REUTERS/Stringer
Extremist militants are beginning to encircle the Haditha Dam on the Euphrates River. The dam is the second largest in Iraq. If ISIS manages to seize it, they could effectively limit the Euphrates' flow to the entirety of southern Iraq - much of which is Shi'ite. ISIS is a sharply sectarian Sunni militant group.
Alissa J. Rubin and Rob Nordland, of The New York Times, write:
The ISIS militants advancing on the dam on the Euphrates River, about 120 miles northwest of Baghdad, were coming from the north, the northeast and the northwest. The fighters had already reached Burwana, on the eastern side of Haditha, and government forces were fighting to halt their advance, security officials said.
Security officers in the vicinity of the dam have reportedly been ordered to prepare to open the dam's floodgates and inundate the surrounding regions in an effort to check ISIS's advance.
ISIS has previously shown a willingness to attack Iraq's water supply. From January to April, ISIS controlled the Fallujah Dam on the Euphrates. During this time, ISIS flooded the areas around Fallujah while also cutting off water to the southern and central districts of Iraq.
There are worries that ISIS, now in control of Mosul, are in a prime position to launch an assault on the Mosul Dam. The Mosul Dam is the largest in the country, and impedes the Tigris River.
If ISIS is able to take control of both the Mosul and Haditha Dams, it will effectively be able to control the main water sources for Iraq's 32 million citizens.