Hidden Valley HOA Water Company

What EPA’s and Colorado’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves: 120 people
Connections: 52
Water source: Surface water bought from another system
Based in: Paonia, CO
County: Delta
Owner: Private

The ZIP code it serves

81428

The short answer

Nothing in EPA’s and Colorado’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. 1 health-based violation since 2016.

What was found

Total trihalomethanes (TTHM) and haloacetic acids (HAA5): Colorado’s own results, samples taken from Aug. 23, 2021 to Aug. 26, 2026, with EPA’s 2012 to 2019 file for earlier years.

Below EPA’s limits2

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

15.5ppb

Highest yearly average, 2021 to 2026

2026, one sample: 12.6 ppb

Averaged by year, the highest was 15.5 ppb, in 2024, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 12.6 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 11.7 ppb, in 2018.

What handles it

NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

9.6ppb

Highest yearly average, 2021 to 2026

2026, one sample: 6.7 ppb

Averaged by year, the highest was 9.6 ppb, in 2024, below EPA’s legal limit of 60 ppb. In 2026, the latest year on file, its one sample was 6.7 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 4.8 ppb, in 2018.

What handles it

No certification claim covers this compound yet.

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.

Lead

Violations since 2016

Contaminant or rule	Type	Period	Measured	Status
Stage 1 Disinfectants and Disinfection Byproducts Rule	Treatment was not run by a certified operator as required.EPA: Treatment Technique No Certif. Operator	July 9, 2024	—	Resolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 25 monitoring or reporting violations not shown.

What this report can’t tell you

Everything else. Total trihalomethanes (TTHM) and haloacetic acids (HAA5) results here are Colorado’s own from 2021 on, with EPA’s national file for 2012 to 2019. Hidden Valley HOA Water Company’s own annual report, which it must send you every year, has the contaminants this page does not show.
Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.
What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.
Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Colorado’s results run from Aug. 23, 2021 to Aug. 26, 2026.

Testing your own tap

Hidden Valley HOA Water Company’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Colorado certifies.

The 2 labs Colorado certifies closest to the area Hidden Valley HOA Water Company serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

Mesa County Public Health Regional Laboratory
Grand Junction, CO · about 48 miles
Certified for bacteria
Eagle River W / S District
Avon, CO · about 73 miles
Certified for bacteria, lead and copper, metals, radioactivity