From Jennifer Griffin -
A senior US official tells me that there have been about 6 US airstrikes so far – the strikes are ongoing. This official says they started early this morning Iraq time.
“Critical infrstructure is on our list of things worth protecting in Iraq,” the US official said, adding the US had carried out the strikes at the request of the government of Iraq.
Further, the reason Iraq asked the US military to act now is that ISIS/ISIL cannot maintain the dam and the longer it remains in the Islamic State’s hands the greater the chance it could burst. The dam requires “daily upkeep” – especially “grouting”(?) “The longer it goes without technical support, it could fail.”
If it failed, the estimates are that 20 meters (60 feet of water) could flood Mosul and Baghdad and the US Embassy would be facing a flood of up to 4 meters (about 12 feet.) For this reason US officials say it was deemed the military must act and help the Iraq government retake the dam.