Ada River rises below Marney Hill, northeast of Powelltown, in a state forestry area, and flows generally northeast, then south by east, before reaching its confluence with the Latrobe River, north of the Yarra Junction-Noojee Road, west of the locality of Noojee in the Shire of Baw Baw. The river descends 546 metres (1,791 ft) over its 14-kilometre (8.7 mi) course.[2]
The Ada River sub-catchment area is managed by the West Gippsland Catchment Management Authority.