Ulà Tirso, Santa Chiara Dam

The Santa Chiara dam is a majestic artificial barrier (270 meters long and 70 meters high), now abandoned. It is located in the territory of Ula Tirso; the latter town is located in the historic region of Barigadu. The work for the construction of this hydraulic engineering project began in 1918, when, after the Great War, solutions were being sought to the age-old problem of drought, to the problems related to the presence of unhealthy malarial soils and the growing need for electricity in a territory plagued by poverty.
The design was entrusted to the engineer Angelo Omodeo, after whom the artificial lake originated from the construction of the dam took its name. Instead, the engineer Giulio Dolcetta, a figure linked to the island's great land remediation works, directed the works. The inauguration of the large straight building, with multiple arches, resting almost completely on a compact trachyte counter, was held on April 28, 1924 in the presence of the King of Italy, Vittorio Emanuele III.
Simultaneously with the work aimed at building the great barrier, the small village of Zuri, which was 88 meters above sea level and which would have been irretrievably submerged by lake water, was demolished. The town was rebuilt upstream, together with the church of San Pietro di Zuri, one of the most important monuments of medieval island architecture, which, when disassembled, was faithfully rebuilt one after another. The church in question owes its importance to the presence of an inscription that, in addition to tracing its construction back with certainty to 1291, identifies the identity both of the client (in the person of the abbess Sardigna de Lacon, probably linked by relationships of affinity to the House of the Judikes of Arborea) and of the architect in the master Anselmo da Como. Among the figures in relief on the portal, in addition to Saint Peter with the keys, there is a figure in monastic dress, prostrated, probably identifiable with the abbess Sardigna de Lacon.
The religious building also stands out for an interesting decorative relief motif, which is located in the capital between the right side and the wall of the apse, interpreted by many as the oldest representation of Sardinian dance.
The waters of Lake Omodeo hide treasures: a fossil forest dating back 20 million years ago and important archaeological emergencies, such as a prenuragic settlement, domus de janas and giants' tombs.
The construction of the Santa Chiara dam involved 16,000 workers (many of them women). Of them, 56 died during the performance of the opera, including Antonio Gramsci's 31-year-old sister, Emma.
Around the end of the '60s, on the occasion of one of the periodic checks to which the structure underwent, the presence of significant injuries was found at some critical points of the barrier, in particular near the buttresses. This state of affairs entailed the search for new solutions that would be able to meet the increasingly growing demand for water resources capable of satisfying both agricultural and industrial needs, especially in view of the construction of the Ottana industrial hub.
On January 23, 1997, a new dam was inaugurated, named after the judge Eleonora d'Arborea, which completely replaced that of Santa Chiara. After more than 70 years of operation, the Santa Chiara dam was abandoned and currently lies semi-submerged in the artificial lake that it had created.