Corangamite has more than 1500 wetlands covering 63,000 ha (5% of the region). These wetlands range from large open-water saline lakes to shallow, ephemeral, freshwater meadows – many of which are rich in native flora. While 75% of the total wetland area is on public land, a large number of small wetlands are found on private land. Lake Corangamite is the largest permanent saline lake in Australia, with a surface area of 234km2 and hypersaline water – saltier than seawater.

Two wetland areas within the region, Port Phillip Bay – Western Shoreline and Bellarine Peninsula, and the Western District Lakes are recognised as Wetlands of International Importance under the Ramsar Convention. The Ramsar Convention recognises internationally significant wetlands that contain substantial biodiversity and other environmental values (including importance to waterbirds), with an agreement for their conservation. 24 wetlands in the region have been classified as Wetlands of National Importance under the Directory of Important Wetlands in Australia (DIWA). Wetlands and lakes of the Victorian Volcanic Plains were formed through volcanic craters and lava flows impacting the landscape. The diversity of the landscape and geomorphology in the area has also resulted in wide variations in salinity in the wetlands. 

Swans on Lake Connewarre

Wetlands are valued for the services they provide both to the environment and the community. These include biodiversity values, pollution control and detoxification, maintenance of water regimes, flood mitigation, commercial, recreation and tourism values, social, cultural, scientific and educational values. They can assist with climate change regulation through carbon sequestration.