Lower Barwon wetlands

Reedy Lake and Hospital Swamps form part of the internationally recognised Port Phillip Bay (Western Shoreline) and Bellarine Peninsula Ramsar site, which is used by many thousands of migratory birds from around the world. The wetlands support 47 known threatened plant and animal species and communities. These include some of Victoria’s rarest species (such as the brolga, orange-bellied parrot, Australasian bittern, growling grass frog, Australian grayling and dwarf galaxias) and subtropical and temperate coastal saltmarsh communities. Reedy Lake also supports a range of vegetation communities, including coastal saltmarsh, herbfields and reed beds.

Reedy Lake was naturally a partly ephemeral system, but river regulation meant the lake was nearly permanently wet from the 1970s until 2016. This long-term wetting resulted in a decline in biodiversity, so wetting and drying regimes are now recommended to maintain the lake’s ecological character and diverse habitats.

Following a four-year (2016-17 to 2019-20) watering regime trial at Reedy Lake, the Lower Barwon Review in 2020 proposed to implement a long-term, seasonally adaptive water regime that avoids complete drying. At Reedy Lake, this means having the wetland full for a quarter of all years and having a partial drawdown in summer and autumn in three-quarters of all years. The review’s recommendations informed 2023-24 watering actions and future directions.

Hospital Swamps comprises five wetland basins that support important ecological processes and significant ecological values, including large areas of threatened coastal saltmarsh and diverse waterbird communities. Hospital Swamps has retained a more natural wetting and drying pattern. As a result, the swamp’s vegetation community has remained largely unchanged since the 1980s.

In planning the potential environmental watering actions in Table 3.7.3, the Corangamite CMA consulted widely with stakeholders to ensure it considered shared benefits, including social, economic and recreational values relevant to environmental flows management in the lower Barwon wetlands. Opportunities for social, recreational and economic values and uses are incorporated into planning and watering decisions if they do not compromise environmental outcomes.

Expert advice (such as the 2012 environmental flows study for the lower Barwon wetlands and the 2020 Lower Barwon Review) emphasised that the entire lower Barwon recommended watering regime – providing a fill to the wetlands and allowing water levels to draw down at the right times – would have to be implemented to improve biodiversity and protect the long-term health of the wetlands. This may mean it is not possible to meet some community expectations for shared benefits that don’t maintain or improve environmental outcomes. However, the Corangamite CMA, where possible, manages water levels in the wetlands to meet ecological requirements and also support a range of social, economic and recreational values and uses, including:

• water-based recreation (such as boating, duck hunting and fishing)
• wetlands recreation and amenity (such as birdwatching and spending time outdoors)
• community events and tourism (such as community events and Traditional Owner events)
• socioeconomic benefits (such as commercial fishing). The Corangamite CMA works with its community advisory group and stakeholders and seeks to accommodate their interests where possible while maintaining the overall health of the wetlands.