Data & Methodology — Lafayette County

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

Contaminant Data — All Analytes

893 well testing events on record, covering 17 analytes. Data spans 1960 to 2025.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. FL Avg
Nitrate 555 1990–2002 94%
76% of limit ↑ 2246% above
Iron 207 1993–2025 98%
3% of limit ↓ 98% below
Manganese 207 1993–2025 98%
2% of limit ↓ 92% below
Arsenic 199 2002–2025 100%
6% of limit ↓ 52% below
Chloride 754 1990–2025 100%
4% of limit ↓ 93% below
Fluoride 227 1990–2025 96%
3% of limit ↓ 58% below
Lead 199 2002–2025 100%
1% of limit ↓ 67% below
Nitrite 557 1990–2002 46%
2% of limit ↑ 60% above
Radon 1 2002 100%
7% of limit ↓ 77% below
Sulfate 363 1990–2025 100%
4% of limit ↓ 85% below
Uranium 1 2002 100%
3% of limit ↑ 165% above
Total Coliform 19 2002–2025 100%
— ~ typical
Sodium 230 1990–2025 100%
— ↓ 95% below
pH 860 1990–2025 100%
— ~ typical
Hardness 32 1990–2002 100%
— ↓ 21% below
Fecal Coliform 11 1990–2020 34%
— ~ typical
E. coli 8 2002–2025 100%
— ~ 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 FL.

Compare your result with Lafayette County

Of the 199 arsenic tests on record for Lafayette County (2002–2025), 0% found none, and half were below 0.628 µg/L.

Of the 754 chloride tests on record for Lafayette County (1990–2025), 0% found none, and half were below 9.14 mg/L.

Of the 227 fluoride tests on record for Lafayette County (1990–2025), 4% found none, and half were below 120 µg/L.

Of the 207 iron tests on record for Lafayette County (1993–2025), 2% found none, and half were below 9.83 µg/L.

Of the 199 lead tests on record for Lafayette County (2002–2025), 0% found none, and half were below 0.158 µg/L.

Of the 207 manganese tests on record for Lafayette County (1993–2025), 2% found none, and half were below 1 µg/L.

Of the 555 nitrate tests on record for Lafayette County (1990–2002), 6% found none, and half were below 5.99 mg/L.

Of the 363 sulfate tests on record for Lafayette County (1990–2025), 0% found none, and half were below 10 mg/L.

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Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Nitrate 555 samples
  • Iron 207 samples
  • Manganese 207 samples
  • Arsenic 199 samples
  • Chloride 754 samples
  • Fluoride 227 samples
  • Lead 199 samples
  • Nitrite 557 samples
  • Sulfate 363 samples
  • Total Coliform 19 samples
  • Sodium 230 samples
  • pH 860 samples
  • Hardness 32 samples

Limited data (<15 samples) — interpret with caution

  • Radon 1 sample
  • Uranium 1 sample
  • Fecal Coliform 11 samples
  • E. coli 8 samples

No private-well PFAS data for Lafayette County

We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Lafayette County. 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 Lafayette County

9 Active public water systems
3,064 Residents on public water
86% Households on private wells

Public water systems in Lafayette 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 Lafayette 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 Lafayette County Prevalence FL Average Source Year
Nitrate Cancer prevalence 6.8% 6.8% 2020

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