EPA SDWIS · Alameda County, California · 50 providers profiled
Alameda County, CA Water Quality Report
Alameda County is served by 50 major public water systems on file with the EPA.
Data current as of July 2026
🔍Straight from EPA
🧪Real Lab Results
📅Updated Quarterly
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Results for Alameda County, CA
50 water providers on file for this county, sorted by population served.
Quick answer: Alameda County has 50 water providers profiled, sorted by population served.
Copper Summary
Lead Summary
Nitrate
Lead
Totalhaloaceticacids (HAA5)
TTHM
Chloroform
Bromoform
Bromodichloromethane
Dibromochloromethane
Dichloroaceticacid
Trichloroaceticacid
Dibromoaceticacid
Monochloroaceticacid
Copper, Free
Fluoride
Nickel
Chromium
Barium
Arsenic
Aluminum
Perfluorobutanesulfonicacid (PFBS)
Perfluorohexanesulfonicacid (PFHxS)
Perfluorobutanoicacid (PFBA)
Perfluoroctanesulfonicacid (PFOS)
Perfluoropentanoicacid (PFPEA)
Perfluoropentanesulfonicacid (PFPES)
Tetrachloroethylene
Aggressive Index
Sodium
TDS
Chloride
Sulfate
Magnesium
Potassium
Calcium
Alkalinity, Total
Alkalinity, Bicarbonate
Hardness, Total (ASCACO3)
Perfluoroctanoicacid (PFOA)
Perfluorohexanoicacid (PFHXA)
Turbidity
Radium-228
Combined Radium (-226 & -228)
Gross Alpha Particle Activity
Gross Beta Particle Activity
pH
Boron, Total
Vanadium, Total
Iron
Manganese
Thallium, Total
Beryllium, Total
Cadmium
Zinc
Conductivity (at 25°C)
Odor
Chromium, Hex
Foamingagents (SURFACTANTS)
Nitrate-Nitrite
Perfluoroheptanoicacid (PFHPA)
PFPEA
PFBS
PFHXA
Lithium
PFHXS
PFOA
PFOS
Monobromoaceticacid
PFBA
Alkalinity, Carbonate
Hydroxideascalciumcarbonate
Pfpes
Temperature (CENTIGRADE)
Bromide
Carbon, Total
Silica
Turbidity, Field
pH, Field
Strontium
Chlorate
Molybdenum, Total
Selenium
Color
Perchlorate
Violations on file
Revised Total Coliform Rule
Older/archived health-based violation
Found at 1 of 50 providers
Coliform (TCR)
Older/archived health-based violation
Found at 2 of 50 providers
Lead And Copper Rule Revisions
Currently open health violation
Found at 3 of 50 providers
Contaminants found
Metals
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Copper Summary
Detected: 2.25 mg/L (ppm)
Found at 6 providers
Lead Summary
Detected: 0.041 mg/L (ppm)
Found at 22 providers
Lead
Detected: 173 UG/L (ppb)
Found at 4 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.
Copper, Free
Detected: 1000 UG/L (ppb)
Found at 5 providers
Nickel
Detected: 1600 UG/L (ppb)
Found at 3 providers
Chromium
Detected: 930 UG/L (ppb)
Found at 4 providers
Occurs in two forms — trivalent (an essential nutrient in trace amounts) and hexavalent (linked to increased cancer risk).
Barium
Detected: 2800 UG/L (ppb)
Found at 4 providers
Arsenic
Detected: 63 UG/L (ppb)
Found at 4 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.
Aluminum
Detected: 155 UG/L (ppb)
Found at 2 providers
Vanadium, Total
Detected: 480 UG/L (ppb)
Found at 2 providers
Iron
Detected: 94000 UG/L (ppb)
Found at 3 providers
Mostly an aesthetic issue (metallic taste, staining) rather than a health concern at typical levels.
Manganese
Detected: 8600 UG/L (ppb)
Found at 2 providers
Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.
Thallium, Total
Detected: 1.1 UG/L (ppb)
9/16/2025
Beryllium, Total
Detected: 5.2 UG/L (ppb)
9/16/2025
Cadmium
Detected: 2.1 UG/L (ppb)
9/16/2025
Zinc
Detected: 850 UG/L (ppb)
9/16/2025
Chromium, Hex
Detected: 5.4 UG/L (ppb)
Found at 4 providers
Strontium
Detected: 171 UG/L (ppb)
2/3/2025
Molybdenum, Total
Detected: 3.1 UG/L (ppb)
1/9/2025
Selenium
Detected: 5.9 UG/L (ppb)
8/18/2025
Disinfection Byproducts
Formed when chlorine used to disinfect water reacts with organic matter
Totalhaloaceticacids (HAA5)
Detected: 72.7 UG/L (ppb)
Found at 9 providers
TTHM
Detected: 73.29 UG/L (ppb)
Found at 10 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.
Chloroform
Detected: 71.86 UG/L (ppb)
Found at 8 providers
One of the individual trihalomethane disinfection byproducts, formed when chlorine reacts with organic matter.
Bromoform
Detected: 35 UG/L (ppb)
Found at 9 providers
Bromodichloromethane
Detected: 14 UG/L (ppb)
Found at 8 providers
Dibromochloromethane
Detected: 26 UG/L (ppb)
Found at 8 providers
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Nitrate
Detected: 6.3 MG/L (ppm)
Found at 12 providers
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
Fluoride
Detected: 0.81 MG/L (ppm)
Found at 8 providers
Often added deliberately for dental health; can also occur naturally.
