Hamilton Creek MD

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: 200 people
Connections: 104
Water source: Surface water
Based in: Dillon, CO
County: Summit
Owner: Local government

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. No health-based violations on file since 2016.

What was found

Total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, arsenic, chromium (total), nitrate and uranium: Colorado’s own results, samples taken from Aug. 13, 2020 to Aug. 17, 2026, with EPA’s 2012 to 2019 file for earlier years.

Below EPA’s limits3

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

38.5ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 38.5 ppb, in 2026, below EPA’s legal limit of 80 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 52.2 ppb, in 2012.

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

27ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 27 ppb, in 2026, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 56.4 ppb, in 2012.

What handles it

No certification claim covers this compound yet.

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.26ppm

Highest yearly average, 2020 to 2022

Averaged by year, the highest was 0.26 ppm, in 2022, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.24 ppm, in 2012.

What handles it

NSF/ANSI 58 look for “Fluoride Reduction”
NSF/ANSI 53 look for “Fluoride”

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

Arsenic
Chromium (total)
Lead
Nitrate
Uranium

Violations since 2016

No health-based violations on file with EPA since 2016. There are 5 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, arsenic, chromium (total), nitrate and uranium results here are Colorado’s own from 2020 on, with EPA’s national file for 2012 to 2019. Hamilton Creek MD’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. 13, 2020 to Aug. 17, 2026.

Testing your own tap

Hamilton Creek MD’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.

No lab Colorado certifies is within 75 miles of the area Hamilton Creek MD serves on the state’s list. Some take samples by mail; the state’s page lists them all.

All 54 certified labs for Colorado