Recently the sewer bill for my apartment came (it apparently only comes once every 3 months). My lease states I am responsible for hot/cold water, electricity, and heat. It also says that the landlord will take care of the lawn and the leaves (although this was added in pen later). It does not mention anywhere who is responsible for the sewer.

My landlord claims that I am responsible for paying the sewer bill. Her reasoning is that both the sewer and water bill are calculated using the same meter thus the sewer and water are the same utility and, since I am responsible for the water, I must also pay for the sewer. She also says that tenants are always responsible for all of their utilities (but there is no clause in the lease like this) so I have to pay for it regardless.

My claim is that the water and sewer bills are separate and come from two different utility companies, and they provide difference services - thus they are separate utilities. Therefore, I am not responsible for paying for this bill because it is not stated in my lease.

So who is right? I am willing to take this as far as I need to go, but I'd rather not waste anyone's time if there is a clear answer that I am just not aware of. Thanks!
Additional Details
According to Connecticut (where I live) Landlord/Tenant law,
"Unless the rental agreement states that the tenant is
responsible, the landlord must supply running water
and reasonable amounts of heat and hot water."
http://www.jud.state.ct.us/Publications/hm031.pdf
So, by law, the landlord is responsible for heat and water (and possibly sewer then?) unless otherwise specified.

All of my other leases with previous landlords have specified who pays for both the sewer and water -- they have always both been listed on the lease. This is the first one that hasn't.

As far as the water and sewer being the "same" bill, why do they come separately from different companies? The two companies don't even serve all of the same areas. They just happen to overlap where I live.