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Tap water quality report

Yak Co - Terrace Heights

EPA monitoring tested this supplier for 103 contaminants and detected 22. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

103
contaminants tested
22
detected
8,410
people served
2
health-based violations
Washington rankingsLead in WashingtonPFAS in Washington
Water source
Ground water
Ownership
Local government
Counties served
Yakima

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.

2
health-based violations
194
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2023-08-01 → 2023-08-31
MCL Health-based Archived 1993-07-01 → 1993-07-31
MR Monitoring Resolved 2025-01-01 → 2025-12-31
MR Monitoring Resolved 2025-01-01 → 2025-12-31
MR Monitoring Resolved 2025-01-01 → 2025-12-31
MON Monitoring Resolved 2022-10-01 → 2022-10-31
MR Monitoring Resolved 2020-01-01 → 2025-12-31
MR Monitoring Resolved 2020-01-01 → 2025-12-31
MR Monitoring Resolved 2020-01-01 → 2025-12-31
MR Monitoring Resolved 2020-01-01 → 2025-12-31

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
2550 µg/L 26%
of the EPA limit 10000 µg/L
 54/72 SYR4 2012–2019
Nitrate-Nitrite
2550 µg/L 26%
of the EPA limit 10000 µg/L
 27/36 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 11/11 LCR 2023
Bromoform
8.9 µg/L
No EPA limit set
 8/17 SYR4 2013–2019
Chloroform
9 µg/L
No EPA limit set
 8/17 SYR4 2013–2019
Dibromochloromethane
5.7 µg/L
No EPA limit set
 8/17 SYR4 2013–2019
TTHM
19.9 µg/L 25%
of the EPA limit 80 µg/L
 8/8 SYR4 2013–2019
Bromodichloromethane
6.2 µg/L
No EPA limit set
 7/17 SYR4 2013–2019
Arsenic
4.79 µg/L 48%
of the EPA limit 10 µg/L
 5/5 SYR4 2016–2019
Barium
76.14 µg/L 3.8%
of the EPA limit 2000 µg/L
 5/5 SYR4 2016–2019
Copper
3.99 µg/L 0.3%
of the EPA limit 1300 µg/L
 5/5 SYR4 2016–2019
Fluoride
790 µg/L 20%
of the EPA limit 4000 µg/L
 5/5 SYR4 2016–2019
Thallium, Total
0.7200 µg/L 36%
of the EPA limit 2 µg/L
 5/5 SYR4 2016–2019
Chromium
2.79 µg/L 2.8%
of the EPA limit 100 µg/L
 4/5 SYR4 2016–2019
Lead
2.48 µg/L 17%
of the EPA limit 15 µg/L
 3/5 SYR4 2016–2019
Selenium
1.08 µg/L 2.2%
of the EPA limit 50 µg/L
 3/5 SYR4 2016–2019
Antimony, Total
0.1300 µg/L 2.2%
of the EPA limit 6 µg/L
 2/5 SYR4 2016–2019
Total Haloacetic Acids (HAA5)
5.6 µg/L 9.3%
of the EPA limit 60 µg/L
 2/9 SYR4 2013–2018
Lithium
12.9 µg/L
No EPA limit set
 2/10 UCMR-5 2025
Dibromoacetic Acid
1.3 µg/L
No EPA limit set
 1/10 SYR4 2013–2019
Dichloroacetic Acid
3.8 µg/L
No EPA limit set
 1/10 SYR4 2013–2019
Trichloroacetic Acid
1.8 µg/L
No EPA limit set
 1/10 SYR4 2013–2019
81 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbon TetrachlorideChlordaneDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebEthylene DibromideEndrinEthylbenzeneHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNetfosaaNfdhaNmefosaaNitritePfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
Gene Buermann

Frequently asked questions about Yak Co - Terrace Heights

Is Yak Co - Terrace Heights tap water safe to drink?

EPA monitoring detected 22 contaminants in Yak Co - Terrace Heights'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 Yak Co - Terrace Heights's water?

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

How many people does Yak Co - Terrace Heights serve?

Yak Co - Terrace Heights reports serving 8,410 people in Washington, per its EPA record.

Has Yak Co - Terrace Heights had any water quality violations?

The EPA has 194 violations on file for Yak Co - Terrace Heights, 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.