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Rainwater Tanks

2200 litre water tank, Park Crescent Child Care Centre

Saving Water

Do you know how much water can be collected from the average house roof?

When 1mm of rain falls onto 1 square metre of roof space, it collects a litre of water. So if it rains 10 mm per hour for one hour, then 10 litres of water will result.

Therefore, a 200 square metre roof will have collected 2,000 litres of water in a single hour! Rainwater can be safely used for garden watering, car washing, toilet flushing or other similar activities, taking pressure off our water supplies.

Rainwater tanks come in various materials, shapes and colours. Sizes can vary from as small as 100 litres to over 40,000 litres.

Rainwater collected in suburban areas is not recommended for drinking as quality is affected by factors including:

  • Pollution from birds and possums
  • Atmospheric pollution from industry
  • Contamination from roof and gutter coatings
  • Residues from solid fuel heaters

This water may also contain harmful bacteria, viruses and parasites which can cause gastroenteritis if consumed.

Council Requirements

The installation of a rainwater tank must be conducted by a licensed plumber. An overflow pipe needs to be re-directed to the storm water drain.

The tank must operate separately from the reticulated water supply to prevent backflow of the tank water into the mains water supply.

All openings of the tank must be properly screened to prevent mosquito breeding.

Council provides the following suggestions for the placement of tanks:

  • Tanks should be located at the side or rear of existing buildings and screened from view from the street and surrounding properties.
  • Tanks are not to be located within 0.5 metres of a boundary.
  • Tanks should be located to avoid loss of trees and significant vegetation as well as minimising the need for earthworks or soil disturbance. (Note - removal of trees and/or other vegetation and earthworks may also require a Planning Permit.)
  • Where it is not possible to screen the tank from view, the placement, size, height, colour and materials of the tank should not detract from existing buildings, garden settings, landscapes and views.

Do I need a building permit for a water tank?

A building permit or planning permit may be required before you install a water tank. Check our water tanks page for planning and building requirements for rainwater tanks and download our Water Tanks brochure.

Should you require any further information about water tanks, please call our Building and Planning Department on 9298 8125.

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