Wallamba River rises on the northern slopes of Kyle Range, near the locality of Gangat. The river flows generally east and then south, joined by five minor tributaries, before reaching its confluence with the Coolongolook River at Wallis Lake; descending 271 metres (889 ft) over its 72 kilometres (45 mi) course.
At one stage, a riverboat milk pick up service operated for the dairy farmers who farmed along the banks of the river. This service was discontinued in the mid 1970s due to economic reasons. Road milk tankers were then used to pick up from the farms.
Water skiing and fishing is popular along the Wallamba.