The Collie River in Western Australia runs 154 kilometres from its source in the Darling Range to the Leschenault Estuary near Bunbury, roughly two hours south of Perth. The river meanders through suburbs, forest, and farmland, offering considerable variety along its length. It holds significant cultural importance to the Nyungar people, who regard it as a sacred waterway and a registered mythological site under the Aboriginal Heritage Act 1972. The river is associated with the Waugal, a serpent deity central to Noongar spiritual tradition.

The river divides naturally into distinct paddling characters depending on location. The upper reaches above Collie town and below Wellington Dam are suited to moving water and whitewater paddling, particularly in winter and spring when flows are higher. The section below Wellington Dam is described as a popular paddlers' playground in summer. Minningup Pool, within Wellington National Park, is a calm Grade 1 location used for guided family kayak tours covering distances of 3 to 6 kilometres. Honeymoon Pool is another noted spot in the upper river, though paddlers should be aware that downstream of the second drop there are grade three rapids, a weir, irrigation canals, and a section where the river disappears underground — paddlers are advised not to continue past that point and to return upstream instead.

The lower river, from the Eaton foreshore toward the Leschenault Estuary, offers flat-water paddling. The Eaton to The Cut kayak trail is a 4-kilometre return route starting from the boat ramp at Eaton on Old Coast Road. Along this stretch paddlers pass the Grand Canals, Pelican Point, an osprey nest on the northern bank, and Bar Island at the rivermouth. Dolphins are frequently seen in this area. The river mouth opens to the Leschenault Estuary, which provides access to The Cut and the ocean beyond. The estuary supports a wide range of birdlife including black swans, pelicans, cormorants, ibis, and the critically endangered Eastern Curlew.

Boat ramps are available at the Collie River Bridge (Taylor Road, Pelican Point), the Eaton Foreshore (Pratt Road, Eaton), the Elbow Reserve (Barnes Avenue, Australind), and Ridley Place (Paris Road, Australind). The Eastwell Boat Ramp Precinct also provides launch access in the lower river area. Water level and flow are important planning considerations, particularly in the upper river, where conditions can change quickly following rainfall.