California · PWS CA5010017

Patterson, City Of

What Patterson, City Of filed with DWR about the water it produced and the water it billed for, 2016–2024 — and what the filing does and does not let anyone verify.

Non-revenue water, FY2024
10.9%
Computed from filed system input and billed consumption.

2026-09-05-f0dfea5a6026.csvSheet1 AN4430

Where this figure comes from

(system input − billed authorized) ÷ system input × 100

  • system input volume 1,267 sheet Sheet1, cell AN4430 · converted to million gallons from acre-feet
  • billed authorized consumption 1,129 sheet Sheet1, cell AQ4430 · billed metered plus billed unmetered, converted to million gallons from acre-feet

From data/archive/ca-dwr-water-loss/2026-09-05-f0dfea5a6026.csv (SHA-256 f0dfea5a6026881d), retrieved 2026-09-05 from the published source.

Recoverable annually
$88,900
Apparent loss is valued at this utility's own reported retail price of water. Real loss is NOT included — DWR publishes a variable production cost whose unit it does not declare, so no dollar figure is put on the leaked water. The real recoverable total is higher than this by an amount this filing does not let anyone state.

2026-09-05-f0dfea5a6026.csvSheet1 DH4430

Where this figure comes from

cost of apparent losses + cost of real losses, both as computed in the filed audit

  • cost of apparent losses, as filed 88,886 sheet Sheet1, cell DH4430

From data/archive/ca-dwr-water-loss/2026-09-05-f0dfea5a6026.csv (SHA-256 f0dfea5a6026881d), retrieved 2026-09-05 from the published source.

Balance check
inapplicable
DWR derives water losses from system input minus authorized consumption, so this decomposition holds by construction.

What the record shows

10.9% non-revenue water in FY2024, higher than 57% of the 545 California systems that filed that year.

10.9% non-revenue water in FY2024, against 545 California filings for the same yearA strip of 545 filings on a 0 to 64% axis. The median is 9.2%. This system is 10.9%. 1 filing above 64% are drawn at the right edge.0%10%20%30%40%50%60%This system 10.9%California median 9.2%
The reported figure is not stable enough to act on. It has moved an average of 6.2 points a year, against a California median of 2.6, including 10% to 21% between FY2020 and FY2021. A distribution system's real losses do not change that fast — pipe does not deteriorate or repair itself in a single year. A series that moves like this is describing how the water is being measured and recorded, not how much of it is being lost, and which year is closer to true cannot be settled from this filing.

What it charges

$34.62 a month for a household using 6 hundred cubic feet — 4,488 gallons — and $98.31 at 17,952 gallons. Computed from the fixed charge and the tiers this system filed for reporting year 2025, not read off a rate sheet.

The fixed charge is $17.46 a month before any water is used. Billing is monthly, quoted in hundred cubic feet.

Where this figure comes from

fixed charge + each tier's price over the part of 6 HCF that falls in it

  • Fixed charge WRSFCostPerUOM1, system CA5010017
  • Volumetric tiers WRSFUsageCost1, WRSFUsageCost2, system CA5010017
  • Tier tops WRSFMetricUsage1, WRSFMetricUsage2, system CA5010017
  • Unit of measure WRUOM, system CA5010017
  • Billing frequency WRFrequency, system CA5010017
  • The Board's own charge field WR6HCFDWCharges, system CA5010017

From data/archive/ca-ear-rates/2026-09-09-6eba0fd85f1f-section8-charges.jsonl, extracted 2026-09-09 from the Board's published section 8a file. That file has no cells: a value is found by the system identifier and the question abbreviation above.

The Board also publishes an undocumented charge field for this volume. Our figure reproduces it to the cent, which is what establishes that the field is a bill at this volume for systems like this one.

This is what the system reported for reporting year 2025. It is not necessarily the rate in force today, and nothing in the filing says whether it has since changed.

Source: California State Water Resources Control Board, electronic Annual Report 2025, section 8a, filed under Health and Safety Code section 116530. How every California bill on this site compares.

Compliance record

4 violations on EPA's record for this system as of 2026Q2, of which 3 are health-based. 3 resolved, 1 archived, and 0 still open.

