Serving roughly 8,099 people in Los Angeles County, California.
Data current as of July 2026
🔍Straight from EPA
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Results for GSWC - HOLLYDALE
1 water provider directly on file, serving roughly 8,099 people in Los Angeles County, California.
Quick answer: GSWC - HOLLYDALE has no violations on file. One reading is worth knowing about: Perfluoroctanesulfonicacid (PFOS) was measured at 29NG/L, among the highest of the 601 providers on file in this area. It's the most notable figure in this system's record among its 601 local peers.
Lead Summary
PFBA
TTHM
Bromoform
Bromodichloromethane
Dibromochloromethane
Copper, Free
Perfluorobutanesulfonicacid (PFBS)
Perfluorohexanesulfonicacid (PFHxS)
Perfluoroctanesulfonicacid (PFOS)
Perfluoroctanoicacid (PFOA)
Perfluorobutanoicacid (PFBA)
Manganese
Arsenic
Fluoride
Nitrate
Chromium, Hex
Utility GSWC - HOLLYDALEPopulation served 8,099Owner Private
No violations on file
Contaminants found
Metals
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0 mg/L (ppm)
12/31/2025
Copper, Free
Detected: 85 UG/L (ppb)
9/24/2025
Manganese
Detected: 2.5 UG/L (ppb)
10/28/2025
Mainly a taste/staining concern at typical levels; long-term neurological research at high chronic exposure is ongoing.
Arsenic
Detected: 2 UG/L (ppb)
10/28/2025
Occurs naturally in some groundwater. Long-term exposure above the legal limit (10 ppb) has been linked to increased cancer risk and cardiovascular disease.
Chromium, Hex
Detected: 0.54 UG/L (ppb)
2/12/2025
Disinfection Byproducts
Formed when chlorine used to disinfect water reacts with organic matter
TTHM
Detected: 5.2 UG/L (ppb)
8/5/2025
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.
Bromoform
Detected: 2 UG/L (ppb)
8/5/2025
Bromodichloromethane
Detected: 1 UG/L (ppb)
8/5/2025
Dibromochloromethane
Detected: 2.2 UG/L (ppb)
8/5/2025
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Fluoride
Detected: 0.38 MG/L (ppm)
2/11/2025
Often added deliberately for dental health; can also occur naturally.
Nitrate
Detected: 1.6 MG/L (ppm)
2/11/2025
Commonly from agricultural fertilizer runoff or septic systems. Above the legal limit, it's an immediate concern especially for infants.
PFAS & Emerging Contaminants
Human-made "forever chemicals" and other substances not yet fully regulated
PFBA
Detected: 0.0053 µg/L (ppb)
2/11/2025
Other
Additional substances tested that don't fit neatly into the categories above
Perfluorobutanesulfonicacid (PFBS)
Detected: 2.7 NG/L (ppt)
10/8/2025
Perfluorohexanesulfonicacid (PFHxS)
Detected: 6 NG/L (ppt)
10/8/2025
Perfluoroctanesulfonicacid (PFOS)
Detected: 29 NG/L (ppt)
10/8/2025
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluoroctanoicacid (PFOA)
Detected: 6.3 NG/L (ppt)
10/8/2025
One of two PFAS with an enforceable federal limit (4 ppt) since 2024.
Perfluorobutanoicacid (PFBA)
Detected: 5.5 NG/L (ppt)
10/8/2025
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.