Melbourne's local government, schools and homeowners have successfully implemented over 10,000 rain gardens across the region in an attempt to protect its waterways.
Melbourne Water’s 10,000 Raingarden Program launched in 2008 and called for 10,000 rain gardens to be built across the Port Phillip and Westernport regions, a target which has been reached.
“Healthy waterways and abundant wildlife are an important part of maintaining Melbourne’s status as one of the world’s most liveable cities,” said Waterways general manager David Ryan. “10,000 rain gardens will go a long way to protecting local rivers and creeks for everyone to enjoy.”
The program began with local councils creating rain gardens in public urban areas to encourage homeowners to build them on their own property.
A rain garden (also called a bioretention system) differs from a regular garden bed in that it is specifically designed to capture stormwater from surfaces such as driveways and drainpipes and can even capture overflow from a rainwater tank.
Ryan says about 500 billion litres of stormwater is washed off residential roofs, driveways and roads each year, draining into waterways and the bay.
Rain gardens are becoming increasingly popular in Melbourne garden designs as the need for sustainable gardens increases.
As stormwater retention systems, rain gardens infiltrate street runoff and retain pollutants. Stormwater runoff can contain several harmful pollutants such as litter, chemicals, animal droppings and oil, which travel untreated into rivers and bays.
Stormwater entering the region’s rivers and creeks after rain can be severely problematic and lead to flooding, erosion of river banks and unfavorable conditions for plants and animals.
“Stormwater pollution is one of the biggest threats to Melbourne’s 8400km of rivers and creeks, with the problem increasing the more Melbourne grows,” said Ryan.
Rain gardens use a variety of native plants and free-draining soil to filter captured pollutants through physical and chemical processes.
There are several types of rain gardens including in-ground gardens, planter boxes, infiltration gardens, green roofs and swales.
Keysha Milenkovic, project leader for 10,000 Raingardens, says rain gardens are self-watering, easy to maintain and look great in both wet and dry seasons.
“Raingardens can take many forms and we certainly saw some very creative designs throughout this program which blended well into their surrounds, including raised planter box rain gardens and swales,” she said.
Rain gardens are self-watering, water-conserving, filter stormwater before it enters rivers and bays, reduce manual watering by directing water to planted beds, contribute to healthy waterways and maintain their aesthetics in both wet and dry seasons.
“Every rain garden makes a difference and now we have over 10,000 across Melbourne. We congratulate everyone who built a rain garden and was part of this program, and encourage more people to do the same,” Milenkovic said.
Public rain gardens can be found at several locations across Melbourne, including Edinburgh Gardens in Fitzroy, the Federation Square car park, and Lambert Street, Richmond.