Reference Document MCU22/0102 Stormwater Management Plan

6. CAR WASH STORMWATER POLLUTION CALCULATOR
To give a complete understanding of the environmental benefits of the proposed Car Wash
development, a comparison with the current car washing practises of the Cooroy Primary (PTA)
and Secondary (STA) Trade Areas need to be made. Table 10 gives a detailed population,
household size and vehicle ownership breakdown- this data has been sourced from the
Economic Needs Report.
The frequency of car washes per annum has been sourced from resources provided by the
Australian Car Wash Association (ACWA) and past surveys.
The Economic Needs Report has identified the lack of suitable Car Washing facilities in the LGA,
whereby the closest commercial Car Wash facility is around 15km away! As such, the uptake of
the local Cooroy PTA and STA using these facilities is considered to be very minor, with many
preferring to wash their vehicle at home.
Given the nature of the Cooroy PTA and STA; it is considered that only 65% of vehicles that are
being washed at home or at work would actually drain directly into the local stormwater system.
This figure would be higher in a more built-up urban area due to the higher percentage of
impermeable areas (ie: bitumen and concrete roadways and driveways) draining into the local
stormwater system.
The resultant outcome is that currently around 14.4 ML of car wash effluent water will discharge
into the local Cooroy stormwater system.




Refer to Appendix E for additional information that has been published by ACWA with regards to
the ACWA Stormwater Statement- which provides education steps within the community about
car washing, responsible vehicle washing methods, critical pollutants commonly found in car
wash effluent water etc… Also the ACWA Environmental Policy Statement is also included which
contains information about Stormwater Pollution, Water Efficiency and the public education
campaign.
Also, refer to the following link http://thedirtytruth.com.au/ which has information and videos
with regards to stormwater pollution and community education.

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