‘Wai’—‘water’ and ‘Kawa’—‘bitter’, thus ‘Bitter Water’.
The bitter taste of the water is attributed to material brought down in a slip in the upper reaches of the Waikawa River. At one stage, tasting the water below the slip irritated the throat but nowadays the Waikawa is not particularly bitter.
It is also the only river in Horowhenua that has two names. Kaitawa, above the slip, meaning ‘surest water’, and Waikawa, ‘bitter water’, below.
The mouth and the lower reaches have changed course many times, often causing serious erosion. An earlier Waikawa resident recalls “… a Maori legend about a large Taniwha which lurked in the Waikawa river and possessed powers to change the course of the river.”