Are rainwater tanks required for a dual occupancy?
Not necessarily. A dual occupancy must demonstrate compliance with the ACT’s applicable water-efficiency requirements, including a target of 40% reduction in mains water use compared with an equivalent development constructed in 2003.
ACT Planning treats dual occupancy as multi-unit residential development for this assessment—the Multi-unit Waterways Calculator specifically covers developments from dual occupancy through to multi-storey apartments. The calculator considers rainwater tanks alongside other water-saving measures, including water-efficient fixtures and greywater systems.
Therefore, a rainwater tank is not automatically required simply because the development is a dual occupancy. A tank may form part of the design used to demonstrate compliance with the required water-efficiency target.
Reference: ACT Planning, Water Efficiency – https://www.planning.act.gov.au/professionals/regulation-and-responsibilities/responsibilities/water-efficiency
Short Answer
Not automatically. A dual occupancy must meet the applicable 40% mains-water-use reduction target, but a rainwater tank is not stated as mandatory solely because the development is a dual occupancy. It can be one of the measures used to achieve the required water-efficiency outcome.
Detailed Explanation
There is no universal requirement identified by ACT Planning that every dual occupancy must install a rainwater tank. Rather, dual occupancy falls within the multi-unit residential water-efficiency assessment, and the development must demonstrate the applicable 40% mains-water-use reduction target.
The Multi-unit Waterways Calculator accounts for rainwater tank information, greywater systems, water-efficient fixtures, roof area, landscaping and impervious surfaces in assessing water consumption. Accordingly, rainwater harvesting may be used as part of the compliance strategy but is not, by itself, stated as mandatory for every dual occupancy.
No minimum block size does not remove the need for planning assessment.
Would you like to know what these rules mean for your property?
Get a Planning Assessment prepared by our experienced planning team.