Water Bills Are Two Bills

Most utilities bill water and sewer separately: a water charge for what comes in, a sewer charge for what goes out — often 80–100% of the same volume at a higher rate. On top sit fixed fees for meter service and infrastructure. The calculator reproduces that structure, so the number you see is the bill's actual anatomy, not a single vague "water cost."

Usage Drives Everything

At 80 gallons per person per day, a family of three uses 7,200 gallons per 30-day cycle. Because both water and sewer rates apply to that volume, every gallon saved cuts two line items at once — which is why fixing a running toilet (up to 200 gallons a day) pays for itself in a single billing cycle.

Forecast Before the Bill Arrives

Plug in last month's actual usage and your utility's rates, and you get next month's bill before the meter reader does. The same model answers "what would a leak cost" or "how much does a summer lawn add" — change the per-person usage and watch water, sewer, and the total move together.