US-backed Syrian fighters paused their offensive near the Tabqa dam on Monday to let engineers check it and fix any damage affecting operations.
The Syrian Democratic Forces alliance is battling so-called Islamic State for control of the structure, which is on the River Euphrates west of Raqqa. On Sunday, the US-led coalition against IS denied claims by the group that air strikes have damaged the dam.
But its former chief engineer warned the control room was “out of service”. The UN has warned that if the dam were to collapse, it could lead to flooding on a “massive scale” across Raqqa province and as far downstream as Deir al-Zour with “catastrophic humanitarian consequences”(BBC,2017).