Data & Methodology — Bradford County

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

Contaminant Data — All Analytes

359 well testing events on record, covering 22 analytes. Data spans 1935 to 2024.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. PA Avg
Radon 80 2013–2022 100%
212% of limit ↑ 64% above
Manganese 245 1975–2023 82%
120% of limit ↓ 76% below
Iron 257 1935–2023 81%
63% of limit ↓ 89% below
Arsenic 241 1975–2023 61%
11% of limit ↓ 62% below
Chloride 252 1935–2023 100%
4% of limit ↓ 63% below
Lead 210 1975–2023 41%
1% of limit ↓ 75% below
Nitrate 261 1935–2023 69%
3% of limit ↓ 81% below
Sulfate 257 1935–2023 97%
6% of limit ↓ 64% below
Fluoride 244 1970–2023 80%
4% of limit ~ typical
HFPO-DA (GenX) municipal 59 2024–2025 0%
— —
Nitrite 252 1981–2023 42%
0% of limit ↓ 93% below
PFHxS municipal 10 2024–2025 0%
— —
PFNA municipal 10 2024–2025 0%
— —
PFOA municipal 95 2024–2025 2%
54% of limit ↓ 42% below
PFOS municipal 95 2024–2025 1%
98% of limit ↓ 23% below
Uranium 113 2012–2022 86%
2% of limit ↓ 29% below
PFBS municipal 59 2024–2025 12%
— ~ typical
Hardness 185 1935–2023 100%
— ~ typical
E. coli 73 1998–2022 8%
— ~ typical
Total Coliform 72 1998–2022 49%
— ~ typical
Sodium 252 1935–2023 100%
— ~ typical
pH 270 1970–2023 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 PA.

Compare your result with Bradford County

Of the 241 arsenic tests on record for Bradford County (1975–2023), 39% found none, and half were below 0.46 µg/L.

Of the 252 chloride tests on record for Bradford County (1935–2023), 0% found none, and half were below 9.72 mg/L.

Of the 244 fluoride tests on record for Bradford County (1970–2023), 20% found none, and half were below 100 µg/L.

Of the 257 iron tests on record for Bradford County (1935–2023), 19% found none, and half were below 100 µg/L.

Of the 210 lead tests on record for Bradford County (1975–2023), 59% found none.

Of the 245 manganese tests on record for Bradford County (1975–2023), 18% found none, and half were below 31.1 µg/L.

Of the 261 nitrate tests on record for Bradford County (1935–2023), 31% found none, and half were below 40 µg/L.

Of the 85 pfoa tests on record for Bradford County (2025), 98% found none.

Of the 85 pfos tests on record for Bradford County (2025), 99% found none.

Of the 257 sulfate tests on record for Bradford County (1935–2023), 3% found none, and half were below 15 mg/L.

Of the 113 uranium tests on record for Bradford County (2012–2022), 14% found none, and half were below 0.34 µg/L.

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Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Radon 80 samples
  • Manganese 245 samples
  • Iron 257 samples
  • Arsenic 241 samples
  • Chloride 252 samples
  • Lead 210 samples
  • Nitrate 261 samples
  • Sulfate 257 samples
  • Fluoride 244 samples
  • HFPO-DA (GenX) 59 samples
  • Nitrite 252 samples
  • PFOA 95 samples
  • PFOS 95 samples
  • Uranium 113 samples
  • PFBS 59 samples
  • Hardness 185 samples
  • E. coli 73 samples
  • Total Coliform 72 samples
  • Sodium 252 samples
  • pH 270 samples

Public vs. Private Water in Bradford County

90 Active public water systems
38,361 Residents on public water
64% Households on private wells

Public water systems in Bradford 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 Bradford 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 Bradford County Prevalence PA Average Source Year
Arsenic Cancer prevalence 8.4% 7.0% 2020
Lead Heart disease rate 9.1% 7.2% 2020
Arsenic Kidney disease rate 3.6% 3.0% 2020

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

Last updated: 2026-08-04

Full methodology →