It flows southwest from the slopes of Mount Taranaki to reach the Tasman Sea at Ōpunake.

The New Zealand Ministry for Culture and Heritage gives a translation of "waters containing herring" for Waiaua.

[1] Aua is usually translated as yellow-eye mullet.

[2] "Place name detail: Waiaua River".

This article about a river in Taranaki is a stub.