Data & Methodology — Cameron County

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

Contaminant Data — All Analytes

13708 total samples analyzed across 21 analytes. Data spans 1930 to 2023.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. PA Avg
Manganese 2 1945 50%
2400% of limit ↑ 293% above
Iron 15 1935–1961 93%
50% of limit ↓ 81% below
Sulfate 62 1930–2023 100%
9% of limit ↓ 77% below
Uranium 1 2018 100%
0% of limit ↓ 92% below
Chloride 7 1930–1945 86%
2% of limit ↓ 84% below
PFHxS municipal 4 2023 0%
0% of limit
PFNA municipal 4 2023 0%
0% of limit
PFOA municipal 4 2023 0%
0% of limit ↓ 100% below
PFOS municipal 4 2023 0%
0% of limit ↓ 100% below
HFPO-DA (GenX) municipal 4 2023 0%
0% of limit
Radon 2 2018 100%
6% of limit ↓ 97% below
Nitrate 1 1935 0%
Lead 1 1967 0%
Arsenic 1 1979 0%
Fluoride 1 1935 0%
Nitrite 1 1983 0%
Sodium 60 1935–2023 100% ↓ 91% below
pH 18 1945–2023 100% ~ typical
Fecal Coliform 1 2005 0%
Hardness 30 1998–2005 97% ↓ 59% below
PFBS municipal 4 2023 0%
↓ 100% 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.

Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Iron 15 samples
  • Sulfate 62 samples
  • Sodium 60 samples
  • pH 18 samples
  • Hardness 30 samples

Limited data (<15 samples) — interpret with caution

  • Manganese 2 samples
  • Uranium 1 sample
  • Chloride 7 samples
  • PFOA 4 samples
  • PFOS 4 samples
  • HFPO-DA (GenX) 4 samples
  • Radon 2 samples
  • Nitrate 1 sample
  • Lead 1 sample
  • Arsenic 1 sample
  • Fluoride 1 sample
  • Nitrite 1 sample
  • Fecal Coliform 1 sample
  • PFBS 4 samples

Public vs. Private Water in Cameron County

14 Active public water systems
4,333 Residents on public water
4% Households on private wells

Public water systems in Cameron 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.

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: 2026-05-28

Full methodology →