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Tap water quality report

Tamoshan

EPA monitoring tested this supplier for 55 contaminants and detected 11. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

55
contaminants tested
11
detected
260
people served
23
health-based violations
Washington rankingsLead in WashingtonPFAS in Washington
Water source
Ground water
Ownership
Local government
Counties served
Thurston

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.

23
health-based violations
38
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2023-04-01 → 2023-06-30
MCL Health-based Resolved 2023-04-01 → 2023-06-30
MCL Health-based Resolved 2023-01-01 → 2023-03-31
MCL Health-based Resolved 2023-01-01 → 2023-03-31
MCL Health-based Resolved 2022-10-01 → 2022-12-31
MCL Health-based Resolved 2022-10-01 → 2022-12-31
MCL Health-based Resolved 2022-07-01 → 2022-09-30
MCL Health-based Resolved 2022-07-01 → 2022-09-30
MCL Health-based Resolved 2022-04-01 → 2022-06-30
MCL Health-based Resolved 2022-04-01 → 2022-06-30

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 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
Chloroform
127 µg/L
No EPA limit set
 27/28 SYR4 2012–2019
TTHM
132 µg/L 165%
of the EPA limit, in the worst sample — 80 µg/L
 27/27 SYR4 2013–2019
Dichloroacetic Acid
31.2 µg/L
No EPA limit set
 26/28 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
75.6 µg/L 126%
of the EPA limit, in the worst sample — 60 µg/L
 26/28 SYR4 2012–2019
Bromodichloromethane
6.2 µg/L
No EPA limit set
 21/27 SYR4 2012–2019
Trichloroacetic Acid
46.94 µg/L
No EPA limit set
 21/27 SYR4 2012–2019
Lead
0.0066 mg/L 44%
of the EPA limit 0.0150 mg/L
 11/11 LCR 2025
Monochloroacetic Acid
11.1 µg/L
No EPA limit set
 3/28 SYR4 2012–2019
Lead
2 µg/L 13%
of the EPA limit 15 µg/L
 2/3 SYR4 2012–2014
Monobromoacetic Acid
6.1 µg/L
No EPA limit set
 2/28 SYR4 2012–2019
Barium
255 µg/L 13%
of the EPA limit 2000 µg/L
 1/3 SYR4 2012–2014
44 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane2,4,5-TP2,4-DAntimony, TotalArsenicBenzeneBeryllium, TotalBromoformChlorobenzeneCopperCyanideCadmiumCarbon TetrachlorideChromiumDichloromethaneDalaponDibromoacetic AcidDibromochloromethaneDinosebEthylbenzeneFluorideMercuryNitrateNitrate-NitriteNitritePentachlorophenolPicloramSeleniumStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
Kevin Patching

Frequently asked questions about Tamoshan

Is Tamoshan tap water safe to drink?

EPA monitoring detected 11 contaminants in Tamoshan'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 Tamoshan's water?

EPA monitoring detected Chloroform, TTHM, Dichloroacetic Acid, Total Haloacetic Acids (HAA5), Bromodichloromethane, and others. The full list with the level and data source for each is above.

How many people does Tamoshan serve?

Tamoshan reports serving 260 people in Washington, per its EPA record.

Has Tamoshan had any water quality violations?

The EPA has 38 violations on file for Tamoshan, of which 23 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.