The Ramsar Convention on Wetlands, a global treaty, recognised Sawa as "unique... because it is a closed water body in an area of sabkha (salt flat) with no inlet or outlet.
"The lake is formed over limestone rock and is isolated by gypsum barriers surrounding the lake; its water chemistry is unique," says the convention's website.
A stopover for migratory birds, the lake was once "home to several globally vulnerable species" such as the eastern imperial eagle, houbara bustard and marbled duck.
Sawa is not the only body of water in Iraq facing the perils of drought.
Iraqi social media is often filled with photos of grotesquely cracked soil, such as in the UNESCO-listed Howeiza marshes in the south, or Razzaza Lake in the central province of Karbala.
In Sawa, a sharp drop in rainfall -- now only 30 percent of what used to be normal for the region -- has lowered the underground water table, itself drained by wells, said Aoun Dhiab, a senior advisor at Iraq's water resources ministry.
And rising temperatures have increased evaporation.
Dhiab said authorities have banned the digging of new wells and are working to close illegally-dug wells across the country.
Latif Dibes, who divides his time between his hometown of Samawa and his adopted country of Sweden, has worked for the past decade to raise environmental awareness.
The former driving school instructor cleans up the banks of the Euphrates River and has turned the vast, lush garden of his home into a public park.
He remembers the school trips and holidays of his childhood, when the family would go swimming at Sawa.
"If the authorities had taken an interest, the lake would not have disappeared at this rate. It's unbelievable," he said.
"I am 60 years old and I grew up with the lake. I thought I would disappear before it, but unfortunately, it has died before me."
