The effectiveness of Albany’s 260 square metre native rain garden in dealing with stormwater continues to exceed expectations.

Results collected by our project partner, Landcare Research, after six heavy rain events show that the quality and volume of stormwater leaving the rain garden continues to be a vast improvement on what flowed in to it.

Acting as a sponge, the garden soaks up large volumes of water and consistently releases it into the stormwater system at a far slower rate. Controlling sudden increases in water volumes prevents scouring and erosion further downstream.

On one occasion, 95 litres of water a second entered the rain garden and was soaked up with only half a litre a second being released into the stormwater system.

Similarly, the garden is consistently preventing huge amounts of sediment and heavy metals from entering the stormwater system and flowing into our streams and the sea.

The garden has been so efficient at removing phospherus from the water that it is below detection levels in the water leaving the garden. The rain garden plants are growing well and the garden will continue to be monitored during another 10 heavy rain events.