Briefed by the City of Melbourne to implement a precinct scale stormwater harvesting system and to develop an enhanced public landscape for Birrarung Marr, the design team has delivered in abundance.

Concealed under the renewed landscape of the upper terrace of Birrarung Marr, Melbourne’s most recent major park, is an underground tank equal to the size of an Olympic pool. The 2.5 megalitre two-part tank is part of a sophisticated stormwater harvesting and treatment system delivered by Cardno, Urban Initiatives and Jones & Whitehead in late 2013.

The system intercepts runoff from 37ha of Melbourne’s CBD as well as the adjacent railway land, and diverts this water to a storage tank and then through a bio-retention filter bed set on the highest ground of the upper terrace.

The filtered water then drains under gravity to a 500kL reuse tank below, where it is stored for use in irrigation. Final irrigation water is UV disinfected before use. The system provides up to 35ML of potable water offset per annum.

Key initiatives:

  • The capture, treatment and reuse of approximately 35 million litres of stormwater annually (runoff from 37 hectares of Melbourne’s CBD)
  • A high output system (large volumes treated) on a relatively small, well designed footprint
  • The creation of an irrigation source for the long term sustainability of the 8 hectare park that will keep green the upper and middle terraces of Birrarung Marr, the historic landscape of Speaker’s Comer and the trees along the banks of the Yarra River
  • The integration of a large water processing facility into a high amenity value, major urban park
  • Creating a visible landscape feature in the form of the formal bio-filtration bed, set on a commanding terrace at the top of the park
  • Capitalising on the insertion of this infrastructure by redesigning the upper terrace landscape for improved amenity and better connections in the park

Images: Drew Echberg