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EPA SDWIS ยท Tehama County, California ยท 215 providers profiled

Tehama County, CA Water Quality Report

Tehama County is served by 215 major public water systems on file with the EPA.

Data current as of July 2026
๐Ÿ”Straight from EPA
๐ŸงชReal Lab Results
๐Ÿ“…Updated Quarterly
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Results for Tehama County, CA

215 water providers on file for this county, sorted by population served.

Quick answer: Tehama County has 215 water providers profiled, sorted by population served.

Violations on file

Coliform (TCR)
Older/archived health-based violation
Found at 1 of 215 providers
Lead And Copper Rule Revisions
Currently open health violation
Found at 39 of 215 providers
Surface Water Treatment Rule
Older/archived health-based violation
Found at 1 of 215 providers
Arsenic
Older/archived health-based violation
Found at 1 of 215 providers
Occurs naturally in some groundwater. Long-term exposure above the legal limit (10 ppb) has been linked to increased cancer risk and cardiovascular disease.
Nitrate
Older/archived health-based violation
Found at 1 of 215 providers
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.

Contaminants found

Metals
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0.0306 mg/L (ppm)
Found at 83 providers
Copper, Free
Detected: 475 UG/L (ppb)
Found at 27 providers
Vanadium, Total
Detected: 11 UG/L (ppb)
2/13/2025
Chromium, Hex
Detected: 14.9 UG/L (ppb)
Found at 61 providers
Chromium
Detected: 20 UG/L (ppb)
Found at 7 providers
Occurs in two forms โ€” trivalent (an essential nutrient in trace amounts) and hexavalent (linked to increased cancer risk).
Barium
Detected: 161 UG/L (ppb)
Found at 9 providers
Lead
Detected: 4.28 UG/L (ppb)
Found at 16 providers
A metal that can leach from old pipes, solder, and fixtures. Current medical guidance holds there is no truly safe level of lead exposure, especially for children and pregnant women.
Arsenic
Detected: 8 UG/L (ppb)
Found at 14 providers
Occurs naturally in some groundwater. Long-term exposure above the legal limit (10 ppb) has been linked to increased cancer risk and cardiovascular disease.
Copper Summary
Detected: 2.69 mg/L (ppm)
Found at 2 providers
Combined Uranium
Detected: 1.2 PCI/L
Found at 2 providers
A naturally occurring radioactive metal. Long-term exposure above the legal limit is associated with kidney effects and increased cancer risk.
Iron
Detected: 4430 UG/L (ppb)
Found at 3 providers
Mostly an aesthetic issue (metallic taste, staining) rather than a health concern at typical levels.
Manganese
Detected: 254 UG/L (ppb)
Found at 3 providers
Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.
Nickel
Detected: 0.61 UG/L (ppb)
Found at 2 providers
Aluminum
Detected: 221 UG/L (ppb)
4/15/2025
Zinc
Detected: 15.5 UG/L (ppb)
5/8/2025
Disinfection Byproducts
Formed when chlorine used to disinfect water reacts with organic matter
TTHM
Detected: 47 UG/L (ppb)
Found at 5 providers
A group of disinfection byproducts formed when chlorine reacts with organic matter. Long-term exposure above the legal limit has been linked to increased cancer risk in some studies.
Totalhaloaceticacids (HAA5)
Detected: 25 UG/L (ppb)
Found at 3 providers
Chloroform
Detected: 38 UG/L (ppb)
Found at 6 providers
One of the individual trihalomethane disinfection byproducts, formed when chlorine reacts with organic matter.
