Coordinates: 32°36′19″S 115°38′24″E / 32.60528°S 115.64000°E
Dawesville Channel (also known as Dawesville Cut) is a man-made channel between the Peel-Harvey Estuary and the Indian Ocean at Dawesville about 80 km south of Perth in Western Australia. It is just south of the regional city of Mandurah and just north of Yalgorup National Park.
The channel was constructed to alleviate an environmental problem which had developed where much of the 136 km², two metre deep estuarine system had become eutrophic. The adjoining estuaries' ability to support the natural flora and fauna had become seriously degraded and the smell of rotting algae, particularly during the summer months had caused increasing complaints from residents. Stocks of the normally abundant fish and crabs had become depleted and recreational use was impacted. The deteriorating environmental situation became a major political and environmental issue for the Government of Western Australia during the mid-1980s.
The channel allows seawater from the Indian Ocean to regularly flush in and out of the estuary using the daily tidal movements which in turn prevent the buildup of algae.