Data & Methodology — Sutter County

Full contaminant data, sample history, and sourcing for Sutter County. For readers who want to go beyond the summary.

Contaminant Data — All Analytes

411 well testing events on record, covering 27 analytes. Data spans 1951 to 2021.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. CA Avg
Manganese 130 1970–2022 62%
384% of limit ↑ 24% above
Arsenic 136 1967–2022 97%
80% of limit ↑ 105% above
Iron 139 1964–2022 38%
39% of limit ↓ 68% below
Chloride 399 1951–2022 100%
8% of limit ↓ 72% below
Nitrate 265 1957–2022 93%
8% of limit ↓ 67% below
Sulfate 271 1953–2022 99%
5% of limit ↓ 76% below
Fluoride 147 1957–2022 90%
3% of limit ↓ 62% below
PFNA municipal 20 2021–2023 0%
— —
PFOS municipal 20 2021–2023 10%
41% of limit ↓ 80% below
HFPO-DA (GenX) municipal 20 2021–2023 0%
— —
Nitrite 75 1996–2022 28%
1% of limit ~ typical
Uranium 57 1997–2022 81%
10% of limit ↑ 74% above
PFOA municipal 20 2021–2023 5%
25% of limit ↓ 85% below
Perchlorate 17 2006–2022 41%
6% of limit ~ typical
Radon 13 1996–2006 100%
8% of limit ↓ 92% below
Lead 58 1970–2022 36%
1% of limit ↓ 92% below
PFHxS municipal 19 2021–2023 5%
10% of limit ↓ 82% below
Boron 17 2006–2022 100%
7% of limit ↓ 60% below
Chromium (total) 20 2002–2022 45%
5% of limit ↑ 74% above
1,2,3-Trichloropropane 21 2002–2022 0%
— —
Tds 20 2002–2022 100%
— ~ typical
pH 396 1953–2022 100%
— ~ typical
Hardness 386 1953–2022 100%
— ~ typical
E. coli 15 2006–2021 0%
— —
Sodium 371 1953–2022 100%
— ↓ 60% below
PFBS municipal 20 2021–2023 5%
— ↓ 61% below
Total Coliform 15 2002–2021 19%
— ~ typical

Distribution shows the share of samples in each concentration band relative to the EPA Maximum Contaminant Level (MCL): Low = below half the MCL, Moderate = between half and the MCL, High = above the MCL. Analytes without an MCL (e.g. sodium, pH) show — in the limit columns. State average is based on county median values across CA.

Compare your result with Sutter County

Of the 136 arsenic tests on record for Sutter County (1967–2022), 3% found none, and half were below 8 µg/L.

Of the 399 chloride tests on record for Sutter County (1951–2022), 0% found none, and half were below 21 mg/L.

Of the 20 chromium (total) tests on record for Sutter County (2002–2022), 55% found none.

Of the 147 fluoride tests on record for Sutter County (1957–2022), 10% found none, and half were below 100 µg/L.

Of the 139 iron tests on record for Sutter County (1964–2022), 62% found none.

Of the 58 lead tests on record for Sutter County (1970–2022), 64% found none.

Of the 130 manganese tests on record for Sutter County (1970–2022), 38% found none, and half were below 30 µg/L.

Of the 265 nitrate tests on record for Sutter County (1957–2022), 7% found none, and half were below 700 µg/L.

Of the 271 sulfate tests on record for Sutter County (1953–2022), 1% found none, and half were below 12 mg/L.

Of the 20 tds tests on record for Sutter County (2002–2022), 0% found none, and half were below 460 mg/L.

Of the 57 uranium tests on record for Sutter County (1997–2022), 19% found none, and half were below 1.78 µg/L.

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Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Manganese 130 samples
  • Arsenic 136 samples
  • Iron 139 samples
  • Chloride 399 samples
  • Nitrate 265 samples
  • Sulfate 271 samples
  • Fluoride 147 samples
  • PFNA 20 samples
  • PFOS 20 samples
  • HFPO-DA (GenX) 20 samples
  • Nitrite 75 samples
  • Uranium 57 samples
  • PFOA 20 samples
  • Perchlorate 17 samples
  • Lead 58 samples
  • PFHxS 19 samples
  • Boron 17 samples
  • Chromium (total) 20 samples
  • 1,2,3-Trichloropropane 21 samples
  • Tds 20 samples
  • pH 396 samples
  • Hardness 386 samples
  • E. coli 15 samples
  • Sodium 371 samples
  • PFBS 20 samples
  • Total Coliform 15 samples

Limited data (<15 samples) — interpret with caution

  • Radon 13 samples

Public vs. Private Water in Sutter County

35 Active public water systems
87,991 Residents on public water
13% Households on private wells

Public water systems in Sutter County are regulated by the EPA and must test and report contaminant levels. Private well owners are responsible for their own testing — there is no routine monitoring of private wells by any government agency.

CDC Health Outcome Correlations

Where contaminants detected in Sutter County have established associations with specific health outcomes, we cross-reference CDC PLACES county-level prevalence data. This is a contextual signal, not a causal claim.

Contaminant Associated Condition Sutter County Prevalence CA Average Source Year
Arsenic Cancer prevalence 6.1% 6.2% 2020
Arsenic Kidney disease rate 3.1% 3.0% 2020

Source: CDC PLACES county-level estimates. Raw data: Download Sutter County CDC PLACES data →

Data Sources

This report aggregates data from the following public databases:

Methodology

Raw records are downloaded from the Water Quality Portal and normalized to µg/L (ppb). Records are deduplicated by sample ID and date, and certified outliers are excluded. Analyte names are mapped to EPA canonical forms. Detection rates, distribution bands, and MCL comparisons are computed from the normalized dataset.

Distribution bands use the EPA Maximum Contaminant Level as the threshold: concentrations below 50% of the MCL are classed as Low, between 50% and 100% as Moderate, and above 100% as High. For analytes without an MCL (sodium, hardness, pH), distribution is not computed.

State comparison uses the median of county median values across all counties in CA with at least one sample for that analyte.

Last updated: 2026-09-10

Full methodology →