Is San Luis Obispo Water Department Tap Water Safe? Quality Report

Water source: Surface water
Ownership: Local government
Counties served: San Luis Obispo

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

health-based violations

violations on file

still open

Violation	Type	Status	Period
MCL	Health-based	Resolved	2015-04-01 → 2015-06-30
MCL	Health-based	Resolved	2015-04-01 → 2015-06-30

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
Fluoride	800 µg/L 20% of the EPA limit 4000 µg/L worst single sample: 1000 µg/L	120/123	SYR4	2012–2019
Bromodichloromethane	22.86 µg/L No EPA limit set worst single sample: 29.5 µg/L	117/117	SYR4	2012–2019
Chloroform	59.3 µg/L No EPA limit set worst single sample: 105 µg/L	117/117	SYR4	2012–2019
TTHM	91.8 µg/L 115% of the EPA limit, at the 95th percentile of samples — 80 µg/L worst single sample: 117 µg/L	117/117	SYR4	2012–2019
Dibromochloromethane	16.875 µg/L No EPA limit set worst single sample: 20.9 µg/L	116/117	SYR4	2012–2019
Trichloroacetic Acid	19.7 µg/L No EPA limit set worst single sample: 55 µg/L	107/108	SYR4	2013–2019
Dichloroacetic Acid	16.6 µg/L No EPA limit set worst single sample: 34 µg/L	95/108	SYR4	2013–2019
Dibromoacetic Acid	4 µg/L No EPA limit set worst single sample: 7 µg/L	81/108	SYR4	2013–2019
Bromoform	3.815 µg/L No EPA limit set worst single sample: 9 µg/L	78/117	SYR4	2012–2019
Nitrate	4300 µg/L 43% of the EPA limit 10000 µg/L worst single sample: 5400 µg/L	54/92	SYR4	2012–2019
Total Haloacetic Acids (HAA5)	43.85 µg/L 73% of the EPA limit 60 µg/L worst single sample: 76 µg/L	44/44	SYR4	2017–2019
Lead	0.0 mg/L 0% of the EPA limit 0.0150 mg/L	43/43	LCR	2025
Monobromoacetic Acid	2 µg/L No EPA limit set	36/108	SYR4	2013–2019
Barium	159.3 µg/L 8% of the EPA limit 2000 µg/L worst single sample: 167 µg/L	15/27	SYR4	2012–2019
Arsenic	3.55 µg/L 36% of the EPA limit 10 µg/L worst single sample: 4 µg/L	10/27	SYR4	2012–2019
Chromium	15.1 µg/L 15% of the EPA limit 100 µg/L worst single sample: 16 µg/L	10/27	SYR4	2012–2019
Monochloroacetic Acid	2.6 µg/L No EPA limit set worst single sample: 3 µg/L	9/108	SYR4	2013–2019
Nitrate-Nitrite	200000 µg/L 2000% of the EPA limit, at the 95th percentile of samples — 10000 µg/L	9/26	SYR4	2012–2019
Selenium	3 µg/L 6% of the EPA limit 50 µg/L	7/27	SYR4	2012–2019
Lead	7.185 µg/L 48% of the EPA limit 15 µg/L worst single sample: 7.3 µg/L	2/27	SYR4	2012–2019
Bromate	8.4 µg/L 84% of the EPA limit 10 µg/L	1/97	SYR4	2012–2019
Lithium	10 µg/L No EPA limit set	1/4	UCMR-5	2024

61 contaminants tested, none detected

1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAsbestosAtrazineBenzeneBeryllium, TotalChlorobenzeneCopperCyanideCadmiumCarbon TetrachlorideDichloromethaneEthylbenzeneHfpo-DaMercuryNetfosaaNfdhaNmefosaaNitritePfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact: BOERMAN, MYCHAL
Phone: 805-781-7237
Email: mboerman@slocity.org

Frequently asked questions about San Luis Obispo Water Department

Is San Luis Obispo Water Department tap water safe to drink?

EPA monitoring detected 22 contaminants in San Luis Obispo Water Department'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 San Luis Obispo Water Department's water?

EPA monitoring detected Fluoride, Bromodichloromethane, Chloroform, TTHM, Dibromochloromethane, and others. The full list with the level and data source for each is above.

How many people does San Luis Obispo Water Department serve?

San Luis Obispo Water Department reports serving 47,788 people in California, per its EPA record.

Has San Luis Obispo Water Department had any water quality violations?

The EPA has 2 violations on file for San Luis Obispo Water Department, of which 2 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

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.