Alarms were triggered minutes before a swollen, fast-moving stream fed by heavy rains approached the World Heritage site of Petra, according to Hussein al-Hasanat of the Petra Development & Tourism Region Authority, cited by ABC News.
Hundreds of tourists quickly sought high ground to avoid the dangerous torrent of muddy water. A video posted online showed visitors running through a narrow canyon leading to the Treasury, Petra’s most well-known tourist attraction, as guides assisted. Many tourists were later evacuated, ABC reported.
The most recent fatal flash flood in Petra struck in 1963, killing 22 French tourists and a local guide. All 23 drowned in rapidly rising flood waters. After the tragedy, Jordan's Department of Antiquities built a dam to keep water from entering the canyon that leads to the Treasury. In 2014 local authorities installed an alarm system which would switch on sirens if flood waters rise above a certain level.
The system was triggered for the first time on November 9, by use of a computer in the Petra Authority's control room. The computer, connected to eight rain forecast systems and two water detection stations, is within 8 kilometres of Petra. The systems provide data allowing officials to measure possible danger and warn visitors in advance.
Omar Dajani, a meteorologist at the Arabia Weather company, suggested that alarms should be installed in all vulnerable areas in Jordan as rising urbanization in the country has exacerbated the flood risk, already particularly high in dry areas.
“Now towns have spread so much and many of them were not built with respect for the geography of the region, such as valleys for example, where the water has naturally caused floods for millions of years,” Dajani said.