Environment Matters Autumn/Winter 2023

Constructing a living wetland

When stormwater runs off our urban roads, roofs, and other hard surfaces it takes a range of pollutants with it. From rubbish to chemicals, nutrients to sediment, there are a lot of things that can cause damage when they get into our waterways. Constructed wetlands can be an effective tool in treating urban stormwater runoff by acting as a filter, stripping the water of these pollutants before the water reaches creeks and rivers. Often these constructed wetlands need to be ‘retrofit’ into an existing urban environment. The design needs to be sensitive to local conditions such as soils, hydrology and vegetation and tailored to the type and concentration of target pollutants. NEW CONSTRUCTED WETLANDS COMING SOON Projects are funded through council’s Stormwater Quality Offsets Scheme. Bremervale Park, Raceview Council is designing an ephemeral wetland next to Bundamba Creek for construction in 2024. The ‘ephemeral’ design is a shallow depression which dries out 26 tonne per year of total suspended solids 43kg per year of total phosphorous 90kg per year of total nitrogen Harry Ratnam Park, Redbank Plains construction in 2024. The wetland will improve the environment and help reduce urban heat island effect. Pollutant reduction goals: 10 tonne per year of total suspended solids 16kg per year of total phosphorous 39kg per year of total nitrogen shortly after a rain event. Pollutant reduction goals: Council is designing a permanent wetland near Goodna Creek for

Dense buffer Thick native vegetation provides a safety buffer between the urban area and the wetlands

Diverse habitat

Native plants provide food and shelter for a variety of species including frogs and birds

Capture pollutants Grasses and sedges filter nutrients such as phosphorous, nitrogen as well as sediment from urban runoff

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