Case Study 4 – Coburg and Merrifield, Stormwater Harvesting Projects, Melbourne, Australia
Melbourne, Australia is experiencing the largest population increase of all Australian capital cities. In 2011, the city’s population was 4.1 million people, and that is expected to increase by an additional 1,500 people per week, to a projected total of approximately 5 million by 2026 (Australian Bureau of Statistics, 2012). As a result, there is increased demand for residential and commercial development. Increased development leads to increased potable water demand.
Stormwater harvest and reuse can provide a sustainable urban water servicing solution as a result of potable water substitution. Galaxia’s Principal, Han Wahjudi, provided the environmental parameters, in collaboration with Dalton Consulting Engineers (DCE), to design two very different stormwater harvesting projects in the Melbourne suburbs of Coburg (159 Ha catchment) and Merrifield (1,500 ha site).
The Coburg and Merrifield stormwater harvest projects represent a major step forward in Integrated Water Cycle Management (IWCM). The knowledge gained from the projects has the potential to educate and inform other cities around the world and will be invaluable when planning how best to deliver services to a variety of growth areas. The profiled projects prove that an alternative, integrated approach to IWCM can deliver significant improvements such as reduced water consumption, reduced pollutant levels in waterways, reduced stormwater flow volumes following urbanisation and reduced energy consumption (compared to conventional supply enhancers such as desalination).