Bromodichloromethane
Detected: 13 UG/L (ppb)
Found at 5 providers
Dibromochloromethane
Detected: 7.3 UG/L (ppb)
Found at 5 providers
Bromoform
Detected: 2 UG/L (ppb)
Found at 6 providers
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Nitrate
Detected: 9.46 MG/L (ppm)
Found at 85 providers
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
Chloride
Detected: 18.6 MG/L (ppm)
Found at 5 providers
Sulfate
Detected: 18 MG/L (ppm)
Found at 4 providers
Fluoride
Detected: 0.2 MG/L (ppm)
Found at 6 providers
Often added deliberately for dental health; can also occur naturally.
Nitrate-Nitrite
Detected: 1.1 MG/L (ppm)
Found at 2 providers
Minerals
Everyday minerals that mainly affect taste and water hardness
Magnesium
Detected: 12 MG/L (ppm)
Found at 4 providers
Potassium
Detected: 3 MG/L (ppm)
Found at 2 providers
Sodium
Detected: 33.3 MG/L (ppm)
Found at 3 providers
Calcium
Detected: 30.5 MG/L (ppm)
Found at 4 providers
Properties
General water characteristics like pH, hardness, and cloudiness (turbidity)
pH
Detected: 8.05 PH
Found at 3 providers
A measure of how acidic or basic the water is (7 is neutral). Affects taste and plumbing, not a direct health measure.
Gross Alpha Particle Activity
Detected: 2.98 PCI/L
Found at 6 providers
pH, Field
Detected: 8.14 PH
Found at 2 providers
Langelier Index (pH(s))
Detected: -0.3 LANG
9/17/2025
Hardness, Total (ASCACO3)
Detected: 104 MG/L (ppm)
Found at 4 providers
PFAS & Emerging Contaminants
Human-made "forever chemicals" and other substances not yet fully regulated
Lithium
Detected: 9.48 ยตg/L (ppb)
5/2/2023
Occurs naturally in some groundwater. Not currently federally regulated in drinking water.
PFPEA
Detected: 0.0067 ยตg/L (ppb)
1/11/2024
PFOA
Detected: 0.0074 ยตg/L (ppb)
1/11/2024
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
PFHPA
Detected: 0.0055 ยตg/L (ppb)
1/11/2024
PFHXA
Detected: 0.006 ยตg/L (ppb)
1/11/2024
Calculated Parameters
Values worked out mathematically from other test results, not measured directly
Alkalinity, Bicarbonate
Detected: 120 MG/L (ppm)
Found at 2 providers
Other
Additional substances tested that don't fit neatly into the categories above
Perfluoroheptanoicacid (PFHPA)
Detected: 150 NG/L (ppt)
Found at 14 providers
Perfluorohexanesulfonicacid (PFHxS)
Detected: 3.8 NG/L (ppt)
Found at 8 providers
Perfluorononanoicacid (PFNA)
Detected: 26 NG/L (ppt)
Found at 7 providers
Perfluoroctanesulfonicacid (PFOS)
Detected: 120 NG/L (ppt)
Found at 20 providers
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluoroctanoicacid (PFOA)
Detected: 320 NG/L (ppt)
Found at 20 providers
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluorodecanoicacid (PFDA)
Detected: 21 NG/L (ppt)
Found at 3 providers
Perfluorohexanoicacid (PFHXA)
Detected: 520 NG/L (ppt)
Found at 15 providers
Perfluorobutanoicacid (PFBA)
Detected: 270 NG/L (ppt)
Found at 11 providers
Perfluorooctanesulfonicacid6:2fts
Detected: 3.8 NG/L (ppt)
Found at 2 providers
Perfluorodecanesulfonicacid8:2fts
Detected: 22 NG/L (ppt)
Found at 2 providers
Perfluoropentanoicacid (PFPEA)
Detected: 490 NG/L (ppt)
Found at 12 providers
Dichloroaceticacid
Detected: 17 UG/L (ppb)
Found at 5 providers
Trichloroaceticacid
Detected: 8 UG/L (ppb)
Found at 4 providers
Turbidity
Detected: 19.5 NTU
Found at 4 providers
A measure of water cloudiness from suspended particles.
Radium-228
Detected: 0.58 PCI/L
Found at 4 providers
Radium-226
