The 11 News I-Team is raising new questions about the accuracy and reliability of Baltimore City's water billing program.The I-Team has learned that a big condominium project that has been open for almost 10 years only recently received a bill.The I-Team has learned that the board of the well-known Ritz Carlton on Key Highway in Federal Hill repeatedly requested billing from the city's Department of Public Works but only recently were any bills sent.The project consists of nearly 200 units, making it one if the city's larger water customers. DPW has not answered the I-Teams questions about why the project went so long with being billed.Water rights activists said the city's inability to properly bill such a big customer is another example of the longstanding problems with accurate billing."The problem is a lot of customers receive erroneous bills. They have no way to dispute those bills. They have bills they can't afford to pay, and the assistance available isn't meeting their needs," said Mary Grant, with Public Water for All.Activists have compiled a list of hotels and office buildings in Baltimore that have large unpaid balances on their accounts.The mayor's office told the I-Team it is aware of some of the big billing issues and will address them.Longtime DPW Director Rudy Chow announced last week he will retire in February.