Most facility managers and property owners look at their water bill just long enough to see the total and move on. That’s understandable — municipal water bills are rarely designed for clarity. But understanding a few key line items can be the difference between catching a costly problem early and paying it quietly for years.

Here’s a plain-language walkthrough of what’s actually on a typical commercial water and sewer bill.

Metered usage (the starting point for everything)

The core number on your bill is metered usage — typically expressed in hundred cubic feet (CCF) or thousand gallons. This is the figure your water utility’s meter recorded during the billing period, and it’s the basis for every other charge on the bill. It’s also the number most worth double-checking, because everything downstream assumes it’s accurate.

Water charges

Water charges are usually calculated on a tiered rate structure — the more you use, the higher the per-unit rate climbs in many municipalities (though some use flat rates). This section is where usage volume gets converted directly into dollars.

Sewer charges

This is the line item most people misunderstand. In most municipalities, sewer service isn’t separately metered — there’s no practical way to measure what goes down the drain. Instead, sewer charges are calculated as a function of your metered water intake, on the assumption that most water that comes in eventually goes out as wastewater.

This has an important consequence: if your water meter is over-reading for any reason, your sewer bill inflates right along with it. You’re not just paying once for the error — you’re paying twice, from a single inflated number.

Base or service charges

A fixed fee, usually tied to your meter size, that you pay regardless of usage. This won’t fluctuate month to month and generally isn’t the source of unexplained bill increases.

Stormwater or other municipal fees

Many municipalities tack on additional fees — stormwater management, infrastructure surcharges, or capital improvement charges. These are usually flat or based on impervious surface area rather than usage, so they’re not typically the cause of a rising bill either.

What to actually watch for

When reviewing your bill month to month or year to year, the most useful comparison isn’t the total — it’s the usage volume relative to your own operations. Ask:

• Has metered usage climbed without a corresponding change in occupancy, production, or hours of operation?
• Is the sewer charge rising in exact proportion to the water charge? (It usually should, given how it’s calculated — but if it’s rising faster than your actual operations would suggest, that’s worth investigating.)
• How does your usage per unit — per room, per employee, per square foot — compare to a prior period, or to a comparable facility?

If the answer to any of these raises a flag, the next step is a proper bill and meter review — not just adjusting the thermostat or checking for a running toilet. Meter accuracy is a real, documented variable in commercial water billing, and it’s one most facility teams have never been told to look at.

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Savings Guides: Water & Sewer Bill Review
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