Data & Methodology — Cumberland County

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

Contaminant Data — All Analytes

558 well testing events on record, covering 20 analytes. Data spans 1923 to 2024.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. PA Avg
Iron 146 1925–2023 79%
60% of limit ↓ 90% below
Manganese 137 1957–2023 67%
89% of limit ↓ 82% below
Radon 49 1994–2019 100%
9% of limit ↓ 93% below
PFOS municipal 239 2023–2026 28%
152% of limit ~ typical
PFOA municipal 238 2023–2026 25%
96% of limit ~ typical
Nitrate 348 1925–2023 98%
55% of limit ↑ 207% above
Lead 58 1969–2023 12%
0% of limit ↓ 100% below
Arsenic 47 1974–2023 32%
5% of limit ↓ 83% below
Chloride 149 1925–2023 100%
6% of limit ↓ 48% below
Fluoride 142 1957–2023 77%
5% of limit ~ typical
HFPO-DA (GenX) municipal 189 2023–2026 0%
— —
Nitrite 311 1974–2023 12%
1% of limit ↓ 60% below
PFHxS municipal 60 2023–2025 2%
35% of limit ↓ 24% below
PFNA municipal 60 2023–2025 0%
— —
Sulfate 148 1925–2023 100%
9% of limit ↓ 47% below
Uranium 47 1994–2021 38%
1% of limit ↓ 39% below
pH 424 1951–2023 100%
— ~ typical
PFBS municipal 189 2023–2026 19%
— ~ typical
Hardness 149 1925–2023 100%
— ↑ 66% above
Sodium 151 1925–2023 98%
— ↓ 64% below

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 Cumberland County

Of the 47 arsenic tests on record for Cumberland County (1974–2023), 68% found none.

Of the 149 chloride tests on record for Cumberland County (1925–2023), 0% found none, and half were below 14 mg/L.

Of the 142 fluoride tests on record for Cumberland County (1957–2023), 23% found none, and half were below 200 µg/L.

Of the 146 iron tests on record for Cumberland County (1925–2023), 21% found none, and half were below 80 µg/L.

Of the 58 lead tests on record for Cumberland County (1969–2023), 88% found none.

Of the 137 manganese tests on record for Cumberland County (1957–2023), 33% found none, and half were below 10 µg/L.

Of the 348 nitrate tests on record for Cumberland County (1925–2023), 2% found none, and half were below 5.41 mg/L.

Of the 178 pfoa tests on record for Cumberland County (2025–2026), 70% found none.

Of the 179 pfos tests on record for Cumberland County (2025–2026), 72% found none.

Of the 148 sulfate tests on record for Cumberland County (1925–2023), 0% found none, and half were below 22.9 mg/L.

Of the 47 uranium tests on record for Cumberland County (1994–2021), 62% found none.

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Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Iron 146 samples
  • Manganese 137 samples
  • Radon 49 samples
  • PFOS 239 samples
  • PFOA 238 samples
  • Nitrate 348 samples
  • Lead 58 samples
  • Arsenic 47 samples
  • Chloride 149 samples
  • Fluoride 142 samples
  • HFPO-DA (GenX) 189 samples
  • Nitrite 311 samples
  • Sulfate 148 samples
  • Uranium 47 samples
  • pH 424 samples
  • PFBS 189 samples
  • Hardness 149 samples
  • Sodium 151 samples

Public vs. Private Water in Cumberland County

101 Active public water systems
249,523 Residents on public water
31% Households on private wells

Public water systems in Cumberland 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 Cumberland 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 Cumberland County Prevalence PA Average Source Year
Nitrate Cancer prevalence 7.5% 7.0% 2020
Lead Heart disease rate 5.3% 7.2% 2020

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