Fighting puts Syria IS-held dam at 'risk of collapse'
The ongoing clashes at Tabqa dam have damaged its power station, forcing a halt to operations on Sunday, risking dangerous rising water levels.
A Kurdish-Arab alliance known as the Syrian Democratic Forces [SDF] is battling to take Tabqa dam and nearby Tabqa town from IS before advancing on the group's de facto Syrian capital Raqqa.
"The dam is designed to hold a certain amount of water and if its floodgates are closed this will increase the water levels and could exceed the pressure the dam can withstand," civil engineer, Mounir Suwaid, told The New Arab.
"The dam has a spillway to get rid of excess water but it cannot discharge all of it," Suwaid said.
He played down the danger that the dam would collapse because of excess water levels, however, he added that the continued air raids could weaken the dam and lead to a disaster.
"The biggest danger lies in the repeated airstrikes and shelling near the dam, which could crack the dam's structure," the engineer said.
IS ordered residents to evacuate the Syrian city of Raqqa on Sunday following reports on its propaganda agency Amaq that the dam "is threatened with collapse at any moment because of American strikes and a large rise in water levels."
Civilians began fleeing midday, according to the activist-run Raqqa is Being Slaughtered Silently.
Local activist Abo Sham warned that two million people were at risk of losing their lives and homes if the dam collapsed.
"The SDF has been shelling around the dam for around a month and in recent days the offensive has escalated," Abo Sham wrote on Facebook.
"The dam has cracks in it because of a lack of maintenance, its old age and IS' inability to manage it. If its floodgates close it will surely collapse," he added.
Earlier this month, the UN's humanitarian coordination agency OCHA said water levels in the Euphrates had risen 10 metres since late January, in part from heavy rainfall and snow.
But it warned that damage to the dam "could lead to massive scale flooding across Raqqa and as far away as Deir Az-Zour" province to the southeast.
Any further rises in the water level or damage to the Tabqa dam "would have catastrophic humanitarian implications in all areas downstream," the UN warned.