Can't wash cars

I recently moved into Nottinghill estate and was shocked that I am not allowed to wash my car after paying a levy of R450 for water. I spend less than 5 days at my apartment a week and at times less than 2 weeks. I find washing my car a therapy over and above caring for an expensive asset and when I queried this with management I was told it's a decision taken to minimise the water bill and that I must make use of carwashes in the area or failing which I must drive a dirty car, but washing it is a hefty fine( not in my contract) and I can't even clean the interior of my car within the premises and moving out the complex was also given to me as an option if I was not entirely happy