I was sure I couldn't anyways just that I spotted this on the actew website
General Exemptions
Water can be used to wash a vehicle's windows, mirrors or lights, and for spot removal of corrosive substances, and then only with a bucket or watering can filled directly from a tap (not by means of a hose).
I would classify the amount of shit on my car as being corrosive substances although it is not really a spot removal it would be a full wash hehe
Anyways I have the best idea I don't know why I didn't think of it sooner... THERMOS... safest way to get hot water down to the car wash and it at least cleans it up nicely.