The US military launched a wave of air strikes in northern Iraq just over a week ago with the stated aim of protecting a group of Yazidi minority refugees and preventing an IS advance on the city of Erbil.
US President Barack Obama said last week that the siege of the Yazidi civilians has been broken, but strikes have only intensified as US-backed Kurdish and Iraqi forces try to secure the key dam.
"Since August 8, US central command has conducted a total of 68 airstrikes in Iraq. Of those 68 strikes, 35 have been in support of Iraqi forces near the Mosul Dam," the statement said.
Monday's barrage destroyed nine IS fighting positions and a checkpoint, six armed trucks, an armored vehicle, a mobile anti-aircraft gun and a patch of ground booby-trapped with improvised explosives.
Central command said the strikes had been conducted under the authority of Obama's order to support Iraqi and Kurdish forces in the fight against IS militants and to protect US personnel and facilities.