Muro da Prega
|Muro da Prega
also: Barrage de Pisões
|Data on the building|
|Height of the barrier structure:||Approx. 5 m|
|Crown length:||62 m|
|Base Width:||6 m|
|Data on the reservoir|
|Water surface||Approx. 8500 m²dep1|
|Dam length||Approx. 130 mdep1|
|Storage room||Approx. 6200 m³|
The Roman dam Muro da Prega – also Barrage de Pisões – lies in the middle of fields, about seven kilometres west of Beja in Portugal. Green vegetation indicates the course of the stream that today flows past the dam, which has been destroyed on one side.
The dam wall, which is over 6.0 m thick, consists of individual wall courses built close together in layers. The almost straight wall, built of green masonry and large blocks, is about 62.0 m long. On the air side it is reinforced by pillars, five of which have been preserved. Probably in the area of the former water passage the wall on the air side has slipped down for about 10 m in length. On the water side, a thin shell of wall has been preserved. The bulwark is preserved in places up to a height of four metres.
Considerations of the highest possible water impoundment result in a wall height of about five meters, a dam length of about 130 m, a water surface of about 8500 m² and a storage volume of about 6200 m³. The purpose of the dam, apart from irrigating the fields, could have been to supply the Villa of Pisões – a Roman villa in the immediate vicinity – and an ancient canal lock. Traces of both have been found at a distance of about two kilometres from the dam wall.
- List of Roman dams
- List of dams in the world (Portugal)
Thomas G. Schattner (ed.): Archäologischer Wegweiser durch Portugal (= Cultural History of the Ancient World. Vol. 74). Philipp von Zabern, Mainz 1998, ISBN 3-8053-2313-1, p. 182.
- António de Carvalho Quintela, João Luís Cardoso, José Manuel Mascarenhas: Aproveitamentos hidráulicos romanos a sul do Tejo. Contribuição para a sua inventariação e caracterização. Ministério do Plano e da Administração do Território, Lisbon 1986, p. 75ff.