The Ötztaler Ache is a right tributary of the Inn River in the Imst (district) and flows through the Ötztal valley with a length of appr. 35 km. It merges with the Inn River 8 km east of Imst. The river is one of the biggest tributaries with plenty of water. The dangerous water of the river devastated the valley several times but nevertheless rafting – fans love the whitewater.