Ermanno Olmi, the famous Italian director, was still young when he made “Un metro lungo cinque” (roughly translated from the Italian as “One Metre Is As Long As Five”), the documentary film about the construction of the dam in Val di Lei, or the Valley of Lei.
What drew the director’s gaze and curiosity was the uniqueness of this public work, built in the 1950s by Girola and Lodigiani (two companies that were predecessors of the Salini Impregilo Group). It rises out of a natural habitat that is difficult, where the mountains had first made it unreachable by any vehicle.
Before construction of the dam began, the valley was accessible only by foot. So two cable cars were erected to facilitate the establishment of a work site. One was used to bring people, the other materials. On the north side, a road and access tunnel were built. A village was set up to host 1,500 workers. When everything was ready, work began in 1957. Four years or 1.08 million working days were needed to complete the project. The reservoir was filled by 1962.
The result turned out to be a masterpiece of engineering given the difficulties that were overcome to achieve it. The reservoir came to hold 197 million cubic metres of water. The arch dam, fifth biggest in Switzerland in terms of reservoir, is 141 metres high with a crest width of 690 metres.
The history of the dam is unique because it began on Italian soil and ended in Switzerland, the result of an exchange of land between the two countries. The reservoir lies almost entirely in Italy while the dam itself resides in Switzerland.
The construction of the dam and the filling of the reservoir that would create a large artificial lake did not discourage tourism, which had always flourished in Val di Lei. Located in the comune of Piuro in the province of Sondrio, the valley is more than 2,000 metres above sea level and it stretches for 15 kilometres. It is the only Italian alpine valley that belongs to the basin of the Rhine River, which is partly fed by the waters of the artificial lake. Winter skiers and summer campers are habitual visitors of this beautiful part of the Alps, which has remained untouched notwithstanding this huge piece of infrastructure. To this day, the valley can only be reached by road from Switzerland, which passes the comune of Ferrera. From Italy, Val di Lei is still reachable only by foot, taking the Angeloga or other minor passes that connect the valley to Spluga Valley.
At the top of the dam there is a parking lot for campers and daytime visitors. For those interested in the dam’s history, there is a centre with photographs, objects from the work site and other material. The beauty of the artificial lake is its mirror surface and the transparent water that seems like a blue tongue running along the valley. Its wealth of trout makes it an ideal spot for fishing amateurs.
During fishing season, which lasts from June to September, the lake’s shores are populated by dogs and fishing rods in search of trout.
The fascinating, unblemished mountain with its clean air, silence and incompassing peace contribute to integrating the dam with nature’s beauty.