Detected: 0.678 PCI/L
Found at 2 providers
Dibromoaceticacid
Detected: 3 UG/L (ppb)
Found at 2 providers
Aggressive Index
Detected: 11.8 AGGR
Found at 2 providers
Alkalinity, Total
Detected: 120 MG/L (ppm)
Found at 2 providers
TDS
Detected: 345 MG/L (ppm)
Found at 4 providers
Conductivity (at 25ยฐC)
Detected: 307 UMHO/CM
Found at 4 providers
Perfluorobutanesulfonicacid (PFBS)
Detected: 8 NG/L (ppt)
Found at 11 providers
Adsorbableorganicfluorine
Detected: 3200 NG/L (ppt)
Found at 2 providers
Filtration considerations: General system types, not a specific product recommendation.
Contaminant Whole-House Carbon Under-Sink RO Under-Sink Carbon
Total Trihalomethanes (TTHM)YesYesYes
Haloacetic Acids (HAA5)YesYesYes
ChloroformYesYesYes
Chlorine / TasteYesYesYes
Sediment / TurbidityYesYesYes
TrichloroethyleneYesYesYes
TetrachloroethyleneYesYesYes
cis-1,2-DichloroethyleneYesYesYes
1,1-DichloroethyleneYesYesYes
BromoformYesYesYes
BromodichloromethaneYesYesYes
DibromochloromethaneYesYesYes
1,1,2-TrichloroethaneYesYesYes
Vinyl ChlorideYesYesYes
Carbon TetrachlorideYesYesYes
BenzeneYesYesYes
TolueneYesYesYes
XyleneYesYesYes
Totalhaloaceticacids (HAA5)YesYesYes
LeadPartialYesPartial
ArsenicPartialYesPartial
Chromium-6 (Hexavalent)PartialYesPartial
CopperPartialYesPartial
Combined UraniumPartialYesPartial
PFOAPartialYes*Partial
PFOSPartialYes*Partial
NitratePartialYesPartial
Combined RadiumPartialYesPartial
Copper, FreePartialYesPartial
Vanadium, TotalPartialYesPartial
Chromium, HexPartialYesPartial
ChromiumPartialYesPartial
BariumPartialYesPartial
Perfluoroheptanoicacid (PFHPA)PartialYesPartial
Perfluorohexanesulfonicacid (PFHxS)PartialYesPartial
Perfluorononanoicacid (PFNA)PartialYesPartial
Perfluoroctanesulfonicacid (PFOS)PartialYesPartial
Perfluoroctanoicacid (PFOA)PartialYesPartial
Perfluorodecanoicacid (PFDA)PartialYesPartial
Perfluorohexanoicacid (PFHXA)PartialYesPartial
Perfluorobutanoicacid (PFBA)PartialYesPartial
Perfluorooctanesulfonicacid6:2ftsPartialYesPartial
Perfluorodecanesulfonicacid8:2ftsPartialYesPartial
Perfluoropentanoicacid (PFPEA)PartialYesPartial
DichloroaceticacidPartialYesPartial
TrichloroaceticacidPartialYesPartial
LithiumPartialYes*Partial
Radium-226PartialYesPartial
Combined UraniumPartialYesPartial
DibromoaceticacidPartialYesPartial
PFPEAPartialYes*Partial
PFHPAPartialYes*Partial
PFHXAPartialYes*Partial
Aggressive IndexPartialYesPartial
Alkalinity, TotalPartialYesPartial
TDSPartialYesPartial
ChloridePartialYesPartial
SulfatePartialYesPartial
FluoridePartialYesPartial
Nitrate-NitritePartialYesPartial
Conductivity (at 25ยฐC)PartialYesPartial
Perfluorobutanesulfonicacid (PFBS)PartialYesPartial
IronPartialYesPartial
ManganesePartialYesPartial
NickelPartialYesPartial
AdsorbableorganicfluorinePartialYesPartial
AluminumPartialYesPartial
ZincPartialYesPartial
Coliform Bacteria (indicator)NoYesNo
pHNoNoNo
Gross Alpha Particle ActivityNoNoNo
pH, FieldNoNoNo
Langelier Index (pH(s))NoNoNo
MagnesiumNoPartialNo
PotassiumNoPartialNo
SodiumNoPartialNo
Hardness, Total (ASCACO3)NoNoNo
CalciumNoPartialNo
Alkalinity, BicarbonateNoNoNo

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What is TTHM? Understanding EPA Violation Status Is Chromium-6 Dangerous? Whole-House vs. Under-Sink Filtration Lead and Copper in Drinking Water What is PFAS? Arsenic and Uranium Explained Nitrate and Fluoride Explained Water Hardness, pH, and Turbidity What is Coliform Bacteria?