Stormwater - Plumbing Industry Commission

Risk in using
stormwater
What you need to know about...
Stormwater
Consumer guidance from the
Plumbing Industry Commission
Risks in using stormwater
Stormwater can pose the same health risks as sewage effluent.
Depending on where the water is collected, the amount of
rainfall and time between rainfall events, the water quality
can vary dramatically.
In the first instance, plumbing practitioners should seek
advice from the Environmental Protection Authority and the
Department of Human Services on considerations surrounding
the use of stormwater.
Need more information
S The Plumbing Industry Commission technical
assistance sheets at www.pic.vic.gov.au
S Environmental Protection Authority Victoria
on (03) 9695 2722 or www.epa.vic.gov.au
S Department of Human Services
www.health.vic.gov.au
S Make Your Home Green sustainability portal
www.makeyourhomegreen.vic.gov.au
Securing a drinking water supply
A Licensed or Registered Plumbing Practitioner must install
plumbing carrying stormwater to ensure stormwater cannot
contaminate the drinking water supply.
Plumbing Industry Commission
450 Burke Road Camberwell 3124
PO Box 552 Camberwell Vic 3124
T: + 61 3 9880 6200
Toll Free: 1800 015 129
Inspections + 61 3 9835 5541
F: + 61 3 9889 2244
www.pic.vic.gov.au
The Plumbing Industry Commission promotes safe,
healthy and sustainable outcomes for all Victorians,
through an efficient plumbing regulatory system.
Copyright in the content of this document is owned by the Plumbing Industry Commission. Except as provided for
in the Copyright Act 1968, no part may be reproduced without permission. The Commission believes all information
contained in this document is accurate and reliable. However, no warranty is given as to the accuracy or reliability
of the information and the information must not be regarded as legal advice. The Commission (its employees and
agents) accept no liability for any loss or damage that any person may incur arising from, or related to, reliance upon
the information or from its use.
Printed October 2008 on recycled paper

What is stormwater Collecting stormwater. Using stormwater.
Stormwater is rainwater that falls on the ground or on paving,
driveways or hard surfaces within a property, overflows from tanks
and roof guttering. This water can be captured and pumped back
for use.
What can stormwater be used for
Stormwater can carry a wide range of pollutants,
including sediment, oil, hydrocarbons and leaves.
As a result of this, stormwater can only be used for:
S Toilet flushing
S Sub-surface and surface irrigation.
Stormwater must never be used for human
consumption, washing, cleaning and cooking
or mixed with water intended for such use.
Stormwater should be used only where it has been captured solely
from the user’s property, and where the property is clean, with no
loose soil or chemical contamination (e.g. from petrol or diesel).
When designing a stormwater capture and re-use project,
a Licensed or Registered Plumbing Practitioner must consider:
S collection systems
S storage options
S treatment requirements
S distribution methods
S the eventual use for the water
S obtaining necessary approvals.
Where possible, stormwater should not be
stored in a device that is also used to store
rainwater. However, if stormwater and
rainwater are stored together, this water
must only be used for low risk purposes
such as garden watering and toilet flushing.
As with any recycled water, it is important to match the
intended use of stormwater with the quality of the water.
Storage
Where possible, stormwater should not be stored in a
device that is also used to store rainwater. However, if
stormwater and rainwater are stored together, this water
must only be used for low risk purposes such as garden
watering and toilet flushing.
Additionally, stormwater and grey water should never be
stored together. Untreated grey water should not be stored
for more than 24 hours as it can turn septic. Stormwater
over flow can go back into the stormwater drainage system,
while grey water over flow needs to be discharged into the
sewerage system.
Treatment
Stormwater should always be treated before use. The risk
of collecting contaminated water should be assessed at
the outset when designing the stormwater re-use system.
Generally, the more likely the water is to come into
direct human contact, the more treatment and prevention
is needed.
Stormwater to be re-used for irrigation, for example, may
need to be applied through sub-surface drippers rather
than surface sprinklers, and you can not irrigate food crops.