Chloride
Detected: 112 MG/L (ppm)
Found at 5 providers
Sulfate
Detected: 93.9 MG/L (ppm)
Found at 5 providers
Boron, Total
Detected: 630 UG/L (ppb)
Found at 2 providers
Nitrate-Nitrite
Detected: 2.53 MG/L (ppm)
Found at 2 providers
Minerals
Everyday minerals that mainly affect taste and water hardness
Sodium
Detected: 74 MG/L (ppm)
Found at 4 providers
Magnesium
Detected: 81 MG/L (ppm)
Found at 4 providers
Potassium
Detected: 8.3 MG/L (ppm)
Found at 3 providers
Calcium
Detected: 140 MG/L (ppm)
Found at 4 providers
Hydroxideascalciumcarbonate
Detected: 7.2 MG/L (ppm)
6/24/2025
Properties
General water characteristics like pH, hardness, and cloudiness (turbidity)
Hardness, Total (ASCACO3)
Detected: 679 MG/L (ppm)
Found at 4 providers
Gross Alpha Particle Activity
Detected: 3.15 PCI/L
9/16/2025
pH
Detected: 8.1 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.
pH, Field
Detected: 8.7 PH
2/3/2025
PFAS & Emerging Contaminants
Human-made "forever chemicals" and other substances not yet fully regulated
PFPEA
Detected: 0.0035 µg/L (ppb)
Found at 2 providers
PFBS
Detected: 0.0061 µg/L (ppb)
Found at 2 providers
PFHXA
Detected: 0.0038 µg/L (ppb)
Found at 2 providers
Lithium
Detected: 9.62 µg/L (ppb)
Found at 2 providers
Occurs naturally in some groundwater. Not currently federally regulated in drinking water.
PFHXS
Detected: 0.018 µg/L (ppb)
Found at 2 providers
PFOA
Detected: 0.0048 µg/L (ppb)
Found at 2 providers
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
PFOS
Detected: 0.026 µg/L (ppb)
Found at 2 providers
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
PFBA
Detected: 0.006 µg/L (ppb)
Found at 2 providers
Pfpes
Detected: 0.0043 µg/L (ppb)
8/20/2024
VOCs (Volatile Organic Compounds)
Industrial solvents and fuel-related chemicals that evaporate easily
Tetrachloroethylene
Detected: 1.6 UG/L (ppb)
7/1/2025
Bromide
Detected: 0.06 MG/L (ppm)
2/3/2025
Calculated Parameters
Values worked out mathematically from other test results, not measured directly
Alkalinity, Bicarbonate
Detected: 429 MG/L (ppm)
Found at 5 providers
Alkalinity, Carbonate
Detected: 24 MG/L (ppm)
Found at 2 providers
Other
Additional substances tested that don't fit neatly into the categories above
Dichloroaceticacid
Detected: 40.1 UG/L (ppb)
Found at 9 providers
Trichloroaceticacid
Detected: 29.6 UG/L (ppb)
Found at 8 providers
Dibromoaceticacid
Detected: 13.8 UG/L (ppb)
Found at 8 providers
Monochloroaceticacid
Detected: 3 UG/L (ppb)
Found at 5 providers
Perfluorobutanesulfonicacid (PFBS)
Detected: 6.7 NG/L (ppt)
Found at 2 providers
Perfluorohexanesulfonicacid (PFHxS)
Detected: 6 NG/L (ppt)
Found at 3 providers
Perfluorobutanoicacid (PFBA)
Detected: 3.9 NG/L (ppt)
Found at 3 providers
Perfluoroctanesulfonicacid (PFOS)
Detected: 4.2 NG/L (ppt)
Found at 2 providers
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluoropentanoicacid (PFPEA)
Detected: 2.1 NG/L (ppt)
Found at 2 providers
Perfluoropentanesulfonicacid (PFPES)
Detected: 1.8 NG/L (ppt)
10/8/2025
Aggressive Index
Detected: 12.84 AGGR
Found at 2 providers
TDS
Detected: 756 MG/L (ppm)
Found at 5 providers
Alkalinity, Total
Detected: 441 MG/L (ppm)
Found at 5 providers
Perfluoroctanoicacid (PFOA)
Detected: 2.2 NG/L (ppt)
Found at 2 providers
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluorohexanoicacid (PFHXA)
Detected: 2.3 NG/L (ppt)
Found at 2 providers
Turbidity
Detected: 5600 NTU
Found at 4 providers
A measure of water cloudiness from suspended particles.
Radium-228
Detected: 0.958 PCI/L
Found at 2 providers
Combined Radium (-226 & -228)
Detected: 1.01 PCI/L
9/16/2025
A naturally occurring radioactive element found in some groundwater.
Gross Beta Particle Activity
Detected: 3.29 PCI/L
9/16/2025
Conductivity (at 25°C)
Detected: 1320 UMHO/CM
Found at 4 providers
Odor
Detected: 1.4 TON
Found at 2 providers
Foamingagents (SURFACTANTS)
Detected: 0.12 MG/L (ppm)
9/15/2025
Perfluoroheptanoicacid (PFHPA)
Detected: 2.1 NG/L (ppt)
7/21/2025
Monobromoaceticacid
Detected: 1.52 UG/L (ppb)
Found at 3 providers
Temperature (CENTIGRADE)
Detected: 12.9 C
2/3/2025
Carbon, Total
Detected: 2.72 MG/L (ppm)
2/3/2025
Silica
Detected: 28 MG/L (ppm)
8/19/2025
Turbidity, Field
Detected: 4.3 NTU
2/3/2025
Chlorate
Detected: 67 UG/L (ppb)
Found at 2 providers
Color
Detected: 25 UNITS
1/6/2025
Perchlorate
Detected: 1 UG/L (ppb)
9/10/2025
Can occur naturally or from industrial/military sources; may interfere with thyroid function at elevated levels.
Filtration considerations: General system types, not a specific product recommendation.