Phaino
About
Roman administrators expanded the ancient copper mines at Phaino, tucked into the rugged Wadi Faynan south of the Dead Sea, into one of the empire's largest copper-producing districts after annexing the Nabataean kingdom in 106 CE. Engineers built a reservoir and dam here to store enough water for cooling and processing smelted ore, since the wadi itself ran dry for most of the year. Convicts and forced laborers, Christians exiled here for their faith among them in later centuries, kept the smelting furnaces running on water this system supplied. Dark slag heaps still blanket the valley floor today, physical evidence of just how much copper Rome pulled out of this remote corner of Arabia.
What happened here
Built to hold water for a town, a farm or a mine, and shaped by what the local rock allows: a straight wall of masonry backed with earth, or a curved one where the gorge is narrow. The core is concrete and rubble, faced in cut stone, and the upstream face is often waterproofed with mortar. Water is drawn from a tower with sluices at different heights, so the supply keeps running as the level drops and the silt stays at the bottom. Overflow channels carry the winter flood past the wall rather than over it — the detail that decides whether a dam survives. Silt is the long enemy; a reservoir has a working life and everybody involved knows it.
Sources
Nearby
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