Data & Methodology — St. Lucie County

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

Contaminant Data — All Analytes

591 well testing events on record, covering 23 analytes. Data spans 1923 to 2023.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. FL Avg
Radon 14 2008–2019 100%
142% of limit ↑ 383% above
PFOS municipal 14 2023–2025 43%
262% of limit ↑ 24% above
Iron 66 1923–2024 97%
82% of limit ↓ 59% below
Chloride 578 1923–2024 100%
19% of limit ↓ 61% below
PFOA municipal 14 2023–2025 21%
112% of limit ↓ 21% below
Sulfate 251 1923–2024 83%
13% of limit ↓ 51% below
Manganese 44 2008–2024 100%
7% of limit ↓ 74% below
Lead 44 2008–2024 86%
1% of limit ↓ 58% below
Nitrate 180 1923–2019 53%
0% of limit ↓ 100% below
PFHxS municipal 14 2023–2025 29%
50% of limit ~ typical
Uranium 14 2008–2019 36%
0% of limit ↓ 82% below
Arsenic 44 2008–2024 89%
2% of limit ↓ 84% below
PFNA municipal 14 2023–2025 0%
— —
Fluoride 116 1948–2024 99%
12% of limit ↑ 62% above
HFPO-DA (GenX) municipal 14 2023–2025 0%
— —
Nitrite 175 1976–2019 40%
0% of limit ↓ 76% below
pH 243 1944–2024 100%
— ~ typical
Sodium 250 1944–2024 100%
— ↓ 23% below
PFBS municipal 14 2023–2025 43%
— ↓ 21% below
Fecal Coliform 18 2017–2021 100%
— ~ typical
E. coli 16 2008–2024 67%
— ~ typical
Total Coliform 34 2008–2024 86%
— ~ typical
Hardness 220 1923–2019 99%
— ↑ 81% above

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 FL.

Compare your result with St. Lucie County

Of the 44 arsenic tests on record for St. Lucie County (2008–2024), 11% found none, and half were below 0.175 µg/L.

Of the 578 chloride tests on record for St. Lucie County (1923–2024), 0% found none, and half were below 48 mg/L.

Of the 116 fluoride tests on record for St. Lucie County (1948–2024), 1% found none, and half were below 430 µg/L.

Of the 66 iron tests on record for St. Lucie County (1923–2024), 3% found none, and half were below 230 µg/L.

Of the 44 lead tests on record for St. Lucie County (2008–2024), 14% found none, and half were below 0.2 µg/L.

Of the 44 manganese tests on record for St. Lucie County (2008–2024), 0% found none, and half were below 3.45 µg/L.

Of the 180 nitrate tests on record for St. Lucie County (1923–2019), 47% found none.

Of the 251 sulfate tests on record for St. Lucie County (1923–2024), 17% found none, and half were below 17.5 mg/L.

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Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Iron 66 samples
  • Chloride 578 samples
  • Sulfate 251 samples
  • Manganese 44 samples
  • Lead 44 samples
  • Nitrate 180 samples
  • Arsenic 44 samples
  • Fluoride 116 samples
  • Nitrite 175 samples
  • pH 243 samples
  • Sodium 250 samples
  • Fecal Coliform 18 samples
  • E. coli 16 samples
  • Total Coliform 34 samples
  • Hardness 220 samples

Limited data (<15 samples) — interpret with caution

  • Radon 14 samples
  • Uranium 14 samples

No private-well PFAS data for St. Lucie County

We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in St. Lucie County. PFAS has been detected in local public water systems (UCMR 5 data) — indicated by the "municipal" badge in the table above — but this does not directly indicate private well contamination. PFAS testing for private wells requires a dedicated lab panel (~$300–$500). If you are near a military base, airport, or industrial site, consider testing proactively. Learn more about PFAS →

Public vs. Private Water in St. Lucie County

45 Active public water systems
330,048 Residents on public water
10% Households on private wells

Public water systems in St. Lucie 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 St. Lucie 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 St. Lucie County Prevalence FL Average Source Year
PFOA Cancer prevalence 5.8% 6.8% 2020

Source: CDC PLACES county-level estimates. Raw data: Download St. Lucie 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 FL with at least one sample for that analyte.

Last updated: 2026-08-12

Full methodology →