It flows north from its source near Te Koraha through Hauturu to Kawhia Harbour.

[10] It is threatened by weed invasion, forest degradation and goat and possum browse.

[11] Awaroa Scenic Reserve, at the river's estuary,[12] covers 692.84 ha (1,712.0 acres)[13] and has the fern Ophioglossum coriaceum, the orchid Bulbophyllum tuberculatum and the mistletoe Peraxilla tetrapetala.

[14] The estuary upstream from Uenukutuhatu Rock has mangrove, seagrass, freshwater marsh clubrush and regenerating bush, with invasive black locust trees.

[18] A 1981 report said the willows didn't hinder navigation, but launches could only go as far as the road bridge.