Full contaminant data, sample history, and sourcing for Chambers County. For readers who want to go beyond the summary.
Contaminant Data — All Analytes
708 well testing events on record, covering
20 analytes.
Data spans 1935 to 2023.
Contaminant
Samples
Years
Detection Rate
Distribution LowModHigh
vs. Limit
vs. TX Avg
Chloride
438
1935–2014
100%
109% of limit
↑ 206% above
Manganese
116
1958–2021
94%
95% of limit
↑ 48% above
Iron
186
1948–2021
89%
67% of limit
↓ 57% below
Nitrate
138
1941–2014
78%
15% of limit
↓ 33% below
Arsenic
109
1990–2021
33%
32% of limit
~ typical
Sulfate
412
1935–2014
99%
2% of limit
↓ 94% below
Lead
103
1990–2021
8%
8% of limit
↓ 55% below
Fluoride
358
1941–2021
99%
18% of limit
↓ 27% below
HFPO-DA (GenX)
municipal
12
2023–2025
0%
—
—
Nitrite
19
1994–2014
5%
0% of limit
↓ 61% below
PFHxS
municipal
12
2023–2025
0%
—
—
PFNA
municipal
12
2023–2025
0%
—
—
PFOA
municipal
12
2023–2025
0%
—
—
PFOS
municipal
12
2023–2025
0%
—
—
Radon
8
2002–2014
100%
9% of limit
↓ 75% below
Uranium
65
1994–2021
34%
7% of limit
↓ 57% below
Sodium
41
1941–2014
100%
—
↑ 81% above
pH
65
1949–2014
100%
—
~ typical
PFBS
municipal
12
2023–2025
25%
—
~ typical
Hardness
396
1935–2014
100%
—
↓ 27% 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 TX.
Compare your result with Chambers County
Of the 109 arsenic tests on record for Chambers County (1990–2021),
67% found none.
Of the 438 chloride tests on record for Chambers County (1935–2014),
0% found none, and half were below 274 mg/L.
Of the 358 fluoride tests on record for Chambers County (1941–2021),
1% found none, and half were below 700 µg/L.
Of the 186 iron tests on record for Chambers County (1948–2021),
11% found none, and half were below 155 µg/L.
Of the 103 lead tests on record for Chambers County (1990–2021),
92% found none.
Of the 116 manganese tests on record for Chambers County (1958–2021),
6% found none, and half were below 43.5 µg/L.
Of the 138 nitrate tests on record for Chambers County (1941–2014),
22% found none, and half were below 1 mg/L.
Of the 412 sulfate tests on record for Chambers County (1935–2014),
1% found none, and half were below 4 mg/L.
Of the 65 uranium tests on record for Chambers County (1994–2021),
66% found none.
Data Coverage & Gaps
Well-sampled analytes (15+ samples)
Chloride 438 samples
Manganese 116 samples
Iron 186 samples
Nitrate 138 samples
Arsenic 109 samples
Sulfate 412 samples
Lead 103 samples
Fluoride 358 samples
Nitrite 19 samples
Uranium 65 samples
Sodium 41 samples
pH 65 samples
Hardness 396 samples
Limited data (<15 samples) — interpret with caution
Radon 8 samples
No private-well PFAS data for Chambers County
We have no private well sampling data for PFAS compounds (PFOA, PFOS, PFNA, and related chemicals) in Chambers 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 →
CDC Health Outcome Correlations
Where contaminants detected in Chambers 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 Chambers 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 Chambers County. Census data explorer →
USGS Aquifer Atlas — principal aquifer type underlying Chambers 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 Chambers County, used in contamination risk scoring. TRI Explorer →
EPA Superfund NPL — National Priorities List sites in or near Chambers 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 TX with at least one sample for that analyte.