# Integrated Water Management 1.1 Potable Water Use
# Applies to
All development
# Objective
To reduce total potable water use due through the use of efficient fixtures, appliances, and the use of rainwater.
# Summary
Points are awarded when the annual internal potable (mains) water consumption has been reduced by at least 25% against the reference case, as calculated by the in-built calculator or demonstrated via alternative modelling. More points are awarded for each improvement with a 40% score awarded for 25% reduction, and maximum score awarded for projects achieving 70% reduction or higher.
Efficient fixtures and appliances, rainwater use and recycled water use are included in the estimated potable water consumption for this credit. Refer to the Water Efficiency Labelling Scheme (WELS) to select fixtures and appliances or confirm the WELS rating for each item.
# Rainwater results
The results table for this credit displays some information that may be useful to optimise rainwater systems. These results should be interpreted together.
Note that the calculations use monthly average rainfall and daily average household water consumption. Performance and reliability will depend on actual conditions and behaviour.
- % of connected demand met by rainwater. If this result is 100% or near 100%, consider whether there are other uses that could also be connected. If this result is significantly lower than 100%, consider whether it is possible to increase the catchment area and tank storage volume.
- How often deos the tank overflow? If the rainwater tank is overflowing regularly, consider increasing the tank size and/or increasing the connections to rainwater (if possible).
- Opportunity for additional rainwater connection (kL). If this is greater than zero, then there is water use suitable for connection to rainwater that is not currently connected. Interpret this with the results above to understand whether your existing system can service this demand or whether increasing the catchment area or tank volume would also be required.
For example:
- If you have opportunity for additional rainwater connection, your tank is overflowing often, and you are already meeting the demand that is connected - you should consider connecting more uses (e.g. toilets) to your rainwater tank.
- If you have opportunity for additional rainwater connection but you are not meeting demand that is already connected - improve this first by either increasing the catchment area (roof connected to tanks) or the tank storage volume.
# Documentation & evidence required
Site / Floor plans showing:
- Notation regarding water efficient fixtures and appliances
- Rainwater tank(s), drawn at the correct size and labelled as connected to (X) number of toilets, irrigation or other re-use opportunities.
- Roof catchment area and connection to which tank
# Other Considerations
Applicants are encouraged to consider additional water saving strategies not currently included within the tool scoring, for example:
- Locating hot water units close to the point of use to reduce heat loss through pipes.
- Locating wet areas (bathrooms and laundries) and kitchens adjacent to each other
# Further Information
- WELS – Water Efficiency Labeling and Standards Scheme: (opens new window)
- NCC Plumbing Code of Australia: (opens new window)
- Rainwater Harvesting Association of Australia (opens new window)
- Rainwater use in urban communities. Guidelines for Non-drinking Applications in Multi-residential, Commercial and Community Facilities (opens new window)