Complaint Review: Philadelphia water revenue bureau

I own a property in Philadelphia, I moved out and have been trying to sell it for 2 years now. The house was broken into, copper pipes and water meter stolen. So I finally get around to having the pipes put in and the water meter so a prospective buyer can have an inspection done. The water company was made aware on several occasions the house was vacant. They even turned off the water at the curb at some point. Now they are trying to bill me for a years worth of water usage (which is just some number they make up) right as settlement approaches. I have never been late or behind on any of my bills and have continued to pay the customer charge and storm water charges. Never once in any conversation with these people did they indicate that at some point they would come up with some fraudulent and fictitious number to try and extort from me. I know I'm not the only one they are trying to extort money from. Something needs to be done, it's not like you can choose who provides your water thus leaving these people to do as they please. I need to know what actions I can take because I'm not paying them for services not rendered.