Tyler Street Raingarden

A raingarden is a special type of garden bed that is designed specifically to receive and filter rain run-off from hard surfaces such as streets, driveways, paving and gutters.

The raingarden comprises of a series of layers, allowing water to collect and settle on the garden surface before soaking through to the plants and filter media.

The top layer is planted with native plants and grasses that are able to tolerate long periods without rain, and large inundations at other times. These plants have deep, fibrous and spreading root systems, taking up water and nutrients as the water moves through the system. A layer of large pebbles on the surface of the raingarden helps to trap litter and sediment.

Below the surface, layers of soil, sand and organic material (known as bioretention media) work to filter the stormwater of toxins. Layers of sand and gravel also help drain water to the lower levels. You can see images here that show what the bioretention media looks like, when it was installed.

As water filters through the raingarden, it percolates through the layers, where contaminants from the street are slowly trapped. Larger particles are generally trapped in the top layers, with smaller particles trapped within the lower levels. At the lowest level is a slotted pipe, where the cleaned, filtered water can exit the raingarden and is drained to the Merri Creek.

The Tyler Street raingarden consists of the following layers:

Top layer
Deep rooted plants consisting of kangaroo paw, sedges, club rush, hollow rush, mat rush and cushion bush for raingardens.

Middle layers
Boulders, gravel mulch, bioretention media.

Bottom layer
Crushed rock laying over a slotted drain connected to stormwater system.

2014    
Melbourne Water Living River funding received for design and construction

2015  
Design is finalised by Melbourne Water and Darebin City Council.

Construction of raingarden and travel safety features.

2017    
Interpretative signage installed.

$33,000 (Melbourne Water and in-kind project management from the City of Darebin).

Maintenance includes weeding, large litter removal and replacing plants and substrate as required.

The rain garden provides an attractive and greener streetscape for residents, with the added advantage of slowing traffic and creating a safer walkway for pedestrians and bicycle users.

The installed interpretive signage explains how raingardens works, which helps to educate the community on water sensitive urban design benefits. This signage also provides education for the nearby Preston Primary School students.

Many animals and insects call our local creeks and waterways home, such as the platypus, rakali (our native water rat), water bugs, frogs, fish and birds (such as the Sacred Kingfisher). Our waterways provide food and habitat for these and other animals and plants, so it is important we keep them safe and clean.

When it rains, contaminants washed from our streets end up in the waterways. These contaminants include those we can see, such as plastics and cigarette butts, but also include those we can’t see, such as oils, detergents, bacteria and pesticides. Contaminants pollute our waterways, resulting in a direct negative health impact on our local aquatic wildlife and plants.

Raingardens clean, filter and separate water from contaminants, before the water enters our creeks, rivers and ultimately the ocean. Raingardens slow down the speed that stormwater enters our waterways, reducing problems of erosion (loosening of soil) on creek banks. Slowing the speed at which water enters our waterways helps to improve our overall stream water quality.

Darebin City Council acknowledges the Wurundjeri people as the traditional owners and custodians of this land and pays respect to their Elders past and present.

Artwork infographics developed and supplied by the City of Melbourne. For other examples of WSUD Urban stormwater treatment projects visit the City of Melbourne Urban Water Interactive Map here.

Melbourne Water – Living Rivers Program