Legal Question in Landlord & Tenant Law in California

You have to look at what your rental contract states. If it does not discuss the issue but if it clearly states that you will be obligated to pay X.Y,Z and that does not include water and sewer services, then you are not responsible. If that is not clearly spelled out, you have to look at what is the custom and practice as to rental properties, especially ones with a single meter. It is more difficult to determine who used what if there is only one meter [can look to see usage when back house not in usage] and how the base charge, which is often a significant percentage of the total, is to be handled. But remember, unless you are under rent control or a more than month to month tenancy, the landlord can raise the rent after giving 30 days notice by having you pay those charges.