Data & Methodology — Lycoming County

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

Contaminant Data — All Analytes

251 well testing events on record, covering 22 analytes. Data spans 1928 to 2023.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. PA Avg
Radon 83 2011–2022 100%
250% of limit ↑ 38% above
Manganese 132 1968–2023 77%
66% of limit ↓ 89% below
Iron 136 1935–2023 83%
53% of limit ↓ 80% below
PFOS municipal 171 2023–2025 32%
104% of limit ↑ 422% above
PFOA municipal 167 2023–2025 25%
77% of limit ↑ 518% above
Arsenic 126 1973–2023 70%
10% of limit ↓ 72% below
Chloride 141 1935–2023 100%
2% of limit ↓ 84% below
Sulfate 140 1935–2023 99%
4% of limit ↓ 91% below
Nitrate 146 1935–2023 78%
10% of limit ↑ 26% above
Fluoride 130 1968–2023 86%
2% of limit ↓ 39% below
HFPO-DA (GenX) municipal 150 2023–2025 0%
— —
Lead 117 1968–2023 54%
1% of limit ↓ 98% below
Nitrite 132 1973–2023 24%
1% of limit ~ typical
PFHxS municipal 16 2023–2025 19%
31% of limit —
PFNA municipal 16 2023–2025 19%
49% of limit —
Uranium 86 2011–2022 67%
1% of limit ↓ 60% below
E. coli 1 1998–2022 12%
— —
Hardness 134 1935–2023 100%
— ↓ 32% below
PFBS municipal 150 2023–2025 10%
— ↑ 1146% above
pH 149 1968–2023 100%
— ~ typical
Sodium 133 1968–2023 100%
— ↓ 82% below
Total Coliform 1 1998–2022 50%
— —

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.

Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Radon 83 samples
  • Manganese 132 samples
  • Iron 136 samples
  • PFOS 171 samples
  • PFOA 167 samples
  • Arsenic 126 samples
  • Chloride 141 samples
  • Sulfate 140 samples
  • Nitrate 146 samples
  • Fluoride 130 samples
  • HFPO-DA (GenX) 150 samples
  • Lead 117 samples
  • Nitrite 132 samples
  • Uranium 86 samples
  • Hardness 134 samples
  • PFBS 150 samples
  • pH 149 samples
  • Sodium 133 samples

Limited data (<15 samples) — interpret with caution

  • E. coli 1 sample
  • Total Coliform 1 sample

Public vs. Private Water in Lycoming County

133 Active public water systems
89,106 Residents on public water
22% Households on private wells

Public water systems in Lycoming 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 Lycoming 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 Lycoming County Prevalence PA Average Source Year
Arsenic Cancer prevalence 6.1% 7.0% 2020
Arsenic Kidney disease rate 2.7% 3.0% 2020

Source: CDC PLACES county-level estimates. Raw data: Download Lycoming 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: 2026-07-15

Full methodology →