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Tap water quality report

Laguna Negra Mutual Water Co.

EPA monitoring tested this supplier for 52 contaminants and detected 11. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

52
contaminants tested
11
detected
80
people served
0
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
Ground water
Ownership
Private
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.

0
health-based violations
16
violations on file
0
still open
ViolationTypeStatusPeriod
MR Monitoring Resolved 2023-01-01 → 2023-12-31
MR Monitoring Resolved 2023-01-01 → 2023-12-31
MR Monitoring Resolved 2021-10-01
MR Monitoring Resolved 2021-10-01
MR Monitoring Resolved 2017-10-01
MR Monitoring Resolved 2017-10-01
MR Monitoring Resolved 2017-01-01 → 2017-12-31
MR Monitoring Resolved 2017-01-01 → 2017-12-31
MR Monitoring Resolved 2006-01-01 → 2006-01-31
MR Monitoring Resolved 2006-01-01 → 2006-01-31

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 single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
7100 µg/L 71%
of the EPA limit 10000 µg/L
 26/26 SYR4 2013–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 3/3 LCR 2025
Copper
10 µg/L 0.8%
of the EPA limit 1300 µg/L
 2/6 SYR4 2013–2019
Nitrate-Nitrite
7000 µg/L 70%
of the EPA limit 10000 µg/L
 2/2 SYR4 2019
Barium
29.8 µg/L 1.5%
of the EPA limit 2000 µg/L
 1/5 SYR4 2013–2019
Bromoform
2 µg/L
No EPA limit set
 1/1 SYR4 2019
Cadmium
0.5000 µg/L 10%
of the EPA limit 5 µg/L
 1/5 SYR4 2013–2019
Dibromochloromethane
1 µg/L
No EPA limit set
 1/1 SYR4 2019
Lead
0.4000 µg/L 2.7%
of the EPA limit 15 µg/L
 1/5 SYR4 2013–2019
Selenium
4 µg/L 8%
of the EPA limit 50 µg/L
 1/5 SYR4 2013–2019
TTHM
3 µg/L 3.8%
of the EPA limit 80 µg/L
 1/1 SYR4 2019
41 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-DichloropropaneAntimony, TotalArsenicAtrazineBenzeneBeryllium, TotalBromodichloromethaneChlorobenzeneCyanideCarbon TetrachlorideChloroformChromiumDichloromethaneDibromoacetic AcidDichloroacetic AcidEthylbenzeneFluorideLassoMercuryMonobromoacetic AcidMonochloroacetic AcidNitriteSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Haloacetic Acids (HAA5)Trichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
WILSON, STEPHEN
Phone
805-980-1600
Email
STEVEWILSON1@JUNO.COM

Frequently asked questions about Laguna Negra Mutual Water Co.

Is Laguna Negra Mutual Water Co. tap water safe to drink?

EPA monitoring detected 11 contaminants in Laguna Negra Mutual Water Co.'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 Laguna Negra Mutual Water Co.'s water?

EPA monitoring detected Nitrate, Lead, Copper, Nitrate-Nitrite, Barium, and others. The full list with the level and data source for each is above.

How many people does Laguna Negra Mutual Water Co. serve?

Laguna Negra Mutual Water Co. reports serving 80 people in California, per its EPA record.

Has Laguna Negra Mutual Water Co. had any water quality violations?

The EPA has 16 violations on file for Laguna Negra Mutual Water Co., of which 0 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.