Full contaminant data, sample history, and sourcing for Carver County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
124 well testing events on record, covering
19 analytes.
Data spans 1952 to 2023.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. MN Avg
Iron
101
1961–2013
100%
540% of limit
↓ 24% below
Manganese
28
1961–2013
100%
387% of limit
↓ 21% below
Arsenic
83
1994–2013
93%
49% of limit
↓ 43% below
Sulfate
98
1961–2013
100%
17% of limit
~ typical
Chloride
112
1961–2013
99%
0% of limit
↓ 94% below
Fluoride
98
1961–2013
98%
6% of limit
~ typical
HFPO-DA (GenX)
municipal
16
2023–2025
0%
—
—
Lead
83
1994–2013
90%
0% of limit
↓ 99% below
Nitrate
107
1961–2013
84%
0% of limit
↓ 100% below
Nitrite
83
1974–2013
12%
0% of limit
↓ 62% below
PFHxS
municipal
16
2023–2025
0%
—
—
PFNA
municipal
16
2023–2025
0%
—
—
PFOA
municipal
16
2023–2025
0%
—
—
PFOS
municipal
16
2023–2025
0%
—
—
Uranium
71
1980–2013
96%
2% of limit
↓ 52% below
Sodium
97
1961–2013
100%
—
~ typical
pH
23
1961–2013
100%
—
~ typical
PFBS
municipal
16
2023–2025
0%
—
—
Hardness
15
1961–2013
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 MN.
Compare your result with Carver County
Of the 83 arsenic tests on record for Carver County (1994–2013),
7% found none, and half were below 4.2 µg/L.
Of the 112 chloride tests on record for Carver County (1961–2013),
1% found none, and half were below 1.14 mg/L.
Of the 98 fluoride tests on record for Carver County (1961–2013),
2% found none, and half were below 237 µg/L.
Of the 101 iron tests on record for Carver County (1961–2013),
0% found none, and half were below 1.62 mg/L.
Of the 83 lead tests on record for Carver County (1994–2013),
10% found none, and half were below 57 ng/L.
Of the 28 manganese tests on record for Carver County (1961–2013),
0% found none, and half were below 193 µg/L.
Of the 107 nitrate tests on record for Carver County (1961–2013),
16% found none, and half were below 8 µg/L.
Of the 98 sulfate tests on record for Carver County (1961–2013),
0% found none, and half were below 42.1 mg/L.
Of the 71 uranium tests on record for Carver County (1980–2013),
4% found none, and half were below 0.54 µg/L.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Iron 101 samples
Manganese 28 samples
Arsenic 83 samples
Sulfate 98 samples
Chloride 112 samples
Fluoride 98 samples
Lead 83 samples
Nitrate 107 samples
Nitrite 83 samples
Uranium 71 samples
Sodium 97 samples
pH 23 samples
Hardness 15 samples
No private-well PFAS data for Carver County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Carver County.
PFAS testing for private wells requires a dedicated lab panel (~$300–$500). If you are near a military base, airport, or industrial site, consider testing proactively. Learn more about PFAS →
Public vs. Private Water in Carver County
67Active public water systems
104,689Residents on public water
15%Households on private wells
Public water systems in Carver 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 Carver 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.
This report aggregates data from the following public databases:
Water Quality Portal (WQP) — groundwater sample results for Carver County from EPA, USGS, and state agencies. Browse WQP data →
EPA Safe Drinking Water Information System (SDWIS) — public water system inventory used to estimate the share of residents on private wells. Browse SDWIS →
Census ACS 5-Year Estimates — well and cistern household counts (variable DP04_0074E) used to calculate the private-well percentage for Carver County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Carver County, which informs which contaminants are geologically likely. USGS Aquifer Atlas →
EPA UCMR 5 (2023–2025) — PFAS occurrence data from public water systems, used as a proxy indicator for aquifer PFAS exposure. Rows marked "municipal" in the table above come from this source. About UCMR 5 →
EPA Toxics Release Inventory (TRI) — industrial facility chemical releases near Carver County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Carver County, used in contamination risk scoring. Superfund site search →
CDC PLACES — county-level health outcome prevalence (kidney disease, cancer, heart disease) correlated with detected contaminants. About CDC PLACES →
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 MN with at least one sample for that analyte.