# Non-revenue water

URL: https://municorn.us/glossary/non-revenue-water/
Updated: 2026-08-09
Tags: water, glossary, revenue

> **Cite as:** Municorn.us, "Non-revenue water", Municorn water loss index, https://municorn.us/glossary/non-revenue-water/ (source filings retrieved 2026-08-09).
> **Licence:** CC BY 4.0 — https://creativecommons.org/licenses/by/4.0/ — reuse and redistribution are permitted with attribution to Municorn.us and a link to this URL.
> **Caveat that must travel with these figures:** "Water loss" is at least three different quantities depending on the jurisdiction, and nothing here supports a comparison between states.

Water a utility produced and paid to treat but never billed anyone for, split into the part that is a revenue problem and the part that is a cost problem.

Non-revenue water is everything that entered a distribution system and produced no bill. It is not the same as leakage, and treating the two as synonyms is expensive in a specific way: it values water that was delivered and not billed at the cost of water that never arrived.

## The four components

A water audit divides system input into four parts, and the division is the whole point:

- **Billed authorized consumption.** Water that reached a customer and appeared on an invoice.
- **Unbilled authorized consumption.** Firefighting, main flushing, municipal use. Real water, deliberately not billed.
- **Apparent loss.** Water that reached a customer and was never billed. Under-registering meters, data-handling errors between the meter and the bill, unauthorized connections.
- **Real loss.** Water that never reached a customer. Leaks, main breaks, storage overflows.

Non-revenue water is the last three added together. That sum is a useful headline and a useless action item, because the three have nothing in common operationally.

## Why the split decides what you do about it

Apparent loss is a revenue problem. The water was delivered and consumed; only the billing failed. Recovering it means fixing meters and billing records, it shows up in the next cycle, and it needs no capital budget.

Real loss is a cost problem. The water never reached anyone, so there is no invoice to recover. Eliminating it saves what it cost to treat and pump, not what it would have sold for. Fixing it means finding and repairing pipe, which is a capital program on a multi-year horizon.

A study that values both at the retail rate overstates the recoverable amount, because only the apparent-loss share could have been billed.

## What a percentage does not tell you

A ten percent loss rate on a system selling 20 billion gallons a year is worth far more than a thirty percent rate on one selling 200 million. Percentages rank systems by how bad they look; dollars rank them by what is worth acting on. Recoverable dollars is the only ordering that maps onto a decision.

_Municorn.us · https://municorn.us/glossary/non-revenue-water/ · CC BY 4.0 https://creativecommons.org/licenses/by/4.0/ · source filings retrieved 2026-08-09_

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