Garbh Uisge is a river of approximately 7 km in the Trossachs of Scotland just north-west Callander. It is the outflow of Loch Lubnaig and joins with Eas Gobhain west of Callander to form the River Teith. The name of the river, Garbh Uisge, is Gaelic for "Rough Water", reflecting the nature of the river.