Serving roughly 90,911 people in Orange County, California.
Data current as of July 2026
🔍Straight from EPA
🧪Real Lab Results
📅Updated Quarterly
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Results for CITY OF WESTMINSTER
1 water provider directly on file, serving roughly 90,911 people in Orange County, California.
Quick answer: CITY OF WESTMINSTER has no violations on file. One reading is worth knowing about: Alkalinity, Bicarbonate was measured at 252MG/L, among the highest of the 167 providers on file in this area. It's the most notable figure in this system's record among its 167 local peers.
Lead Summary
PFHXS
PFOS
Lithium
Calcium
Magnesium
Potassium
Sodium
Hardness, Total (ASCACO3)
Bromide
Chloride
Sulfate
Alkalinity, Bicarbonate
Alkalinity, Total
TDS
Carbon, Total
Fluoride
Nitrate-Nitrite
Nitrate
Perfluorohexanesulfonicacid (PFHxS)
Perfluoroctanesulfonicacid (PFOS)
Perfluoroctanoicacid (PFOA)
Combined Uranium
Gross Alpha Particle Activity
pH
Vanadium, Total
Iron
Manganese
Boron, Total
Chromium, Hex
Perchlorate
Nickel
Chromium
Barium
Arsenic
Selenium
Copper, Free
Conductivity (at 25°C)
Utility CITY OF WESTMINSTERPopulation served 90,911Owner Local government
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0.0047 mg/L (ppm)
12/31/2024
Combined Uranium
Detected: 6.64 PCI/L
7/23/2025
A naturally occurring radioactive metal. Long-term exposure above the legal limit is associated with kidney effects and increased cancer risk.
Vanadium, Total
Detected: 2.8 UG/L (ppb)
8/27/2025
Iron
Detected: 8.7 UG/L (ppb)
8/27/2025
Mostly an aesthetic issue (metallic taste, staining) rather than a health concern at typical levels.
Manganese
Detected: 5.6 UG/L (ppb)
8/27/2025
Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.
Chromium, Hex
Detected: 0.12 UG/L (ppb)
6/5/2025
Nickel
Detected: 4.3 UG/L (ppb)
8/27/2025
Chromium
Detected: 1.7 UG/L (ppb)
7/23/2025
Occurs in two forms — trivalent (an essential nutrient in trace amounts) and hexavalent (linked to increased cancer risk).
Barium
Detected: 95 UG/L (ppb)
8/27/2025
Arsenic
Detected: 1.6 UG/L (ppb)
8/27/2025
Occurs naturally in some groundwater. Long-term exposure above the legal limit (10 ppb) has been linked to increased cancer risk and cardiovascular disease.
Selenium
Detected: 2.4 UG/L (ppb)
8/27/2025
Copper, Free
Detected: 1 UG/L (ppb)
8/27/2025
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Chloride
Detected: 71.7 MG/L (ppm)
8/27/2025
Sulfate
Detected: 141 MG/L (ppm)
8/27/2025
Fluoride
Detected: 0.39 MG/L (ppm)
8/27/2025
Often added deliberately for dental health; can also occur naturally.
Nitrate-Nitrite
Detected: 2.29 MG/L (ppm)
8/27/2025
Nitrate
Detected: 2.29 MG/L (ppm)
8/27/2025
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
Boron, Total
Detected: 100 UG/L (ppb)
7/22/2025
Minerals
Everyday minerals that mainly affect taste and water hardness
Calcium
Detected: 112 MG/L (ppm)
8/27/2025
Magnesium
Detected: 19.5 MG/L (ppm)
8/27/2025
Potassium
Detected: 4 MG/L (ppm)
8/27/2025
Sodium
Detected: 49.8 MG/L (ppm)
8/27/2025
Properties
General water characteristics like pH, hardness, and cloudiness (turbidity)
Hardness, Total (ASCACO3)
Detected: 359 MG/L (ppm)
8/27/2025
Gross Alpha Particle Activity
Detected: 2.51 PCI/L
7/23/2025
pH
Detected: 7.9 PH
8/27/2025
A measure of how acidic or basic the water is (7 is neutral). Affects taste and plumbing, not a direct health measure.
PFAS & Emerging Contaminants
Human-made "forever chemicals" and other substances not yet fully regulated
PFHXS
Detected: 0.005 µg/L (ppb)
9/25/2024
PFOS
Detected: 0.0053 µg/L (ppb)
9/25/2024
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Lithium
Detected: 9.2098 µg/L (ppb)
3/25/2024
Occurs naturally in some groundwater. Not currently federally regulated in drinking water.
VOCs (Volatile Organic Compounds)
Industrial solvents and fuel-related chemicals that evaporate easily
Bromide
Detected: 0.21 MG/L (ppm)
8/27/2025
Calculated Parameters
Values worked out mathematically from other test results, not measured directly
Alkalinity, Bicarbonate
Detected: 252 MG/L (ppm)
8/27/2025
Other
Additional substances tested that don't fit neatly into the categories above
Alkalinity, Total
Detected: 206 MG/L (ppm)
8/27/2025
TDS
Detected: 556 MG/L (ppm)
8/27/2025
Carbon, Total
Detected: 0.18 MG/L (ppm)
8/27/2025
Perfluorohexanesulfonicacid (PFHxS)
Detected: 5.3 NG/L (ppt)
7/22/2025
Perfluoroctanesulfonicacid (PFOS)
Detected: 5.6 NG/L (ppt)
7/22/2025
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluoroctanoicacid (PFOA)
Detected: 3.8 NG/L (ppt)
7/22/2025
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perchlorate
Detected: 1.9 UG/L (ppb)
10/9/2025
Can occur naturally or from industrial/military sources; may interfere with thyroid function at elevated levels.
Conductivity (at 25°C)
Detected: 867 UMHO/CM
8/27/2025
Filtration considerations: See the table below for how whole-house carbon, under-sink reverse osmosis, and under-sink carbon systems compare against what's actually on file here. These are general system types, not a specific product recommendation.