Folsom - Main
What Folsom - Main 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
- 13.1% Computed from filed system input and billed consumption.
- system input volume 6,103 sheet Sheet1, cell AN2791 · converted to million gallons from acre-feet
- billed authorized consumption 5,304 sheet Sheet1, cell AQ2791 · billed metered plus billed unmetered, converted to million gallons from acre-feet
- Recoverable annually
- $395,000 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.
- cost of apparent losses, as filed 395,001 sheet Sheet1, cell DH2791
- Balance check
- inapplicable DWR derives water losses from system input minus authorized consumption, so this decomposition holds by construction.
2026-09-05-f0dfea5a6026.csvSheet1 AN2791
Where this figure comes from
(system input − billed authorized) ÷ system input × 100
From data/archive/ca-dwr-water-loss/2026-09-05-f0dfea5a6026.csv (SHA-256 f0dfea5a6026881d), retrieved 2026-09-05 from the published source.
2026-09-05-f0dfea5a6026.csvSheet1 DH2791
Where this figure comes from
cost of apparent losses + cost of real losses, both as computed in the filed audit
From data/archive/ca-dwr-water-loss/2026-09-05-f0dfea5a6026.csv (SHA-256 f0dfea5a6026881d), retrieved 2026-09-05 from the published source.
What the record shows
13.1% non-revenue water in FY2024, higher than 68% of the 545 California systems that filed that year.
- The figure is improving across the record.
What it charges
$29.15 a month for a household using 6 hundred cubic feet — 4,488 gallons — and $56.73 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 $20.09 a month before any water is used. Billing is monthly, quoted in hundred cubic feet.
- Tier 1, up to 20 hundred cubic feet — $1.51 per hundred cubic feet
- Tier 2, 20 to 40 hundred cubic feet — $1.61 per hundred cubic feet
- Tier 3, above 40 hundred cubic feet — $1.75 per 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 CA3410014
- Volumetric tiers WRSFUsageCost1, WRSFUsageCost2, WRSFUsageCost3, system CA3410014
- Tier tops WRSFMetricUsage1, WRSFMetricUsage2, WRSFMetricUsage3, system CA3410014
- Unit of measure WRUOM, system CA3410014
- Billing frequency WRFrequency, system CA3410014
- The Board's own charge field WR6HCFDWCharges, system CA3410014
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 1 is health-based. 4 resolved, 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
Folsom City Of filed 2 separate audits for FY2024, one for each public water system it operates, and this page is one of them. California keys its water loss export on the filing organization and not on the system, so a count of California audits is not a count of independent utilities. Folsom City Of made one set of decisions and filed it 2 times. Read any statewide figure with that in mind, including the ones on this site.
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.
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 6,103 MG sheet Sheet1, cell AN2791 · converted to million gallons from acre-feet
- Billed authorized 5,304 MG sheet Sheet1, cell AQ2791 · billed metered plus billed unmetered, converted to million gallons from acre-feet
- Unbilled authorized 33.3 MG sheet Sheet1, cell AW2791 · unbilled metered plus unbilled unmetered, converted to million gallons from acre-feet
- Apparent loss 191.2 MG sheet Sheet1, cell CC2791 · converted to million gallons from acre-feet
- Real loss 574.3 MG sheet Sheet1, cell CE2791 · 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.
| Year | NRW | Input (MG) | Recoverable |
|---|---|---|---|
| 2024 | 13.1% | 6,103 | $395,000 |
| 2023 | 13.5% | 5,675 | $647,000 |
| 2022 | 13.7% | 5,728 | $388,000 |
| 2021 | 11.3% | 5,822 | $362,000 |
| 2020 | 13.1% | 6,081 | $364,000 |
| 2019 | 14.5% | 5,722 | $275,000 |
| 2018 | 15.1% | 5,895 | $277,000 |
| 2017 | 17.3% | 6,277 | $294,000 |
| 2016 | 20.7% | 5,795 | $277,000 |
Comparable systems
The same size band — 10,000–50,000 connections.
| System | Basis for comparison | NRW |
|---|---|---|
| San José - Evg/edv/coy | 10,000–50,000 connections | 9.1% FY2024 |
| Redwood City | 10,000–50,000 connections | 6.1% FY2025 |
| Santa Cruz | 10,000–50,000 connections | 6.5% FY2024 |
| Padre Dam Municipal Water District | 10,000–50,000 connections | 2.0% FY2025 |
| Cws Pv Palos Verdes | 10,000–50,000 connections | 4.2% FY2024 |
| Merced | 10,000–50,000 connections | 8.4% FY2024 |
| Palo Alto | 10,000–50,000 connections | 5.1% FY2024 |
| Cws Sln Salinas | 10,000–50,000 connections | 6.6% FY2024 |
Where is it going?
This page says how much — roughly $395,000 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 Folsom - MainSources 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.
- California DWR — urban retail water supplier water loss audits, filed under Water Code section 10608.34. Retrieved 2026-09-05 from data/archive/ca-dwr-water-loss/2026-09-05-f0dfea5a6026.csv. https://data.cnra.ca.gov/dataset/d6cdd89e-49b0-4b1f-86ee-8b7237e5f169/resource/058ac6ca-a8b4-4f28-b6c8-11e48309f3b4/download/ca-retailer-waterlossdata.csv