Data & Methodology — Newaygo County

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

Contaminant Data — All Analytes

7809 total samples analyzed across 19 analytes. Data spans 1971 to 2018.

Contaminant Samples Years Detection Rate Distribution LowModHigh vs. Limit vs. MI Avg
Iron 46 1974–2002 100%
42% of limit ↓ 79% below
PFOA municipal 18 2025 11%
0% of limit
PFNA municipal 18 2025 0%
0% of limit
Uranium 1 1979 100%
0% of limit ↓ 60% below
Nitrite 21 1999–2009 95%
1% of limit ↓ 27% below
Chloride 41 1971–2018 100%
6% of limit ↓ 48% below
Sulfate 32 1971–2011 97%
6% of limit ↓ 65% below
PFOS municipal 18 2025 0%
0% of limit
PFHxS municipal 18 2025 0%
0% of limit
HFPO-DA (GenX) municipal 18 2025 0%
0% of limit
Fluoride 11 1974–2012 100%
3% of limit ↓ 65% below
Manganese 7 1974–1975 86%
32% of limit ↓ 77% below
Arsenic 3 1974–1979 67%
15% of limit ↓ 53% below
PFBS municipal 18 2025 22%
Lead 1 1974 0%
Nitrate 1 1979 0%
Fecal Coliform 1 1980 0%
pH 9 1974–2013 89% ~ typical
Sodium 34 1974–2013 100% ↓ 65% 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 MI.

Data Coverage & Gaps

Well-sampled analytes (15+ samples)

  • Iron 46 samples
  • PFOA 18 samples
  • PFNA 18 samples
  • Nitrite 21 samples
  • Chloride 41 samples
  • Sulfate 32 samples
  • Sodium 34 samples

Limited data (<15 samples) — interpret with caution

  • Uranium 1 sample
  • Fluoride 11 samples
  • Manganese 7 samples
  • Arsenic 3 samples
  • Lead 1 sample
  • Nitrate 1 sample
  • Fecal Coliform 1 sample
  • pH 9 samples

Public vs. Private Water in Newaygo County

148 Active public water systems
32,254 Residents on public water
36% Households on private wells

Public water systems in Newaygo 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 Newaygo 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 Newaygo County Prevalence MI Average Source Year
PFOA Cancer prevalence 6.1% 7.2% 2020

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

Last updated: 2026-05-27

Full methodology →