Rainwater Tanks

We encourage Stonnington residents to install rainwater tanks to make better use of our water resources.


You don’t need a planning permit for a domestic rainwater tank with a capacity of less than 4,500 litres unless:

  • The property is located in a heritage overlay, and
  • The tank would be visible from a street or public open space

You don’t need a building permit for a freestanding domestic rainwater tank, as it is not classified as a building.

However, you do need a building permit if the tank is structurally supported by a building, in which case structural adequacy and wall setback allowances need to be checked.


Your rainwater tank must be fitted with an overflow pipe of the same diameter as the inlet pipe. The overflow pipe must be connected to a stormwater drainage system that discharges to a legal discharge point.


There are potential health risks associated with drinking unfiltered water from rainwater tanks. The Department of the Environment and Primary Industries has a lot of good information about rainwater tanks, including water quality and rebates available.


The State Government of Victoria has introduced a rebate scheme for ‘waterwise’ products. Rebates are available for the following products:

  • Dual-flush toilet
  • Washing machine with 5-star water (WELS) and 4-star energy ratings
  • Pool cover with roller/reel
  • Water-efficient showerhead
  • Permanent greywater system
  • Rainwater tanks meeting Australian Standards connected to toilet and/or laundry (depending on size)
  • Rainwater tank to toilet/laundry connection
  • Water conservation audit
  • Hot water recirculator device
  • Basket of goods