Nothing on the record is open as of 2026Q2.

Counted as distinct violations, not as rows: EPA's export carries one row per enforcement action taken against a violation, so a row count would multiply this system's record several times over. A violation here is a breach of a reporting, monitoring or contaminant-level rule as reported to EPA — it is not a measurement of the water, and this site has none.

Source: US EPA, Safe Drinking Water Information System, via the ECHO national download, 2026Q2. How we hold it.

Who filed this audit

Patterson City Of filed this audit for FY2024 and operates no other system in the export that year. California keys its export on the filing organization and not on the system, so the two coincide here rather than by definition.

Every figure on this page is read from DWR's published export as this site holds it: a 184-column extract of DWR's 190-column file. Six columns naming individuals, including the contact and the third-party validator, are removed before the bytes are committed, so the click path behind each figure lands on the extract and not on DWR's original. The column letters differ from DWR's for that reason.

Water balance, FY2024 · 1,267 MG system input
Billed 1,129 MG Unbilled authorized 2.82 MG Apparent loss 17 MG Real loss 117.9 MG

DWR derives water losses from system input minus authorized consumption, so these parts sum to the whole on every filing. What a filing can get wrong is which of these numbers were measured.

Where these volumes come from
  • System input 1,267 MG sheet Sheet1, cell AN4430 · converted to million gallons from acre-feet
  • Billed authorized 1,129 MG sheet Sheet1, cell AQ4430 · billed metered plus billed unmetered, converted to million gallons from acre-feet
  • Unbilled authorized 2.82 MG sheet Sheet1, cell AW4430 · unbilled metered plus unbilled unmetered, converted to million gallons from acre-feet
  • Apparent loss 17 MG sheet Sheet1, cell CC4430 · converted to million gallons from acre-feet
  • Real loss 117.9 MG sheet Sheet1, cell CE4430 · converted to million gallons from acre-feet

From data/archive/ca-dwr-water-loss/2026-09-05-f0dfea5a6026.csv (SHA-256 f0dfea5a6026881d), retrieved 2026-09-05 from the published source.

Filed history, 2016–2024
Year NRW Input (MG) Recoverable
2024 10.9% 1,267 $88,900
2023 18.6% 1,255 $124,000
2022 14.7% 1,266 $117,000
2021 21.4% 1,316 $125,000
2020 9.5% 1,254 $122,000
2019 18.5% 1,181 $38,400
2018 15.7% 1,203 $40,100
2017 18.9% 1,176 $34,400
2016 14.2% 1,030 $19,700

Comparable systems

The same size band — 3,300–10,000 connections.

SystemBasis for comparisonNRW
Pphcsd3,300–10,000 connections 13.6% FY2025
Mountain House3,300–10,000 connections 17.6% FY2024
Twentynine Palms Water District3,300–10,000 connections 6.7% FY2024
Bellflower Somerset Mutual Water Co3,300–10,000 connections 3.1% FY2024
Lac Wwd No. 40 - Regions 24/27/33/35/38/393,300–10,000 connections 8.2% FY2024
Cws Wlk Westlake3,300–10,000 connections 6.2% FY2024
Valley Of The Moon Water District3,300–10,000 connections 5.3% FY2025
Riverbank3,300–10,000 connections 17.4% FY2024

Where is it going?

This page says how much — roughly $88,900 a year. It cannot say which accounts, which zones, or which meters. That takes your billing history, your meter reads, and your production data reconciled against each other.

Our Water Loss Recovery Snapshot is three weeks, one flat fee, and the deliverable is a ranked list of specific accounts and zones with dollars and a confidence on each.

See what the Snapshot delivers Email us about Patterson, City Of

Sources and corrections. Every figure above is either filed by the utility or computed from filed figures, and each one says which. If a number here is wrong, it is either wrong in the filing or wrong in our reading of it — tell us which and we will correct the page and say what changed.

Cite as

Municorn.us, “Patterson, City Of — water loss as filed”, Municorn water loss index, https://municorn.us/water-loss/ca/patterson-city-of/ (source filings retrieved 2026-09-05).

CC BY 4.0 — reuse and redistribution are permitted with attribution to Municorn.us and a link to this page. Terms, and the one 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.