 The southern Poerua River flows from its headwaters in the Southern Alps to the Tasman Sea near Harihari.The river is a trout and salmon fishing location and its mouth is where it is met by the Hinatua River and is located roughly a kilometre south of the Wanganui River's mouth.On the morning of 6 October 1999, a landslide from Mount Adams blocked the Poerua River, creating a landslide dam about 11 km upstream from the State Highway 6 bridge over the river.