Currently, the Casey RACE re-uses onsite rainwater collected from the CILC’s existing roof and treated pool backwash water to substitute potable water consumption for pool “top-ups”, toilet flushing, showering and landscape irrigation. From the 10 million litres normally used for backwash, approximately 75% are now recycled.

In this constant effort for water conservation and sustainability design, the City of Casey sort to identify opportunities for a green roof and additional IWM options for the site. This study aimed to deliver a complete investigation of IWM options for the precinct including the completion of a business case illustrating the costs and benefits to each stakeholder, a shortlisting of ranked options and recommendations for suitable IWM option(s) incorporated as part of the future redevelopment plan.

Building on the existing works, the aim of the project was the delivery of a clear and comprehensive IWM option study. Our team of experts worked collaboratively on the Green Roof and Green Wall options, the identified IWM options and modelled their performance in MUSIC, the financial analysis and the engagement and presentation to a stakeholder group.

Water Technology analysed the water balance of the site, taking into account changes in density due to development, to define the current and future water use. The demand/supply modelling was undertaken, where input data was supplied from background information and derived MUSIC models. An Integrated Water Management options study investigated the feasibility and benefits of various alternative water supply options, including rainwater harvesting, and treatment systems such as green roof and green wall, bioretention systems and wetlands. A cost-benefit analysis of each of the options was undertaken and recommendations made to provide a suitable integrated water management option.