Tap Water Quality Report
Tap water quality in HIGHLANDS RANCH, Colorado
Tap water in HIGHLANDS RANCH, Colorado receives a grade of D (66/100) from TapWaterSafety.org. It's served by HIGHLANDS RANCH WSD. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Arsenic significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in HIGHLANDS RANCH's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving HIGHLANDS RANCH.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 26.8 ppb, 446x above the EWG health guideline of 0.06 ppb.
Arsenic significantly above health guideline
Moderate concernArsenic detected at 1.6 ppb, 400x above the EWG health guideline of 0.004 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 28.4 ppb, 190x above the EWG health guideline of 0.15 ppb.
EPA compliance record
Official U.S. EPA records for HIGHLANDS RANCH WSD (system ID CO0118015) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for HIGHLANDS RANCH
Filters matched to the specific contaminants in HIGHLANDS RANCH's water supply.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in HIGHLANDS RANCH's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
26.8 ppb | 0.06 | — | — | — | — | — | 446× over |
| Arsenic Heavy metal |
1.6 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 400× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
28.4 ppb | 0.15 | 80.0 | 100 | — | — | — | 190× over |
| Bromodichloromethane Disinfection byproduct |
9.51 ppb | 0.06 | — | — | — | — | — | 159× over |
| Dibromochloromethane Disinfection byproduct |
10.5 ppb | 0.1 | — | — | — | — | — | 105× over |
| Dibromoacetic acid Disinfection byproduct |
3.11 ppb | 0.03 | — | — | — | — | — | 104× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
9.42 ppb | 0.1 | 60.0 | 60 | — | — | — | 94× over |
| Radium, combined (-226 and -228) Radiological |
1.79 pCi/L | 0.05 | 5.0 | — | — | — | — | 36× over |
| Trichloroacetic acid Disinfection byproduct |
2.16 ppb | 0.1 | — | — | — | — | — | 22× over |
| Dichloroacetic acid Disinfection byproduct |
3.48 ppb | 0.2 | — | — | — | — | — | 17× over |
| Chloroform Disinfection byproduct |
4.94 ppb | 0.4 | — | — | — | — | — | 12× over |
| Bromoform Disinfection byproduct |
3.45 ppb | 0.5 | — | — | — | — | — | 6.9× over |
| Uranium Radiological |
0.97 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 2.3× over |
| Nitrate Inorganic |
0.139 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Nitrate and nitrite Inorganic |
0.139 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Chromium (hexavalent) Heavy metal |
0.0172 ppb | 0.02 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
74.0 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
4.88 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
69.1 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Selenium Heavy metal |
2.28 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.666 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
2.09 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Vanadium Other |
0.0921 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
2.18 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
1.43 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
1.28 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
1.25 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.601 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
0.444 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.959 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
21.3 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from HIGHLANDS RANCH WSD.