Bruna dam
The Bruna dam (Italian: Diga dei Muracci ) was built in the 15th century in the Republic of Siena in what is now Italy on the Bruna River .
Location and type of construction
It stood northeast of the municipality of Gavorrano on the border with Roccastrada , north of Giuncarico (Gavorrano) and southwest of Ribolla (Roccastrada) in the Brunatal, where it opens to the Maremma plain. The reservoir , called Lago di Pietra (also called Lago della Bruna ), was supposed to be used to breed fish. The name for the Lago di Pietra was given by the nearby fortress and today's ruins Castello di Pietra (also called Castel Pietra).
According to the documents that have been received, the wall was a gravity dam type , up to 18 m high, 12 m at the base and 6 m wide and 300 m long at the top of the wall. Planning began in 1468 and construction in 1470. 22 years later, the dam collapsed in December 1492, with an unknown number of deaths.
history
The first plan by Pietro dell'Abbaco, a mathematician, was that around 17,500 cubic meters of stone and building materials would be needed. The master builders were Matteo di Iacopo (Matteo Jacopo di Muriano) and Adamo di Domenico (Adamo di maestro Domenico di San Vico in Val di Lugano, † 1473). In 1471, the year after construction began, it was realized that the construction had to be changed because it would not have been sustainable. Seven pillars were added in the middle of the wall . In 1473 it was found that the amount of building material needed had doubled to 35,000 cubic meters. The valley must have been cordoned off in 1475, but the first damage occurred. The overflowing water created a hole on the air side of the wall.
From 1481 there is a petition for more money, with which another 16,000 cubic meters of stone should be built. Repair work appears to have progressed more slowly after 1481. In 1492 the structure must have been almost finished, but it was obviously not in good condition. In 1492 the Sienese asked the Duke of Calabria to send back the builder Francesco di Giorgio Martini , who had left the year before. But he didn't come back until December. According to a last call for help on December 4, 1492, which has been received in writing, the dam was in great danger and threatened to break, which it did in the last days of December. A great flood developed in which people and animals died.
There were several plans to rebuild the dam. Parts of the plans, including those by Baldassare Peruzzi , have survived to this day, but were never implemented. The flooding of 1532 also destroyed large parts of the remaining facilities. Today three larger fragments of the wall can still be seen, especially the end pieces on the sides. In addition to the two remains on the slopes, there is also an arch-shaped remnant on the waterside (northwestern) side of the dam. The center piece has not been preserved.
See also
literature
- Nicholas Adams: Architecture for Fish: The Sienese Dam on the Bruna River-Structures and Designs, 1468 – ca. 1530 , in: Technology and Culture, Vol. 25, No. 4 (Oct. 1984), pp. 768-797
- Roberto Farinelli / Riccardo Francovich : La diga rinascimentale sul fiume Bruna , in: Guida alla Maremma medievale. Itinerari di archeologia nella provincia di Grosseto, pp. 75–84, Nuova Immagine Editrice, Siena 2000, ISBN 978-88-7145-170-1 , online edition (PDF file; 1.14 MB) of the University of Siena
- Emanuele Repetti: Dizionario Geografico Fisico Storico della Toscana , online edition of the University of Siena on Lago di Pietra (Lago della Bruna) and the dam
Web links
Individual evidence
- ↑ cf. Repetti
- ↑ Website of Castelli toscani Castel Pietra, called 2012 (Ital.) On April 7
- ↑ cf. Farinelli / Francovich