The Mattmark Dam is the largest earthen dam in Europe and was built between 1960 and 1965. It is used for energy production, and the lake has a volume of 100 million m3.
The inauguration ceremony was followed in 1969 by Bishop Nestor Adam. On 30 August 1965, a large part of the Allalin Glacier collapsed, burying eighty-eight construction workers in the barracks under 500,000 m3 of ice. It took many months to recover their bodies. No other reservoir in Switzerland suffered a greater number of deaths during construction.
Power is produced in Zer Meiggeru and Stalden and can cover the energy needs of all households in the Canton of Valais.
Nice to know: The Mattmark Hotel and the Distelalp were also found on the plain at that time, swallowed up by the masses of water. The Hotel Mattmark was built and run by the priest Johann Josef Imseng, who was the pioneer in tourism in the Saas Valley and was also known as mountain guide and Switzerland's first skier. One day he was inexplicably found dead in the natural Mattmark lake and since then he has been celebrated as the father of tourism in the Saas Valley.