (3,190 m) to the east and Pizzo dell'Uomo (2,663 m) to the south.

The lake was created in 1968 by an arch dam on the northern side to store water for hydroelectric power generation. This construction transformed what was once grazing and farming land into a modern water storage facility that has served the region for decades.

The Romansh name means Lake of Saint Mary, referring to the chapel of Sontga Maria that gave the Lukmanier Pass its name. The pass road runs along the eastern shore, and the dam crest carries a radio mast used by Sunrise, Orange and Swisscom. The lake lies at 1,908 m, overlooked by the Scopi (3,190 m) to the east.

The lake is easily accessed from the Lukmanier Pass road, with parking areas and walking paths along the shoreline available throughout the year. Visit between late spring and early fall for the most comfortable weather and clearest mountain views.

A power transmission pylon stands directly in the water, carrying electricity across the mountains via the Lukmanier line. This unusual structure in the lake reminds visitors of how the region balances modern energy needs with the natural landscape.