The Koo-Wee-Rup Swamp was a large freshwater swamp located to the south east of Melbourne, Victoria. It was drained an area of West Gippsland, with several waterways including Cardinia Creek and the Bunyip River.
The Koo-Wee-Rup swamp originally covered more than 40 000 hectares, of dense swamp paperbark (Melaleuca ericifolia), some open grasslands, reed beds (Phragmites australis) and bullrushes (Typha spp). Known as The Great Swamp it was an impassable barrier for travelers between Melbourne and Gippsland. Although the fringes of the swamp were settled by the mid-1800s, farming was not possible in much of the land because of frequent flooding and the rapid re-growth of paperbark and other swamp vegetation. However, in the 1870s, efforts were made by the Victorian Department of Lands to drain the swamp and open up the area for agriculture. A Koo-Wee-Rup Swamp Drainage Committee was formed by local landowners and in February 1876 excavation of the main channel to take water from Cardinia Creek was commenced. This channel was 8 km long and 1.2 m deep, leading into Westernport Bay at Moody's Inlet. Other drains including those for Toomuc Creek and the Bunyip River were also dug.