Compliance record
PFAS detected
PFAS are industrial “forever chemicals”. These are the EPA's latest
nationwide test results (2023–2025).
Other contaminants detected
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of this
system's samples — over 100% is worth reading, but is not by itself a
violation. Where a single sample came in higher than that percentile, it
is noted under the bar. Formal violations are listed separately.
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Combined Uranium | 178.8 µg/L 596% of the EPA limit, at the 95th percentile of samples — 30 µg/L
worst single sample: 223.5 µg/L | 417/1153 | SYR4 | 2012–2019 |
| Bromodichloromethane | 17.26 µg/L No EPA limit set
worst single sample: 21.3 µg/L | 155/155 | SYR4 | 2012–2019 |
| Chloroform | 46.07 µg/L No EPA limit set
worst single sample: 58.1 µg/L | 155/155 | SYR4 | 2012–2019 |
| Dibromochloromethane | 15.08 µg/L No EPA limit set
worst single sample: 29.6 µg/L | 155/155 | SYR4 | 2012–2019 |
| TTHM | 75.59 µg/L 94% of the EPA limit 80 µg/L
worst single sample: 97.6 µg/L | 155/155 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 31.29 µg/L 52% of the EPA limit 60 µg/L
worst single sample: 41 µg/L | 152/152 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 17.2 µg/L No EPA limit set
worst single sample: 27.8 µg/L | 151/152 | SYR4 | 2012–2019 |
| Trichloroacetic Acid | 13.075 µg/L No EPA limit set
worst single sample: 16.7 µg/L | 146/152 | SYR4 | 2012–2019 |
| Bromoform | 27.015 µg/L No EPA limit set
worst single sample: 53.1 µg/L | 54/109 | SYR4 | 2012–2019 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L | 44/44 | LCR | 2023 |
| Dibromoacetic Acid | 7.955 µg/L No EPA limit set
worst single sample: 9.6 µg/L | 42/105 | SYR4 | 2012–2019 |
| Fluoride | 220 µg/L 5.5% of the EPA limit 4000 µg/L
worst single sample: 230 µg/L | 29/84 | SYR4 | 2012–2019 |
| Monochloroacetic Acid | 3.1 µg/L No EPA limit set | 18/98 | SYR4 | 2012–2019 |
| Nitrate | 700 µg/L 7% of the EPA limit 10000 µg/L | 16/168 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 689.5 µg/L 6.9% of the EPA limit 10000 µg/L
worst single sample: 700 µg/L | 8/83 | SYR4 | 2012–2019 |
| Monobromoacetic Acid | 1.1 µg/L No EPA limit set | 4/96 | SYR4 | 2013–2019 |
| Arsenic | 5.3 µg/L 53% of the EPA limit 10 µg/L | 1/84 | SYR4 | 2012–2019 |
| Ethylbenzene | 2.5 µg/L 0.4% of the EPA limit 700 µg/L | 1/37 | SYR4 | 2012–2019 |
| Xylenes, Total | 16 µg/L 0.2% of the EPA limit 10000 µg/L | 1/37 | SYR4 | 2012–2019 |
84 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,3,7,8-TCDD2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAsbestosAtrazineBhc-GammaBariumBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCopperCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMethoxychlorNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdoaPfeesaPfhpsPfmbaPfmpaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl Chloridecis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene
Utility contact
Frequently asked questions about Lake Arrowhead Csd
Is Lake Arrowhead Csd tap water safe to drink?
EPA monitoring detected 27 contaminants in Lake Arrowhead Csd's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.
What contaminants were detected in Lake Arrowhead Csd's water?
EPA monitoring detected Combined Uranium, Bromodichloromethane, Chloroform, Dibromochloromethane, TTHM, and others. The full list with the level and data source for each is above.
How many people does Lake Arrowhead Csd serve?
Lake Arrowhead Csd reports serving 7,038 people in California, per its EPA record.
Has Lake Arrowhead Csd had any water quality violations?
The EPA has no formal drinking-water violations on file for Lake Arrowhead Csd.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.