Waikawa River  The Waikawa River flows east then south through the Catlins, an area of the southern South Island of New Zealand. Its total length is , and it flows into the Pacific Ocean at Waikawa. Close to its mouth, it cascades over a small series of cataracts, ironically named Niagara Falls. The river's source is east of Fortrose. The New Zealand Ministry for Culture and Heritage gives a translation of "bitter water" for .