- EPA's UCMR 5 testing looked for 30 contaminants here and found 5.
- Lithium: found in 6 of 7 samples, average 21.7 µg/L, highest 35.2 µg/L (EPA UCMR 5 testing, Jan 2024–Oct 2024)
- PFBA (a PFAS): found in 3 of 7 samples, average 2.8 ppt, highest 8.7 ppt (EPA UCMR 5 testing, Jan 2024–Oct 2024)
- PFPeA (a PFAS): found in 3 of 7 samples, average 1.9 ppt, highest 5.7 ppt (EPA UCMR 5 testing, Jan 2024–Oct 2024)
- PFHxA (a PFAS): found in 2 of 7 samples, average 1.2 ppt, highest 5.1 ppt (EPA UCMR 5 testing, Jan 2024–Oct 2024)
- PFBS (a PFAS): found in 2 of 7 samples, average 1.2 ppt, highest 5 ppt (EPA UCMR 5 testing, Jan 2024–Oct 2024)
- Lead: 9 in 10 homes tested came in at or below 3 ppb, at or below EPA's 15 ppb action level (latest EPA result for a testing period that ran on or after July 1, 2021: Jan 1, 2026–Jun 30, 2026). This is one number for the whole water system, from homes the utility tested. It isn't a result for your home.
Public EPA test results
Highlands Ranch, CO tap water: what EPA records show
EPA system ID CO0118015 · serves Douglas County, CO · about 103,444 people (EPA records)
Here's what EPA has on file for this water system: its testing for newer contaminants like PFAS (UCMR 5), lead testing and violations. It's not a test of your tap, and there's no Water Score here.
Public EPA test results
Highlands Ranch WSD (EPA CO0118015)
EPA data as of October 14, 2026. For Highlands Ranch's main utility, Highlands Ranch WSD: We found no health-standard violations in EPA's records for this system (CO0118015) since July 1, 2021, as of October 14, 2026. PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
What EPA records show for Highlands Ranch WSD, as of October 14, 2026
We found no health-standard violations in EPA's records for this system (CO0118015) since July 1, 2021, as of October 14, 2026.
Source: EPA ECHO record for Highlands Ranch WSD (SDWIS). Data as of October 14, 2026.
Lead: 9 in 10 homes tested came in at or below 3 ppb, at or below EPA's 15 ppb action level (latest EPA result for a testing period that ran on or after July 1, 2021: Jan 1, 2026–Jun 30, 2026). This is one number for the whole water system, from homes the utility tested. It isn't a result for your home.
EPA's UCMR 5 testing looked for 30 contaminants here and found 5.
PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
Source: EPA records (SDWIS, UCMR 5). SDWIS: data as of Oct 14, 2026. EPA UCMR 5 data, samples through June 2026.
Your water bill names your utility.
Does Highlands Ranch WSD use chloramine?
We didn't find chloramine in Highlands Ranch WSD's EPA treatment records. That's not a complete list; your utility's annual water quality report says which disinfectant it uses.