You are lucky -- are Taxachusetts charge is $4.19/hcf for water and $6.38/hcf for sewer (total of $10.57/hcf) if you use more than 20 hfc/quarter. And if you use more than 70 hcf/quarter you pay $5.03 for water and $7.66 for sewer (total of $12.69/hcf).
You see here in the land of Kennedy and Kerry, even water is "taxed" progressively.
In our town, you pay the sewer even when watering lawns. So, in the summer when we exceed 70 hcf/quarter, we are paying 1.7 cents per gallon.
In fact, I am seriously considering putting in a well (at least for non-drinking consumption) even though we live in a near-city suburb since I figure the payback will be less than 5 years.