Serving roughly 7,522 people in Sonoma County, California.
Data current as of July 2026
🔍Straight from EPA
🧪Real Lab Results
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Results for SEBASTOPOL, CITY OF
1 water provider directly on file, serving roughly 7,522 people in Sonoma County, California.
Quick answer: SEBASTOPOL, CITY OF has no violations on file and no single reading stands out against its peers (756 other providers in this area). It serves roughly 7,522 people, and the full breakdown below reflects everything EPA and California have on record for it.
Lead Summary
Lithium
TTHM
Bromoform
Dibromochloromethane
Dibromoaceticacid
Silica
Arsenic
Nitrate
Perfluorohexanesulfonicacid (PFHxS)
Perfluorohexanoicacid (PFHXA)
Perfluoropentanoicacid (PFPEA)
Tetrachloroethylene
Utility SEBASTOPOL, CITY OFPopulation served 7,522Owner Local government
Naturally occurring or corrosion-related elements, e.g. lead, arsenic, copper
Lead Summary
Detected: 0 mg/L (ppm)
12/31/2024
Arsenic
Detected: 4.6 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.
Disinfection Byproducts
Formed when chlorine used to disinfect water reacts with organic matter
TTHM
Detected: 1 UG/L (ppb)
8/12/2025
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: 1 UG/L (ppb)
8/12/2025
Dibromochloromethane
Detected: 2.2 UG/L (ppb)
8/12/2025
Inorganics
Common dissolved minerals and salts, e.g. nitrate, fluoride, chloride
Nitrate
Detected: 2 MG/L (ppm)
2/4/2025
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
Lithium
Detected: 9 µg/L (ppb)
3/11/2025
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
Tetrachloroethylene
Detected: 2.3 UG/L (ppb)
9/2/2025
Other
Additional substances tested that don't fit neatly into the categories above
Dibromoaceticacid
Detected: 1 UG/L (ppb)
8/12/2025
Silica
Detected: 38 MG/L (ppm)
9/2/2025
Perfluorohexanesulfonicacid (PFHxS)
Detected: 4.4 NG/L (ppt)
10/8/2025
Perfluorohexanoicacid (PFHXA)
Detected: 2.2 NG/L (ppt)
10/8/2025
Perfluoropentanoicacid (PFPEA)
Detected: 2.5 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.