US Central Command said fighter jets and drones had destroyed or damaged four armored personnel carriers, seven armed vehicles, two Humvees and an armored vehicle.
CENTCOM “conducted these strikes under authority to support humanitarian efforts in Iraq, as well as to protect US personnel and facilities,” it added.
“Kurdish peshmerga, with US air support, have seized control of the eastern side of the dam” complex, Major General Abdulrahman Korini told the media saying several militants had also been killed.
The dam on the Tigris provides electricity to much of the region and is crucial to irrigation in vast farming areas in Nineveh province.
The recapture of Mosul dam would be one of the most significant achievements in a fightback that is slowly getting international support.
The strikes took place just a day after the brutal IS militants carried out a massacre of dozens of villagers.